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• Gloves for Gloveboxes, Isolators
• NASA Containment Glovebox; Design and Ergonomics
• Glove Selection for Drybox/Isolation Chambers
• ...

Gloves for Gloveboxes, Isolators

Will the Medical Device manufacturing industry continue to embrace and employ Drybox, Isolator and Mini-environments much like the electronics and pharmaceutical industries have?  Will yield improvements and reduced operating expenses drive the Medical Device Manufacturers to invest in Gloveboxes and Isolators for cost-effective controlled environments?  What effect will this have on the Cleanroom industry?

 Today's manufacturing processes are more frequently being analyzed and reduced to precise time and motion studies to improve quality control and track and contain costs.  Advances in SPC (Statistical Process Control) programs, filtration technologies, air locks, internal microscopes with external monitors, have enabled complete control over temperature, humidity, particulate and process monitoring.  Larger port diameters, new sleeve and glove designs and thinner, more durable polymers have improved ergonomics and tactile sensitivity for glovebox operators. 

 Historical Industries

 Glovebox use began in the 1940's to contain radioactive materials and to protect scientists and researchers experimenting with hazardous materials.  The diameter of the ports were small to limit the potential exposure to users.  The deparment of energy, NASA and many military production and research facilities began using Gloveboxes for handling everything from Plutonium to the first rocks from the moon.   

The electronics industry has embraced Glovebox and Mini-environments for controlling particulate and static contamination. Today's newest 300mm wafer-fabs are incorporating robotic mini-environments to eliminate the largest single source of contamination, the human worker.  Processes that would once be done in a 'cleanroom' environment can now maintain greater environmental controls at lower costs in a glovebox.   Product can be kept up to 1000 times cleaner than more standard cleanrooms.   

The cost differential between controlling a modest sized 1000 square foot class-100 cleanroom with associated garments and supplies versus a Class-10 glovebox is significant.  Perhaps more importantly, the contamination control improvements resulting from keeping the people out of the environment completely should be evident and are certainly documented in various studies.

Preferred gloves for electronics and research applications tend to be butyl for controlling gas permeation and moisture.  Anti-static Nitrile sleeves and gloves have also proven quite popular for seam-sealing microchips and for other static-sensitive devices.  Some cleaning processes require even greater chemical resistance and require the use of Viton gloves.  Neoprene and Hypalon® Accordion Sleeves can be combined with any style hand portion to offer optimal ergonomics and suitability for a myriad of tasks.  

Pharmaceutical manufacturers have been wholeheartedly embracing isolator technologies in recent years.  European and American manufacturers have continued to employ Glovebox (Isolator) technologies for various processes including; Sterility Testing, Sterile processing, liquid filling and bulk powder processing.  Packaging, research and radiological isotope processing are other applications utilizing glovebox technology.  The gloves of choice for many of these applications has been Hypalon® or Nitrile as they have proven to be resistant to sterilants including Vaporized Hydrogen Peroxide.  They are preferred alternatives to the more expensive Viton®.  Layered glove manufacturing processes enables production of more durable and puncture resistant polymers as well as lead-loaded gloves for protection from radioactive materials.

 Health care, food processing, aerospace and education markets also seem to be embracing glovebox technologies further accelerating the growth in this market.  The trend to protect product, people and processes will likely continue this rapid growth, offering benefits of greater control, safer workplaces, improved production yields, improved product shelf-life and a considerable reduction in expenses for operations, consumables and waste disposal costs.

 Drybox gloves are available in various polymers including: Nitrile, Neoprene, Hypalon®, Butyl, and Viton®. New advances in dipping technology have enabled such advanced gloves as Poly-urethane for improved abrasion and chemical resistance and multiple polymer gloves like Poly-urethane/Viton® and Poly-urethane/Hypalon® to offer chemical and puncture/abrasion resistance.

 Design styles range from one-piece fully dipped to two-piece Straight Sleeve or Accordion/Bellows Styles.  The Sleeve/Glove combinations offer GOS (Glove over Sleeve) for sterile applications and GUS (Glove Under Sleeve) for containment.  

 Sleeve/glove combinations also enable wider varieties of sizing and polymer choice and the replacement costs are more economical than replacing fully dipped gloves.  Both styles have options for polymer thickness generally .015' and .030' (15 and 30 mil), but two piece sleeve/glove combinations and advanced manufacturing and processing techniques have brought thinner gloves to the market.  Thicker gauge gloves are used when dexterity and tactile sense are not as critical and when durability and abrasion resistance is a primary concern.

 Gloveboxes and isolators are most frequently constructed of Stainless Steel with Lexan or safety glass windows with entry and egress ports for product as well as glove ports for human access.  There are a wide variety of other materials used in the construction of  these Chambers including: Aluminum, Glass, Sheet metal and Plastic.  It is highly recommended by industry specialists to build mock-up units of wood for consideration of all logistical and ergonomic factors.  Soft-Wall glove boxes are often constructed of PVC or high quality clear plastic and are used in Space or other situations when weight is an extreme concern or when disposability is desired.

 Future Growth

 Glovebox Technology is well suited for adaptation to robotics and some of the manipulator arms on the market are already electronically and mechanically controlled.  The hardware requires custom fittings and covers to protect the moving parts and the products inside these chambers.  Many of these 'mini-environments' are already widely used in the electronics and semi-conductor factories.

 Cost savings realized from glovebox use helps level the international playing field in manufacturing technologies requiring controlled environments.  Companies from countries that may have lesser-developed infrastructures might now be able to research, develop and manufacture products requiring controlled environment processes.  All this, at a fraction of the cost of cleanroom controlled processes.  This trend will ultimately improve quality control and increase yields and profitability industry-wide.  In addition, cost savings can be ultimately passed on to consumers allowing wider access to medical devices and medicines worldwide.

 Cleanrooms require expensive power just to regulate and change the air on a continuous basis.   Supplies including gloves, garments, booties and wipers are also quite costly to purchase and maintain.  Disposal of these items is both environmentally and fiscally expensive.

 Prognosticators envision long assembly lines of  Class 1 (or better) controlled environments functioning perfectly well on a dirt floor with comfortable operators wearing lab coats rather than costly cleanroom 'bunny-suits'.  While this may seem to be an extreme example, it could and should become a reality in the coming years. 

 It seems highly likely that Medical Devices will continue to increase the demand for isolators, dryboxes and mini-environments.  Glovebox/Isolator manufacturers are very busy keeping up with demand and many of their systems are fully validated to comply with regulatory agencies.  Glove supply and offerings are improving rapidly and will continue to meet the custom needs of manual and robotic isolators.  It seems wise for production engineers and managers to consult with drybox and isolator manufacturers before embarking on what could be a far more costly process environment.

 It is hardly likely that Glovebox technology will replace cleanroom manufacturing, especially with some 6000 cleanroom projects completed worldwide since 1999.  It is more likely that Isolators and Gloveboxes will be used in conjunction with Cleanroom technology to further control the variables in critical and/or hazardous manufacturing processes.    

 References & Trademarks:

Hypalon® and Viton® are registered trademarks of DuPont

Cleanrooms Magazine

American Glovebox Society; Guidelines for Gloveboxes

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NASA CONTAINMENT GLOVEBAG; DESIGN AND ERGONOMICS  

PRESENTED TO THE AMERICAN GLOVEBOX SOCIETY (A.G.S.) AGS ANNUAL CONFERENCE; SAN DIEGO, CALIFORNIA August 19, 2005 ; 8:30-10:30 am  "NASA CONTAINMENT GLOVEBAG; DESIGN AND ERGONOMICS"  R.A.RENEHAN RENCO GLOVEHAUS....diptek AGS CONFERENCE; JULY 1996 A.        DRYBOX GLOVES:  EVALUATION AND SELECTION                  I.  SIZES AND STYLES, DIMENSIONS                                  A.  ERGONOMIC CONSIDERATIONS / MOCK-UP OR PROTOTYPE CREATION                                  B.  CUFF DIAMETER / PORT SIZE                                  C.  AMBIDEXTROUS vs. HAND SPECIFIC (LEFT / RIGHT)                                  D.  ACCORDION OR STRAIGHT SLEEVE                  II.  CONFIGURATIONS                                  A.  ONE PIECE FULLY DIPPED                                  B.  ONE PIECE BONDED                                  C.  TWO PIECE, G.O.S.(GLOVE OVER SLEEVE), STERILE APPLICATIONS                                  D.  TWO PIECE, G.U.S.(GLOVE UNDER SLEEVE), POTENT HAZARDOUS                                      APPLICATIONS                                    E.  OTHER                  III.  PHYSICAL PROPERTIES                                  A.  DETERMINING GLOVE'S ELASTOMER \ POLYMER MATERIAL                                                     1.  CHEMICAL RESISTANCE GUIDES AND CHARTS                                                     2.  TEMPERATURE'S EFFECT OF CHEMICAL ON                                                    POLYMERS                                                                        3.  LOW TEMPERATURE'S EFFECT ON FLEXIBILITY OF POLYMERS                                 B.  DETERMINING OF GAUGE \ WEIGHT OF GLOVES                                               1.      COMFORT; TACTILE SENSE / DURABILITY                                               2.      DIPPED, ONE PIECE SOLUTIONS                                                       30 MIL OR 15 MIL OR CUSTOM                                                3.      BONDED GLOVE TO SLEEVE  (NEOPRENE SLEEVE, NEOPRENE                                                        OR LATEX GLOVE)                                                        30 MIL SLEEVE / 15 MIL NEOPRENE HAND OR CUSTOM       c.  OTHER     A.        DRYBOX GLOVES:  EVALUATION AND SELECTION  (CONTINUED)                  IV.  TWO-PIECE COMBINATIONS                                  A.  ACCORDION / BELLOWS STYLE                                                 RUBBER, NEOPRENE, HYPALON, FABRIC                                  B.  STRAIGHT SLEEVES                                                    1.  RUBBER, NEOPRENE, HYPALON, NITRILE, VITON, BUTYL,                                                       EPDM                                                  2.  FABRIC LAMINATES WITH SEAM                                                  3.  PVC CONNECTORS                                                  4.  SILICON, NEOPRENE, HYPALON, VITON O-RING                                                       CONNECTORS                                  C.  HAND PORTIONS                                                  1.  VITON, BUTYL, HYPALON, PVC, NITRILE, RUBBER, E.S.D.                                                        RUBBER, POLYURETHANE, OTHER                                                  2.  AMBIDEXTROUS                                                  3.  HAND SPECIFIC, LEFT RIGHT                  V.  NEW DEVELOPMENTS / REQUIREMENTS                                                    1.  TRI-POLYMER DRY BOX GLOVES                                                                  -  AMBIDEXTROUS                                                                  -  ACRYLIC, NITRILE, BUTADIENE                                                                  -  SIZE 10.5, WHITE, (.030" OR .015”)                                                                  -  RESISTANT TO OXIDIZING CHEMICALS                                                                  -  H2 02 (VHP)    O3                                                                  -  DOES NOT GET TACKY AFTER PROCESSING                                                  2.  AMBI-DEXTEROUS NITRILE GLOVES                                                                  -  CURRENTLY AVAILABLE                                                                  -  8 THOUSANDTHS (.008") (9.75" LONG)                                                                  -  UNDER DEVELOPMENT FOR ABBOTT LABS                                                                  -  WITH BEAD...11.5" LONG                                                  3.  diptek                                                  4.   COMMENTS & CONTRIBUTIONS   B.        NASA CONTAINMENT GLOVEBAG; DESIGN AND ERGONOMICS                 I.   THE CUSTOMER....NASA...LOCKHEED/MARTIN                                  A.  THE NEED....                                       CONTAINMENT GLOVEBAG FOR INTERNATIONAL SPACE STATION                                  B.  RENCO RESPONSE...."HERE IS WHAT WE KNOW....CAN WE HELP?"                II.  CUSTOMER SERVICE....THE PROCESS.....AND THE PHILOSOPHY                                  A.  LISTEN.....LISTEN....LISTEN....SERVICE.....SERVICE....SERVICE                                  B.  ESTABLISH COMPATIBILITY. MATCH SKILLS....COMPLEMENT SKILLS                                  C.  BUILD RELATIONSHIP....BEGIN PROJECT OUTLINE....DETAILED NOTES                                  D.  COMMUNICATIONS RESPONSE                                                 1.  TIMELY  (FAST CALL BACK....QUICK QUOTES...)                                                 2.  EFFICIENT (SUCCINCT...CONCISE....COMPLETE)                                                 3.  VISIONARY (OPEN SYSTEM FOR FUTURE NEEDS)                                                 4.  SENSIBLE, SOLVABLE SOLUTIONS                  III.  RESOURCEFULNESS...USE EXISTING RESOURCES...NO RE-INVENTING                                  A.  ASK FOR ASSISTANCE.....BUILDING PROTOTYPE COULD YOU ASSIST??                                  B.  EXPLAIN THE APPLICATION.....PROJECT FOR INTERNATIONAL SPACE                                       STATION....                                  C.  SHARE INFORMATION.......                                        "THIS IS WHO WE HAVE WORKED WITH....                                        MAYBE THESE FOLKS COULD HELP YOU..." B.        NASA CONTAINMENT GLOVEBAG; DESIGN AND ERGONOMICS (CONTINUED)                 IV.  TECHNICAL SERVICE ASPECTS AND PERFORMANCE                                  A.  THE GLOVE INTERFACE....                                                 1.  RENCO GLOVES ALREADY IN SERVICE ON SHUTTLE AND MIR                                                 2.  COST SAVINGS....EFFICIENCY....NO NEED FOR TESTING FOR                                                      FLIGHT  APPROVAL                                                                                       B.   CONTAINMENT BAG MATERIAL.....T.H.V.  (3M......GLOVE DEVELOPMENT                                          PROJECT)                                                 1.  LISTENED TO THE CUSTOMER'S NEEDS....                                                 2.  OFFERED A SOLUTION....ALTERNATIVE TO TEFLON....                                                 3.   POSITIONED RENCO AS THE VEHICLE TO ADDRESS THEIR                                                       CHALLENGES                                                 4.  OPEN SYSTEM...PUT NASA / 3M IN CONTACT                                                 5.  FACILITATED APPROVAL OF THV FOR FLIGHT HARDWARE                                  C.  DESIGN SPECIFICATIONS PER N.A.S.A. REQUIREMENTS....                                                 1.  STORAGE....                                                 2.  COLLAPSIBILITY, QUICK ASSEMBLY                                                 3.  WEIGHT....                                                 4.  SELF SUPPORTING...                                                 5.  OPTICALLY CORRECT...                                                 6.  40 MICRON SEALABLE...                                                 7.  DESIGN TO MEET THE NEED                                                 8.  VACUUM / UTILITY PORTS                                                 9.  BASE PLATE....                                                 10.  INTAKE FILTER...                                                 11.  VOLUMETRIC SPACE REQUIREMENTS                                                 12.  DIMENSIONS....                                                 13.  ACCESS PORTS                                                 14.  THICKNESS OF MATERIAL                                                 15.  NON-FLAMMABILITY                                                 16.  HUMAN FACTORS                                                 17.  MICRO-GRAVITY                                                 18.  STOWABLE....                                                 19.  NON-GASSING    B.        NASA CONTAINMENT GLOVEBAG; DESIGN AND ERGONOMICS (CONTINUED)                  V.   SEARCHING THE MARKET   (CROSS INDUSTRY INNOVATIONS)                                                 ( OFF SHELF SOLUTIONS )                                                 "OPEN MARKET .... OPEN MIND"                                 A.  RELATED PRODUCTS                                                 1.   TOY COMPANIES...                                                 2.   CAMERA FILM CHANGING TENTS....                                                 3.   TENT COMPANIES                                                 4.   SAIL MAKERS                                                 5.   ZIPPER COMPANIES                                                 6.   HYDRAULIC SHOPS                                                 7.   AWNINGS                                                 8.   ALUMINUM EXTRUDERS                                                 9.   STITCHERS                                                 10.  PLASTIC EXTRUDERS...SCYTHERS....                                                 11.  LANDFILL LINERS                                                 12.  D.O.E. CALLS....ROCKYFLATS....RMRS                                                 13.  GLOVE BAG FABRICATORS                                  B.  ATTENTIVENESS TO EVERYDAY PRODUCTS & PEOPLE                                                 1.  BEING ALERT TO NEW APPLICATIONS                                                 2.  OPENING MIND TO NEW SOURCES                                                 3.  DISCOVERING CROSS-INDUSTRY INNOVATION                                           ( UTILITY TENTS, CAMPING, HYDRAULICS, PLASTICS)                                   C.  INVESTIGATION, "WILLINGNESS TO GO THE EXTRA MILE" SIGHT VISITS                                  D.  OPENNESS, TRUST, FAITH                                  E.  PERFORMANCE, DELIVERY, BEST EFFORT                                  F.  POSITIVE ATTITUDE, CONTINUOUS LEARNING, CO-OPERATION                  VI.  TIMETABLE, TARGETS, AND DEADLINES                                 A.  REALISTIC GOALS....                                 B.  COMMUNICATION WITH VENDORS...SPECIFIC DATES                                 C.  CONTINGENCY PLANS....COVER YOUR BUTT                                 D.  COMMUNICATE DELAYS QUICKLY TO CUSTOMER                  VII.  SPARE NO EXPENSE                                 A.  GET THE JOB DONE                                 B.  MAKE IT HAPPEN                                 C.  "PROTOTYPING IS A COSTLY YET WORTHWHILE LEARNING                                      EXPERIENCE...SERVICE THE CUSTOMER AND REWARDS SHOULD                                      FOLLOW."                                                                                                                                                  RICHARD A. RENEHAN, PRESIDENT                                                                                                                                                           RENCO CORPORATION Back to Top Glove Selection for Drybox/Isolation Chambers   A.   PORT DESIGNS AND SIZES                  I.   OVAL vs. ROUND                                 A.   VERTICAL, HORIZONTAL, ANGLED OVALS                                 B.   SIZES 5", 6", 7", 8", 10", 12" DIAMETERS (METRIC & CIRCUMFERENCE                  II.   MATERIALS AND MOUNTS (INTERNAL V. EXTERNAL)  B.   GLOVE SELECTION                  I.   ONE PIECE FULL LENGTH                                   A.   AVAILABLE MATERIALS                                 B.    FEATURES & BENEFITS                                 C.    COMPROMISES & DRAWBACKS                                 D.   COMMON APPLICATIONS                  II.   SLEEVE/GLOVE COMBINATION (REPLACEABLE HAND VERSIONS)                                 A.   AVAILABLE MATERIALS                                 B.    FEATURES & BENEFITS                                 C.    DRAWBACKS                                 D.    COMMON APPLICATIONS                  III.   ACCORDION / BELLOWS STYLE                                 A.   MATERIALS                                 B.    FEATURES & BENEFITS                                 C.    DRAWBACKS                                 D.    COMMON APPLICATIONS                 C.   STERILE APPLICATIONS                 I.   VHP COMPATIBLE MATERIALS                 II.   HEAT STERILIZATION                 III.   PROPER GLOVE SELECTION  D.   OTHER CONCEPTS AND CONCERNS FOR DISCUSSION                  I.    CONTAINMENT APPLICATIONS                 II.   PORT/GLOVE CHANGING SYSTEMS                 III.   AMBIDEXTROUS V. HAND SPECIFIC                 IV.   COST CONTAINMENT                 V.   NEW MATERIALS AND DESIGNS                 VI.   HAZARDOUS MATERIALS / WASTES  PRESENTED TO THE AMERICAN GLOVEBOX SOCIETY BY R.A. RENEHAN, RENCO CORPORATION;(800) 257.8284   Glove Selection for Drybox/Isolation Chambers PRESENTED TO THE AMERICAN GLOVEBOX SOCIETY 7/20/95 RICH RENEHAN RENCO GLOVEHAUS (800) 257.8284  Gloves have been a part of my life since my doctor delivered me over thirty years ago.  They are more or less a part of the family jewels.  The Renco name is derived from William Renehan, the founder and patent holder for the replaceable hand drybox glove and the accordion/bellows style sleeves.  I can remember as a seven year old kid, playing floor hockey with rings and springs behind Peggy's sandwich shop while my dad and his workers assembled gloves.   I also remember demonstrating static dissipative finger cots (pilfered from my father's office) at a BC football game and getting a big laugh from all Bill's friends.  I never expected to follow his hand prints, in fact he always encouraged me to sell something I love and enjoy.  Well, having sold ice cream, cookware, boot repair kits, computers, bicycles and gloves, I realized that it is not that important what we sell.  The important thing is to do our best with what we are given and to serve the people in the kindest possible fashion.  This attitude has allowed me to greatly enjoy the glove business and has allowed Renco to serve customers from IBM to NASA, Fisher Scientific to Merck as well as many glovebox O.E.M. customers.   The honor I feel for having the opportunity to present Renco's views to this select group of engineers and scientists is only outweighed by the honor and respect for my father's commitment to his family, associates, and for his contributions to glovebox technology.  Although retired now, he would still love to offer the glovebox industry, (quote) " a stainless steel glove with surgical dexterity."  Selecting the proper gloves for isolation chamber applications requires a careful analysis of processes and functionality with respect to user protection, ergonomics, product protection and production objectives.  The selection of the proper "user-friendly" interface for the end-user is as critically important as particle filtration, barrier materials, fixture selection, monitoring pressure, leak testing, entrance and egress etc.  As you all well know each of these considerations need equal consideration with respect to the process as a whole.   Prior to construction of the chamber, the primary criteria for selecting the proper glove is the amount of "reach" required and the direction and frequency of user movement inside the glovebox.  This may require a model or a mock replica of the proposed design to determine the relationships between the equipment and the manufacturing process points to verify the functionality of the user/worker interaction.1      PORT SELECTION, SIZE AND ALIGNMENT  A full scale model may be required to effectively design and test the optimal ergonomic positioning and sizing of the ports.  The human factor is probably the most critical option in designing anything.  Making an object functional, easy and comfortable to use greatly enhances the operators perception and ultimately their performance. Port size and alignment must include a consideration of the following:             a.         Level of workspace (process) platform in relation to the height of the users.             b.         Depth of the box with respect to the reach required for tool and control access.             c.         Direction of process flow (vertical; horizontal; combination).             d.         Whether operator needs occasional "full arm/shoulder" reach.  Consideration of these and application specific factors can help us determine the optimum diameter or circumference of the ports.  Some common parameters have previously been defined by the glovebox industry.  The height of the center-point of the ports will usually determine the height of the workspace platform.  Attention must be given to the variety of operators, standing or sitting operations and the viewing area required.  Industry experience has proven a 48" height to port center and an 18" viewing area as effective.  The specific application will determine the size of the port and the alignment.  Common industry diameters for drybox gloves evolved from the use of chambers for handling radioactive materials.  The concept was to use smaller port diameters to limit the potential exposure of the operators.  This resulted in diameters of 5", 6", 7" and 8" ports.  The most common port size having an eight inch diameter or a 25.13" (638.3mm) circumference.  The vast majority of gloves and sleeve/glove combinations are designed for 8" circular ports.   Engineers and innovators soon realized that larger port sizes were required for certain applications requiring maximum reach and interchangeable workers.  Ports and sleeves were thus designed for 10" and 12" diameter and anywhere in between or above.  Gloves and sleeves of straight and bellows styles were created of 10" and 12" diameter ports improving the workers access and comfort, but decreasing the viewing area. Ergonomics has been an emerging science of the 1980's and 1990's.  Attention to operator comfort and safety has enhanced performance in many cases, has protected workers from repetitive motion stress and has created new products in a new industry dedicated to healthy people.   Another adaptation of glove ports with ergonomic and process flow considerations was designing oval ports and aligning them either horizontally, vertically or at an angle.  The circumference of the oval port should correspond to the circumference of a circular port of a specific diameter (e.g. Oval port with a 25.13 circumference will fit gloves designed for an 8" diameter circular port.)( see handout)  This will ensure a tight fit of the glove to the oval port.  Oval ports can allow improved reach and do not necessarily need to be symmetrical or at the same angle.  Ergonomics means operator comfort and functionality, not aesthetic beauty and balance.    GLOVE MATERIAL SELECTION  During the production process considerations to determine the ideal port size and alignment, attention must be given to glove polymer selection, as this will affect port dimension decisions as well as glove thickness (gauge) and characteristics.   Some common questions for glove selection are:  1.         Will the process involve potent hazardous materials, radioactive agents or sterilized products?  2.         How will the gloves perform with process materials? 3.         Will the glovebox be under positive pressure or negative pressure?  4.         What is the atmosphere best suited for the application?  5.         What level of dexterity is required?  6.         Hand Specific or ambidextrous gloves? 7.         Is Electro Static Discharge (ESD) at issue?  8.         What level of cleanliness is required? 9.         Is there a sterilization cycle? 10.       How frequently must the gloves be changed?  The selection of the proper glove material will be heavily influenced by user safety, product potency, cost, sense of touch, variety of users and comfort.  An important place to start is Material Safety Data Sheet or MSDS.  This document can help engineers determine the level of risk to humans and the proper handling techniques for the materials in question.  Cross referencing the active and inert ingredients and process materials with glove polymer/chemical compatibility charts, glovebox designers can have an initial idea of available glove options.   Further testing with the possible glove materials and the products being handled should be done "in house" to determine the glove's ultimate suitability for the applications in question.  Many of the standard tests outlined in the ASTM (American Society for Tests and Measures) can be used for certain tests or as guidelines for testing application-specific materials with the polymers of choice.    NATURAL RUBBER LATEX                                                                     (Polyisoprene) Natural Rubber offers the technician a softness unavailable with other synthetic polymers.  Resists most moderate chemicals, wet or dry, organic acids, alcohols, ketones, aldehydes.  Attacked by ozone, strong acids, fats, oils, greases, most hydrocarbons. Tensile strength:  about 4000psi:   NEOPRENE  (Chloroprene)                                                                           (Chloroprene polymer, Butadiene) General purpose elastomer.  Resists moderate chemicals and acids, ozone, oils, fats, greases, many oils and solvents.  Attacked by strong oxidizing acids, esters, ketones, chlorinated aromatic and nitro hydrocarbons. Tensile strength:  about 3000psi   NITRILE                                                                                            (Butadiene, Acrylonitrile Copolymer) Great solvent resistance.  Very durable with excellent puncture resistance.  Resists many hydrocarbons, fats, oils, greases, hydraulic fluids, chemicals.  Attacked by ozone, ketones, esters, aldehydes, chlorinated and nitro hydrocarbons. Tensile strength:  about 6000psi   HYPALON                                                                                         (Chlorosulfonated Polyethylene) Good ozone, heat, soil and abrasion resistance.  Good resistance to oxidizing chemicals.  State of the industry for VHP sterilization.  Similar resistance to neoprene with improved acid resistance.  Attacked by concentrated oxidizing acids, esters, ketones, chlorinated aromatic and nitro hydrocarbons. Tensile strength:  about 6000psi  BUTYL                                                                                               (Isobutlene, Isoprene) Very good gas permeation resistance, ozone and heat resistance.  Degraded by aromatic hydrocarbons. Best barrier to water vapor, gases and certain toxic chemicals.  Flexible even at low temperatures.  Resists animal and vegetable fats, oils, greases, ozone, strong oxidizing chemicals.  Attacked by Petroleum solvents, coal tar solvents, aromatic hydrocarbons.  EPDM (TERPOLYMER)                                                                   (Ethylene Propylene) Soft with ozone and oil resistance.  Resists animal and vegetable oils, ozone, strong oxidizing chemicals.  Attacked by mineral oils and solvents, aromatic hydrocarbons.  VITON, FLUOREL  (FLUOROELASTOMER)                    (Vinylidene fluoride, Chlorotrifluoroethylene) Acid, Solvent and heat resistant.  Degraded by ketone solvents. Resists all aliphatic, aromatic and halogenated hydrocarbons, acids, animal and vegetable oils.  Attacked by ketones, low mole weight esters and nitro containing compounds.  Certain models of gloves are lead-loaded for radiation shielding.  Other models have combined properties such as the Hypalon coated Neoprene gloves.  Dual thickness neoprene offers superior touch sensitivity.  Also available:  low sulfur neoprene, latex, blue divetex, nitrile and PVC. Hypalon and Viton are registered trademarks of EI DuPont. Flourel is a registered trademark of 3M.   ONE-PIECE FULLY DIPPED DRYBOX GLOVES  Drybox glove materials are generally available in two gauges, 15mil (.015") and 30mil (.030").  This allows for a certain amount of flexibility when determining the protection requirements for handling materials and the level of dexterity required.   With potent applications where gross motor skills are used, a thirty mil glove will offer the most protection and the longest life.  When fine motor skills are required and the potency of the materials is less hazardous, a "lighter" gauge glove can be used.  Sizing on the one piece, fully dipped gloves are industrial sized at 8.5, 9.75, and 10.5.  Ambidextrous and hand specific styles are available in most of the fully dipped polymers.  One piece glove solutions are ideal for potent situations requiring total containment.  Since glovebox gloves evolved from potent containment situations, industry standard, one-piece solutions continue to be popular in many applications.  One-piece solutions also provide the only solution which offers complete single-polymer protection when the application requires equal protection for the sleeve and the hand portion.   REPLACEABLE HAND DRYBOX GLOVE COMBINATIONS  Certain applications which called for thinner gloves or gloves of unique polymer or size requirements have driven the replaceable hand drybox glove market.  Cost benefits are realized when comparing the cost of replacing a one-piece, fully-dipped pair of gloves to the cost of replacing a 12" or 14" hand portion only (HPO).  The hand portion is the component of the manual access system which is most frequently exposed to the product and processes.  This factor leads to faster wear and tear on the glove and initially created the need for a two piece solution.  Also driving the two piece configuration was user comfort and cost factors.  Today, the air-tight, liquid tight changeable hand drybox gloves have offered glovebox users flexibility in glove selection whereby high-end glove materials can be combined with less critical sleeve materials to offer equal protection with added flexibility.  While this solution is not applicable to all situations, it certainly should be considered.  New developments in the aseptic replacement of the hand portion have made the two piece solution an even more economical alternative.  While the Glove-Under-Sleeve (GUS) aluminum ring and stainless spring connectors developed over thirty years ago are still popular today, certain glovebox OEM's have employed plastic wrist connectors with neoprene o-rings.  Potent applications with negative pressure conditions may require the glove to be discarded through the chamber.  Under these conditions, two-piece glove users are often better suited with a Glove Under Sleeve (GUS) solution where the contaminated glove can be pushed through the wrist connector into the chamber for proper disposal.  Somewhat more costly, the Glove Over Sleeve (GOS) connection is suited for aseptic and sterile glove changes where the glove must be pulled through the sleeve to the outside without breaking containment.   ACCORDION/BELLOWS STYLE SLEEVES  The accordion bellows sleeve/glove combination has proved useful to the containment industry for over 30 years.  It was originally designed for several reasons including:             a.         prevention of "blow-back" in positive pressure environments.             b.         ergonomic design holds sleeve off of the operators arms             c.         air-flow inside sleeve contributes to comfort factor             d.         heavy gauge (50 mil) protects user  The bellows style is available in a one-piece bonded glove/sleeve combination or is available in the classic replaceable hand drybox glove.  The one piece is better suited for potent hazardous materials handling while the replaceable hand style offers the economic savings of changing the glove while keeping the sleeve.  Accordion sleeves also allow for a more complete cleansing or sterilization cycle by eliminating folds and creases and allowing even flow run-off.  The standard 8" diameter port size has been adapted to fit 6", 10" and 12" port sizes and like all drybox gloves, it can stretch to fit an oval port of equal circumference.      STORAGE  All elastomers degrade over time  The aging characteristics of specific polymers is determined by the chemical structure of the polymer and by anti-degrading additives.  Gloves should be stored in their original shipping box in a dry place.  Sixty to Eighty degrees is an optimum storage temperature range.  Folds or creases can accelerate the aging and compromise the integrity of the sleeve.   Ultra violate light and ozone tend to accelerate the degradation of elastomers.  Low temperatures stiffen elastomers and can contribute to cracking.  High temperatures accelerate aging which also results in loss of physical strength.     TESTING AND EVALUATING  Glovebox gloves require testing before selection as well as prior to use.  As mentioned earlier, polymers age differently under certain circumstances.  It is wise to test the gloves or sleeve/glove combination prior to use in order to assure user safety and product protection.  After examining the criteria of port alignment, the compatibility of gloves with processes, and the style of glove to be used, it is suggested that the engineer conduct "in house" tests on the glove material.  Many of the ASTM standards can be employed to test the materials for the following:               1.         Resistance to corrosive atmospheres and environments             2.         Radiation degradation             3.         Tear strength             4.         Puncture resistance             5.         Radiation shielding             6.         Manual dexterity  Prior to use, the technician also needs to test the product for integrity.  A visual check and a leakage test by filling the product with air is sufficient at this stage.  If all checks out the glove is installed and the cycle begins.   Leak testing is done at the factory level by using electrodes placed in water and charging to 5000 volts and 10,000 volts for 15mil and 30mil gloves respectively.  If the electricity passes through, the gloves will fail.  There are so many layers on these gloves that leakage is hardly a factor and the visual inspection will determine where possible problems may arise.   After installation, a pressure check is done on the chamber with a helium test to verify the seals.  This is typically done with 90% helium and the mass spectrometer is set at 10-6 cc/min.   Sometimes Argon is used for certain welding applications.  Some other glovebox manufacturers will snoop or a soap bubble test to isolate the leakage.  At any rate, it is important to isolate the leak and rectify the situation with the proper replacement gloves and to determine at what level the defect is occurring (production, Q.C., storage, handling, installation).  Special thanks for assisting with this paper go to the following individuals:  Mr. William J. Renehan Mr. William G. Renehan Mr. Fred Sebode Mr. Steve Chunglo Mr. Russ Kraniak Mr. Rodney Smith   REFERENCES  1.  Rahe, Hank; "Barrier Isolation Technology Laboratory to Production"; Cleanrooms '95 East Proceedings; April 1995.  ASTM STANDARDS  C852-93          DESIGN CRITERIA FOR PLUTONIUM GLOVEBOXES D2000-90        STANDARD CLASSIFICATION FOR RUBBER PRODUCTS IN AUTO                                                   APPLICATIONS D395               TEST FOR RUBBER PROPERTIES (COMPRESSION SET) D412               TEST FOR THERMO PLASTIC RUBBER AND ELASTOMERS (TENSION) D1777             THICKNESS OF TEXTILES E1003              HYDRA STATIC LEAK TESTING (pressure; leak detection) E515                BUBBLE EMISSION TEST (Leak detection) E1002              ULTRA SONIC TECHNIQUES (LEAK DETECTION) ES21                BLOOD BORNE PATHOGENS ES22                BLOOD BORNE PATHOGENS F 903               RESISTANCE OF CLOTHING TO PERMEATION BY LIQUIDS  CFR METHODS 606, 809, 820 TITLE 21 PARTS. 58, 210, 211, 212   Note:  The previous pages are offered as a general guide and indication of the suitability of various elastomers in use today with certain materials.  The resistance and degradation notes are based on published literature of various polymer suppliers and rubber manufacturers but in some cases, they are the opinion of experienced compounders.  Thus, there is no guarantee of their accuracy and we assume no responsibility for  the use thereof.  Several factors also influence the performance of the polymers in this report.  It is important to consider the temperature of service, the conditions of service, the grade of the polymer and the compound itself.  In light of the above factors, it is best to test all materials for your specific applications.  RAR Back to Top Back to Top

Renco Corporation 5 Beaver Dam Road, PO Box 412, Manchester, MA 01944 USA Phone: 800.257.8284 ~ Fax: 978.526.8015 ~ E-mail: renco@rencogloves.com

AGS ANNUAL CONFERENCE; SAN DIEGO, CALIFORNIA

August 19, 2005 ; 8:30-10:30 am

 "NASA CONTAINMENT GLOVEBAG; DESIGN AND ERGONOMICS"

 R.A.RENEHAN

RENCO GLOVEHAUS....diptek

AGS CONFERENCE; JULY 1996

A.        DRYBOX GLOVES:  EVALUATION AND SELECTION

                 I.  SIZES AND STYLES, DIMENSIONS

                                 A.  ERGONOMIC CONSIDERATIONS / MOCK-UP OR PROTOTYPE CREATION

                                 B.  CUFF DIAMETER / PORT SIZE

                                 C.  AMBIDEXTROUS vs. HAND SPECIFIC (LEFT / RIGHT)

                                 D.  ACCORDION OR STRAIGHT SLEEVE

                 II.  CONFIGURATIONS

                                 A.  ONE PIECE FULLY DIPPED

                                 B.  ONE PIECE BONDED

                                 C.  TWO PIECE, G.O.S.(GLOVE OVER SLEEVE), STERILE APPLICATIONS

                                 D.  TWO PIECE, G.U.S.(GLOVE UNDER SLEEVE), POTENT HAZARDOUS                                      APPLICATIONS  

                                 E.  OTHER

                 III.  PHYSICAL PROPERTIES

                                 A.  DETERMINING GLOVE'S ELASTOMER \ POLYMER MATERIAL

                                                    1.  CHEMICAL RESISTANCE GUIDES AND CHARTS

                                                    2.  TEMPERATURE'S EFFECT OF CHEMICAL ON                                                    POLYMERS                   

                                                    3.  LOW TEMPERATURE'S EFFECT ON FLEXIBILITY OF POLYMERS

                                B.  DETERMINING OF GAUGE \ WEIGHT OF GLOVES

                                              1.      COMFORT; TACTILE SENSE / DURABILITY

                                              2.      DIPPED, ONE PIECE SOLUTIONS

                                                      30 MIL OR 15 MIL OR CUSTOM 

                                              3.      BONDED GLOVE TO SLEEVE  (NEOPRENE SLEEVE, NEOPRENE                                                        OR LATEX GLOVE)

                                                       30 MIL SLEEVE / 15 MIL NEOPRENE HAND OR CUSTOM

      c.  OTHER  

 

A.        DRYBOX GLOVES:  EVALUATION AND SELECTION  (CONTINUED)

                 IV.  TWO-PIECE COMBINATIONS

                                 A.  ACCORDION / BELLOWS STYLE

                                                RUBBER, NEOPRENE, HYPALON, FABRIC

                                 B.  STRAIGHT SLEEVES

 

                                                 1.  RUBBER, NEOPRENE, HYPALON, NITRILE, VITON, BUTYL,                                                       EPDM

                                                 2.  FABRIC LAMINATES WITH SEAM

                                                 3.  PVC CONNECTORS

                                                 4.  SILICON, NEOPRENE, HYPALON, VITON O-RING

                                                      CONNECTORS

                                 C.  HAND PORTIONS

                                                 1.  VITON, BUTYL, HYPALON, PVC, NITRILE, RUBBER, E.S.D.                                                        RUBBER, POLYURETHANE, OTHER

                                                 2.  AMBIDEXTROUS

                                                 3.  HAND SPECIFIC, LEFT RIGHT

                 V.  NEW DEVELOPMENTS / REQUIREMENTS

 

                                                 1.  TRI-POLYMER DRY BOX GLOVES

                                                                 -  AMBIDEXTROUS

                                                                 -  ACRYLIC, NITRILE, BUTADIENE

                                                                 -  SIZE 10.5, WHITE, (.030" OR .015”)

                                                                 -  RESISTANT TO OXIDIZING CHEMICALS

                                                                 -  H2 02 (VHP)    O3

                                                                 -  DOES NOT GET TACKY AFTER PROCESSING

                                                 2.  AMBI-DEXTEROUS NITRILE GLOVES

                                                                 -  CURRENTLY AVAILABLE

                                                                 -  8 THOUSANDTHS (.008") (9.75" LONG)

                                                                 -  UNDER DEVELOPMENT FOR ABBOTT LABS

                                                                 -  WITH BEAD...11.5" LONG

                                                 3.  diptek

                                                 4.   COMMENTS & CONTRIBUTIONS

  B.        NASA CONTAINMENT GLOVEBAG; DESIGN AND ERGONOMICS

                I.   THE CUSTOMER....NASA...LOCKHEED/MARTIN

                                 A.  THE NEED....

                                      CONTAINMENT GLOVEBAG FOR INTERNATIONAL SPACE STATION

                                 B.  RENCO RESPONSE...."HERE IS WHAT WE KNOW....CAN WE HELP?"

               II.  CUSTOMER SERVICE....THE PROCESS.....AND THE PHILOSOPHY

                                 A.  LISTEN.....LISTEN....LISTEN....SERVICE.....SERVICE....SERVICE

                                 B.  ESTABLISH COMPATIBILITY. MATCH SKILLS....COMPLEMENT SKILLS

                                 C.  BUILD RELATIONSHIP....BEGIN PROJECT OUTLINE....DETAILED NOTES

                                 D.  COMMUNICATIONS RESPONSE

                                                1.  TIMELY  (FAST CALL BACK....QUICK QUOTES...)

                                                2.  EFFICIENT (SUCCINCT...CONCISE....COMPLETE)

                                                3.  VISIONARY (OPEN SYSTEM FOR FUTURE NEEDS)

                                                4.  SENSIBLE, SOLVABLE SOLUTIONS

                 III.  RESOURCEFULNESS...USE EXISTING RESOURCES...NO RE-INVENTING

                                 A.  ASK FOR ASSISTANCE.....BUILDING PROTOTYPE COULD YOU ASSIST??

                                 B.  EXPLAIN THE APPLICATION.....PROJECT FOR INTERNATIONAL SPACE                                       STATION....

                                 C.  SHARE INFORMATION.......

                                       "THIS IS WHO WE HAVE WORKED WITH....

                                       MAYBE THESE FOLKS COULD HELP YOU..."

B.        NASA CONTAINMENT GLOVEBAG; DESIGN AND ERGONOMICS (CONTINUED)

                IV.  TECHNICAL SERVICE ASPECTS AND PERFORMANCE

                                 A.  THE GLOVE INTERFACE....

                                                1.  RENCO GLOVES ALREADY IN SERVICE ON SHUTTLE AND MIR

                                                2.  COST SAVINGS....EFFICIENCY....NO NEED FOR TESTING FOR                                                      FLIGHT  APPROVAL

                                                    

                                 B.   CONTAINMENT BAG MATERIAL.....T.H.V.  (3M......GLOVE DEVELOPMENT                                          PROJECT)

                                                1.  LISTENED TO THE CUSTOMER'S NEEDS....

                                                2.  OFFERED A SOLUTION....ALTERNATIVE TO TEFLON....

                                                3.   POSITIONED RENCO AS THE VEHICLE TO ADDRESS THEIR                                                       CHALLENGES

                                                4.  OPEN SYSTEM...PUT NASA / 3M IN CONTACT

                                                5.  FACILITATED APPROVAL OF THV FOR FLIGHT HARDWARE

                                 C.  DESIGN SPECIFICATIONS PER N.A.S.A. REQUIREMENTS....

                                                1.  STORAGE....

                                                2.  COLLAPSIBILITY, QUICK ASSEMBLY

                                                3.  WEIGHT....

                                                4.  SELF SUPPORTING...

                                                5.  OPTICALLY CORRECT...

                                                6.  40 MICRON SEALABLE...

                                                7.  DESIGN TO MEET THE NEED

                                                8.  VACUUM / UTILITY PORTS

                                                9.  BASE PLATE....

                                                10.  INTAKE FILTER...

                                                11.  VOLUMETRIC SPACE REQUIREMENTS

                                                12.  DIMENSIONS....

                                                13.  ACCESS PORTS

                                                14.  THICKNESS OF MATERIAL

                                                15.  NON-FLAMMABILITY

                                                16.  HUMAN FACTORS

                                                17.  MICRO-GRAVITY

                                                18.  STOWABLE....

                                                19.  NON-GASSING

   B.        NASA CONTAINMENT GLOVEBAG; DESIGN AND ERGONOMICS (CONTINUED)

                 V.   SEARCHING THE MARKET   (CROSS INDUSTRY INNOVATIONS)

                                                ( OFF SHELF SOLUTIONS )

                                                "OPEN MARKET .... OPEN MIND"

                                A.  RELATED PRODUCTS

                                                1.   TOY COMPANIES...

                                                2.   CAMERA FILM CHANGING TENTS....

                                                3.   TENT COMPANIES

                                                4.   SAIL MAKERS

                                                5.   ZIPPER COMPANIES

                                                6.   HYDRAULIC SHOPS

                                                7.   AWNINGS

                                                8.   ALUMINUM EXTRUDERS

                                                9.   STITCHERS

                                                10.  PLASTIC EXTRUDERS...SCYTHERS....

                                                11.  LANDFILL LINERS

                                                12.  D.O.E. CALLS....ROCKYFLATS....RMRS

                                                13.  GLOVE BAG FABRICATORS

                                 B.  ATTENTIVENESS TO EVERYDAY PRODUCTS & PEOPLE

                                                1.  BEING ALERT TO NEW APPLICATIONS

                                                2.  OPENING MIND TO NEW SOURCES

                                                3.  DISCOVERING CROSS-INDUSTRY INNOVATION                                           ( UTILITY TENTS, CAMPING, HYDRAULICS, PLASTICS) 

                                 C.  INVESTIGATION, "WILLINGNESS TO GO THE EXTRA MILE" SIGHT VISITS

                                 D.  OPENNESS, TRUST, FAITH

                                 E.  PERFORMANCE, DELIVERY, BEST EFFORT

                                 F.  POSITIVE ATTITUDE, CONTINUOUS LEARNING, CO-OPERATION

                 VI.  TIMETABLE, TARGETS, AND DEADLINES

                                A.  REALISTIC GOALS....

                                B.  COMMUNICATION WITH VENDORS...SPECIFIC DATES

                                C.  CONTINGENCY PLANS....COVER YOUR BUTT

                                D.  COMMUNICATE DELAYS QUICKLY TO CUSTOMER

                 VII.  SPARE NO EXPENSE

                                A.  GET THE JOB DONE

                                B.  MAKE IT HAPPEN

                                C.  "PROTOTYPING IS A COSTLY YET WORTHWHILE LEARNING                                      EXPERIENCE...SERVICE THE CUSTOMER AND REWARDS SHOULD                                      FOLLOW."

                                                                                                                                                 RICHARD A. RENEHAN, PRESIDENT                                                                                                                                                           RENCO CORPORATION

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Glove Selection for Drybox/Isolation Chambers

 

A.   PORT DESIGNS AND SIZES

                 I.   OVAL vs. ROUND

                                A.   VERTICAL, HORIZONTAL, ANGLED OVALS

                                B.   SIZES 5", 6", 7", 8", 10", 12" DIAMETERS (METRIC & CIRCUMFERENCE

                 II.   MATERIALS AND MOUNTS (INTERNAL V. EXTERNAL)

 B.   GLOVE SELECTION

                 I.   ONE PIECE FULL LENGTH  

                                A.   AVAILABLE MATERIALS

                                B.    FEATURES & BENEFITS

                                C.    COMPROMISES & DRAWBACKS

                                D.   COMMON APPLICATIONS

                 II.   SLEEVE/GLOVE COMBINATION (REPLACEABLE HAND VERSIONS)

                                A.   AVAILABLE MATERIALS

                                B.    FEATURES & BENEFITS

                                C.    DRAWBACKS

                                D.    COMMON APPLICATIONS

                 III.   ACCORDION / BELLOWS STYLE

                                A.   MATERIALS

                                B.    FEATURES & BENEFITS

                                C.    DRAWBACKS

                                D.    COMMON APPLICATIONS

                C.   STERILE APPLICATIONS

                I.   VHP COMPATIBLE MATERIALS

                II.   HEAT STERILIZATION

                III.   PROPER GLOVE SELECTION

 D.   OTHER CONCEPTS AND CONCERNS FOR DISCUSSION

                 I.    CONTAINMENT APPLICATIONS

                II.   PORT/GLOVE CHANGING SYSTEMS

                III.   AMBIDEXTROUS V. HAND SPECIFIC

                IV.   COST CONTAINMENT

                V.   NEW MATERIALS AND DESIGNS

                VI.   HAZARDOUS MATERIALS / WASTES

 PRESENTED TO THE AMERICAN GLOVEBOX SOCIETY

BY R.A. RENEHAN, RENCO CORPORATION;(800) 257.8284

 

Glove Selection for Drybox/Isolation Chambers

PRESENTED TO THE AMERICAN GLOVEBOX SOCIETY 7/20/95

RICH RENEHAN

RENCO GLOVEHAUS

(800) 257.8284

 Gloves have been a part of my life since my doctor delivered me over thirty years ago.  They are more or less a part of the family jewels.  The Renco name is derived from William Renehan, the founder and patent holder for the replaceable hand drybox glove and the accordion/bellows style sleeves.  I can remember as a seven year old kid, playing floor hockey with rings and springs behind Peggy's sandwich shop while my dad and his workers assembled gloves. 

 I also remember demonstrating static dissipative finger cots (pilfered from my father's office) at a BC football game and getting a big laugh from all Bill's friends.  I never expected to follow his hand prints, in fact he always encouraged me to sell something I love and enjoy.  Well, having sold ice cream, cookware, boot repair kits, computers, bicycles and gloves, I realized that it is not that important what we sell.  The important thing is to do our best with what we are given and to serve the people in the kindest possible fashion.  This attitude has allowed me to greatly enjoy the glove business and has allowed Renco to serve customers from IBM to NASA, Fisher Scientific to Merck as well as many glovebox O.E.M. customers. 

 The honor I feel for having the opportunity to present Renco's views to this select group of engineers and scientists is only outweighed by the honor and respect for my father's commitment to his family, associates, and for his contributions to glovebox technology.  Although retired now, he would still love to offer the glovebox industry, (quote) " a stainless steel glove with surgical dexterity."

 Selecting the proper gloves for isolation chamber applications requires a careful analysis of processes and functionality with respect to user protection, ergonomics, product protection and production objectives.  The selection of the proper "user-friendly" interface for the end-user is as critically important as particle filtration, barrier materials, fixture selection, monitoring pressure, leak testing, entrance and egress etc.  As you all well know each of these considerations need equal consideration with respect to the process as a whole. 

 Prior to construction of the chamber, the primary criteria for selecting the proper glove is the amount of "reach" required and the direction and frequency of user movement inside the glovebox.  This may require a model or a mock replica of the proposed design to determine the relationships between the equipment and the manufacturing process points to verify the functionality of the user/worker interaction.1 

   

PORT SELECTION, SIZE AND ALIGNMENT

 A full scale model may be required to effectively design and test the optimal ergonomic positioning and sizing of the ports.  The human factor is probably the most critical option in designing anything.  Making an object functional, easy and comfortable to use greatly enhances the operators perception and ultimately their performance.

Port size and alignment must include a consideration of the following:

            a.         Level of workspace (process) platform in relation to the height of the users.

            b.         Depth of the box with respect to the reach required for tool and control access.

            c.         Direction of process flow (vertical; horizontal; combination).

            d.         Whether operator needs occasional "full arm/shoulder" reach.

 Consideration of these and application specific factors can help us determine the optimum diameter or circumference of the ports.  Some common parameters have previously been defined by the glovebox industry.  The height of the center-point of the ports will usually determine the height of the workspace platform.  Attention must be given to the variety of operators, standing or sitting operations and the viewing area required.  Industry experience has proven a 48" height to port center and an 18" viewing area as effective.

 The specific application will determine the size of the port and the alignment.  Common industry diameters for drybox gloves evolved from the use of chambers for handling radioactive materials.  The concept was to use smaller port diameters to limit the potential exposure of the operators.  This resulted in diameters of 5", 6", 7" and 8" ports.  The most common port size having an eight inch diameter or a 25.13" (638.3mm) circumference.  The vast majority of gloves and sleeve/glove combinations are designed for 8" circular ports. 

 Engineers and innovators soon realized that larger port sizes were required for certain applications requiring maximum reach and interchangeable workers.  Ports and sleeves were thus designed for 10" and 12" diameter and anywhere in between or above.  Gloves and sleeves of straight and bellows styles were created of 10" and 12" diameter ports improving the workers access and comfort, but decreasing the viewing area.

Ergonomics has been an emerging science of the 1980's and 1990's.  Attention to operator comfort and safety has enhanced performance in many cases, has protected workers from repetitive motion stress and has created new products in a new industry dedicated to healthy people. 

 Another adaptation of glove ports with ergonomic and process flow considerations was designing oval ports and aligning them either horizontally, vertically or at an angle.  The circumference of the oval port should correspond to the circumference of a circular port of a specific diameter (e.g. Oval port with a 25.13 circumference will fit gloves designed for an 8" diameter circular port.)( see handout)  This will ensure a tight fit of the glove to the oval port. 

Oval ports can allow improved reach and do not necessarily need to be symmetrical or at the same angle.  Ergonomics means operator comfort and functionality, not aesthetic beauty and balance. 

 

GLOVE MATERIAL SELECTION

 During the production process considerations to determine the ideal port size and alignment, attention must be given to glove polymer selection, as this will affect port dimension decisions as well as glove thickness (gauge) and characteristics. 

 Some common questions for glove selection are:

 1.         Will the process involve potent hazardous materials, radioactive agents or sterilized products? 

2.         How will the gloves perform with process materials?

3.         Will the glovebox be under positive pressure or negative pressure? 

4.         What is the atmosphere best suited for the application? 

5.         What level of dexterity is required? 

6.         Hand Specific or ambidextrous gloves?

7.         Is Electro Static Discharge (ESD) at issue? 

8.         What level of cleanliness is required?

9.         Is there a sterilization cycle?

10.       How frequently must the gloves be changed?

 The selection of the proper glove material will be heavily influenced by user safety, product potency, cost, sense of touch, variety of users and comfort.  An important place to start is Material Safety Data Sheet or MSDS.  This document can help engineers determine the level of risk to humans and the proper handling techniques for the materials in question.  Cross referencing the active and inert ingredients and process materials with glove polymer/chemical compatibility charts, glovebox designers can have an initial idea of available glove options.  

Further testing with the possible glove materials and the products being handled should be done "in house" to determine the glove's ultimate suitability for the applications in question.  Many of the standard tests outlined in the ASTM (American Society for Tests and Measures) can be used for certain tests or as guidelines for testing application-specific materials with the polymers of choice. 

 

NATURAL RUBBER LATEX                                                                     (Polyisoprene)

Natural Rubber offers the technician a softness unavailable with other synthetic polymers.  Resists most moderate chemicals, wet or dry, organic acids, alcohols, ketones, aldehydes.  Attacked by ozone, strong acids, fats, oils, greases, most hydrocarbons.

Tensile strength:  about 4000psi:

 

NEOPRENE  (Chloroprene)                                                                           (Chloroprene polymer, Butadiene)

General purpose elastomer.  Resists moderate chemicals and acids, ozone, oils, fats, greases, many oils and solvents.  Attacked by strong oxidizing acids, esters, ketones, chlorinated aromatic and nitro hydrocarbons.

Tensile strength:  about 3000psi

 

NITRILE                                                                                            (Butadiene, Acrylonitrile Copolymer)

Great solvent resistance.  Very durable with excellent puncture resistance.  Resists many hydrocarbons, fats, oils, greases, hydraulic fluids, chemicals.  Attacked by ozone, ketones, esters, aldehydes, chlorinated and nitro hydrocarbons.

Tensile strength:  about 6000psi

 

HYPALON                                                                                         (Chlorosulfonated Polyethylene)

Good ozone, heat, soil and abrasion resistance.  Good resistance to oxidizing chemicals.  State of the industry for VHP sterilization.  Similar resistance to neoprene with improved acid resistance.  Attacked by concentrated oxidizing acids, esters, ketones, chlorinated aromatic and nitro hydrocarbons.

Tensile strength:  about 6000psi

 BUTYL                                                                                               (Isobutlene, Isoprene)

Very good gas permeation resistance, ozone and heat resistance.  Degraded by aromatic hydrocarbons.

Best barrier to water vapor, gases and certain toxic chemicals.  Flexible even at low temperatures.  Resists animal and vegetable fats, oils, greases, ozone, strong oxidizing chemicals.  Attacked by Petroleum solvents, coal tar solvents, aromatic hydrocarbons.

 EPDM (TERPOLYMER)                                                                   (Ethylene Propylene)

Soft with ozone and oil resistance.  Resists animal and vegetable oils, ozone, strong oxidizing chemicals.  Attacked by mineral oils and solvents, aromatic hydrocarbons.

 VITON, FLUOREL  (FLUOROELASTOMER)                    (Vinylidene fluoride, Chlorotrifluoroethylene)

Acid, Solvent and heat resistant.  Degraded by ketone solvents.

Resists all aliphatic, aromatic and halogenated hydrocarbons, acids, animal and vegetable oils.  Attacked by ketones, low mole weight esters and nitro containing compounds.

 Certain models of gloves are lead-loaded for radiation shielding.  Other models have combined properties such as the Hypalon coated Neoprene gloves.  Dual thickness neoprene offers superior touch sensitivity.  Also available:  low sulfur neoprene, latex, blue divetex, nitrile and PVC.

Hypalon and Viton are registered trademarks of EI DuPont.

Flourel is a registered trademark of 3M.  

ONE-PIECE FULLY DIPPED DRYBOX GLOVES

 Drybox glove materials are generally available in two gauges, 15mil (.015") and 30mil (.030").  This allows for a certain amount of flexibility when determining the protection requirements for handling materials and the level of dexterity required. 

 With potent applications where gross motor skills are used, a thirty mil glove will offer the most protection and the longest life.  When fine motor skills are required and the potency of the materials is less hazardous, a "lighter" gauge glove can be used.  Sizing on the one piece, fully dipped gloves are industrial sized at 8.5, 9.75, and 10.5.  Ambidextrous and hand specific styles are available in most of the fully dipped polymers.

 One piece glove solutions are ideal for potent situations requiring total containment.  Since glovebox gloves evolved from potent containment situations, industry standard, one-piece solutions continue to be popular in many applications.  One-piece solutions also provide the only solution which offers complete single-polymer protection when the application requires equal protection for the sleeve and the hand portion.  

REPLACEABLE HAND DRYBOX GLOVE COMBINATIONS

 Certain applications which called for thinner gloves or gloves of unique polymer or size requirements have driven the replaceable hand drybox glove market.  Cost benefits are realized when comparing the cost of replacing a one-piece, fully-dipped pair of gloves to the cost of replacing a 12" or 14" hand portion only (HPO).  The hand portion is the component of the manual access system which is most frequently exposed to the product and processes.  This factor leads to faster wear and tear on the glove and initially created the need for a two piece solution.  Also driving the two piece configuration was user comfort and cost factors.

 Today, the air-tight, liquid tight changeable hand drybox gloves have offered glovebox users flexibility in glove selection whereby high-end glove materials can be combined with less critical sleeve materials to offer equal protection with added flexibility.  While this solution is not applicable to all situations, it certainly should be considered.

 New developments in the aseptic replacement of the hand portion have made the two piece solution an even more economical alternative.  While the Glove-Under-Sleeve (GUS) aluminum ring and stainless spring connectors developed over thirty years ago are still popular today, certain glovebox OEM's have employed plastic wrist connectors with neoprene o-rings.  Potent applications with negative pressure conditions may require the glove to be discarded through the chamber.  Under these conditions, two-piece glove users are often better suited with a Glove Under Sleeve (GUS) solution where the contaminated glove can be pushed through the wrist connector into the chamber for proper disposal.

 Somewhat more costly, the Glove Over Sleeve (GOS) connection is suited for aseptic and sterile glove changes where the glove must be pulled through the sleeve to the outside without breaking containment.  

ACCORDION/BELLOWS STYLE SLEEVES

 The accordion bellows sleeve/glove combination has proved useful to the containment industry for over 30 years.  It was originally designed for several reasons including:

            a.         prevention of "blow-back" in positive pressure environments.

            b.         ergonomic design holds sleeve off of the operators arms

            c.         air-flow inside sleeve contributes to comfort factor

            d.         heavy gauge (50 mil) protects user

 The bellows style is available in a one-piece bonded glove/sleeve combination or is available in the classic replaceable hand drybox glove.  The one piece is better suited for potent hazardous materials handling while the replaceable hand style offers the economic savings of changing the glove while keeping the sleeve.  Accordion sleeves also allow for a more complete cleansing or sterilization cycle by eliminating folds and creases and allowing even flow run-off.

 The standard 8" diameter port size has been adapted to fit 6", 10" and 12" port sizes and like all drybox gloves, it can stretch to fit an oval port of equal circumference. 

   

STORAGE

 All elastomers degrade over time  The aging characteristics of specific polymers is determined by the chemical structure of the polymer and by anti-degrading additives.  Gloves should be stored in their original shipping box in a dry place.  Sixty to Eighty degrees is an optimum storage temperature range.  Folds or creases can accelerate the aging and compromise the integrity of the sleeve.  

Ultra violate light and ozone tend to accelerate the degradation of elastomers.  Low temperatures stiffen elastomers and can contribute to cracking.  High temperatures accelerate aging which also results in loss of physical strength.  

 

TESTING AND EVALUATING

 Glovebox gloves require testing before selection as well as prior to use.  As mentioned earlier, polymers age differently under certain circumstances.  It is wise to test the gloves or sleeve/glove combination prior to use in order to assure user safety and product protection.

 After examining the criteria of port alignment, the compatibility of gloves with processes, and the style of glove to be used, it is suggested that the engineer conduct "in house" tests on the glove material.  Many of the ASTM standards can be employed to test the materials for the following:  

            1.         Resistance to corrosive atmospheres and environments

            2.         Radiation degradation

            3.         Tear strength

            4.         Puncture resistance

            5.         Radiation shielding

            6.         Manual dexterity

 Prior to use, the technician also needs to test the product for integrity.  A visual check and a leakage test by filling the product with air is sufficient at this stage.  If all checks out the glove is installed and the cycle begins. 

 Leak testing is done at the factory level by using electrodes placed in water and charging to 5000 volts and 10,000 volts for 15mil and 30mil gloves respectively.  If the electricity passes through, the gloves will fail.  There are so many layers on these gloves that leakage is hardly a factor and the visual inspection will determine where possible problems may arise.  

After installation, a pressure check is done on the chamber with a helium test to verify the seals.  This is typically done with 90% helium and the mass spectrometer is set at 10-6 cc/min.   Sometimes Argon is used for certain welding applications.

 Some other glovebox manufacturers will snoop or a soap bubble test to isolate the leakage.  At any rate, it is important to isolate the leak and rectify the situation with the proper replacement gloves and to determine at what level the defect is occurring (production, Q.C., storage, handling, installation).

 Special thanks for assisting with this paper go to the following individuals:

 Mr. William J. Renehan

Mr. William G. Renehan

Mr. Fred Sebode

Mr. Steve Chunglo

Mr. Russ Kraniak

Mr. Rodney Smith

 

REFERENCES

 1.  Rahe, Hank; "Barrier Isolation Technology Laboratory to Production"; Cleanrooms '95 East Proceedings; April 1995.

 ASTM STANDARDS

 C852-93          DESIGN CRITERIA FOR PLUTONIUM GLOVEBOXES

D2000-90        STANDARD CLASSIFICATION FOR RUBBER PRODUCTS IN AUTO                                                   APPLICATIONS

D395               TEST FOR RUBBER PROPERTIES (COMPRESSION SET)

D412               TEST FOR THERMO PLASTIC RUBBER AND ELASTOMERS (TENSION)

D1777             THICKNESS OF TEXTILES

E1003              HYDRA STATIC LEAK TESTING (pressure; leak detection)

E515                BUBBLE EMISSION TEST (Leak detection)

E1002              ULTRA SONIC TECHNIQUES (LEAK DETECTION)

ES21                BLOOD BORNE PATHOGENS

ES22                BLOOD BORNE PATHOGENS

F 903               RESISTANCE OF CLOTHING TO PERMEATION BY LIQUIDS

 CFR METHODS

606, 809, 820

TITLE 21 PARTS. 58, 210, 211, 212

 

Note:

 The previous pages are offered as a general guide and indication of the suitability of various elastomers in use today with certain materials.  The resistance and degradation notes are based on published literature of various polymer suppliers and rubber manufacturers but in some cases, they are the opinion of experienced compounders.  Thus, there is no guarantee of their accuracy and we assume no responsibility for  the use thereof.  Several factors also influence the performance of the polymers in this report.  It is important to consider the temperature of service, the conditions of service, the grade of the polymer and the compound itself.  In light of the above factors, it is best to test all materials for your specific applications.

 RAR

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