DuPont Permeation Guide

Transcription

1 DuPont Guide Tychem Tyvek

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3 INTRODUCTION - Chemical What is permeation? is the process by which a potentially hazardous chemical moves through a material on a molecular level. can be represented by the following simplified diagram (ig. 1). ig. 1 - On the challenge side of the test cell the outside fabric surface is exposed continuously to the challenge chemical. The sampling side of the test cell is analytically monitored. The normal test duration is 480 minutes. An explanation of the parameters which describe the permeationperformance of a barrier is given below. rate ➀ Sorption of molecules of liquid onto the contracted (outside) surface of the fabric. ➁ Diffusion of the sorbed molecules across the fabric. A permeation rate indicates the mass of the chemical in micrograms, which can be transferred through one square centimetre of the fabric in one minute. The unit is µg/(cm² min). detectable permeation rate (MDPR) Measuring permeation ➂ Desorption of the molecules from the opposite (inside) surface of the fabric. The resistance of a protective clothing fabric to permeation by a chemical can be determined by testing a fabric against a challenge chemical EN ISO 6529 (method A and B), ASTM -739 or EN or these methods a two-chambered test cell is used. The test specimen is positioned between the two sections of the cell. ig. 2 - test cell ill level Reservoir for challenge chemical Test specimen To analyzer lushing of chamber or discrete sampling The lowest rate of permeation that is measurable is called the minimum detectable permeation rate (MDPR). The MDPR can vary depending on the sensitivity of the analytical device for the given substance. detectable permeation rates can be as low as µg/(cm² min) in certain cases. Breakthrough detection time ( breakthrough time) The breakthrough detection time or actual breakthrough time is the time elapsed between initial contact of the chemical with the outside surface of the protective clothing fabric and its detection at the inside surface. breakthrough has taken place when the minimum detectable permeation rate has been reached. A breakthrough detection time of more than 480 minutes indicates that the challenge chemical did not reach the minimum detectable permeation rate during the test time of 480 minutes. 1

4 There is the possibility that a breakthrough at a lower permeation rate than the minimum detectable permeation rate has in fact taken place. To be able to interpret the actual breakthrough time the minimum detectable permeation rate should be indicated. Normalized permeation rate To be able to compare permeation data, the breakthrough time is reported at defined permeation rates. According to ASTM -739 the normalized breakthrough detection time is reported at a permeation rate of 0.1 µg/(cm² min). According to EN the normalized breakthrough detection time is reported at a rate of 1.0 µg/(cm² min). The test method EN ISO 6529 provides the choice of two normalized permeation rates for reporting the results: 0.1 µg/(cm² min) or 1.0 µg/(cm² min). ig. 3 - Typical permeation cell results rate µg/(cm 2 min) Performance classes * Chemical protective clothing is classified into six classes based on a normalized permeation rate of 1.0 µg/(cm² min). Table 1 Normalized breakthrough time at a EN Class permeation rate of 1.0 µg/(cm² min) in minutes > 10 1 > 30 2 > 60 3 > > > * : Protective clothing against chemicals - test methods and performance classification of chemical protective clothing MDPR ASTM 739 EN ISO 6529 EN 369/374-3 EN ISO 6529 SSPR Time (min) 480 Min Steady state permeation rate (SSPR) The constant permeation rate that occurs after reaching equilibrium is called the steady state permeation rate. data table The permeation data table for the C, C2, and 2 fabrics is organized alphabetically. or each chemical the CAS-number and the physical state is listed. CAS-number is a unique numerical identifier created and assigned to a chemical substance by the Chemical Abstract Society. The physical state describes the state in which the chemical has been tested. Unless otherwise stated, the tests were performed with pure chemicals under laboratory conditions at room temperature and environmental pressure. The table shows the following data for each chemical: breakthrough time in minutes Normalized breakthrough time at 0.1 µg/(cm² min) in minutes Normalized breakthrough time at 1.0 µg/(cm² min) in minutes Performance class Steady state permeation rate in µg/(cm² min) detectable permeation rate in µg/(cm² min).

5 Interpreting permeation data Chemical Name Physical State CAS-No. Barrier to a range of organic and highly concentrated inorganic chemicals Detection minutes minutes minutes µg/(cm².min) µg/(cm².min) Example 1 Sulphuric acid (98%) L > 480 > 480 > < Example 2 Cresol-o L Example 3 Thionyl chloride L imm imm Example 1: Sulphuric acid, CAS , 98 % * is exposed to Sulphuric acid, 98 % for a test duration of more than 480 minutes. No breakthrough has taken place at the minimum detection rate of 0.01 µg/(cm² min), the normalized breakthrough time at 0.1 µg/(cm² min) and 1.0 µg/(cm² min). The breakthrough time for these permeation rates are reported with more than 480 minutes. Based on the results for the normalized breakthrough time at 1.0 µg/(cm² min) the resistance to permeation is classified into class 6. The permeation did not reach equilibrium at a measurable level. Therefore the steady state permeation rate is below the minimum detectable permeation rate (0.01 µg/(cm² min). There is the possibility that Sulphuric acid permeates the barrier, but at a lower rate than 0.01 µg/(cm² min). Based on the permeation data, fabric can be considered as offering a chemical barrier to liquid 98%* Sulphuric acid. The selected fabric should then be taken into the next step of the garment selection process as part of the workplace risk assessment. Example 2: o-cresol, CAS is exposed to o-cresol, CAS for a test duration of more than 480 minutes. Breakthrough has taken place at the minimum detection rate of 0.01 µg/(cm² min) after 124 minutes. The normalized breakthrough time at 0.1 µg/(cm² min) has been reached after 180 minutes and the normalized breakthrough time at 1.0 µg/(cm² min) after 206 minutes. Based on the results for the normalized breakthrough time at 1.0 µg/(cm² min) the resistance to permeation is classified into class 4. The permeation reached equilibrium at a rate of 2.7 µg/(cm² min) between 206 and 480 minutes. Based on the permeation data, fabric shall be considered as offering a limited barrier only to o-cresol. fabric may be considered in the next step of the garment selection process as part of the workplace risk assessment, but breakthrough does occur. Careful attention must be paid to the working temperature, exposure time, contaminated suit area, chemical toxicity and working practices. Example 3: Thionyl chloride, CAS Based on permeation data is a limited barrier to Thionyl chloride, CAS The minimum detection rate of 0.01 µg/(cm² min) and the normalized breakthrough time at 0.1 µg/(cm² min) are reached immediately. The normalized breakthrough time at 1.0 µg/(cm² min) has been reached after 15 minutes. The steady state permeation rate of 101 mg/(cm² min) indicates that high quantities will permeate. Based on the permeation data, fabric shall be considered as an insufficient barrier to Thionyl chloride. or certain tasks, whereby the exposure risk is highly unlikely and the employee is trained to remove the PPE upon eventual exposure, then garments made of could be considered in the risk assessment, but extreme caution must be applied. If possible, identifying a fabric which offers a higher chemical permeation barrier would be a recommended safer approach. * Warning: presence of vapours must be addressed in the garment risk assessment. 3

6 Important note: Please use the permeation data as part of the risk assessment to assist the selection of a protective fabric, garment or accessory suitable for your application. Working conditions, exposure conditions (e.g. temperature, pressure, concentration, physical state), and the toxicity data for the chemical need to be taken into account. is not the same as safe wear time. alone is insufficient to determine how long a garment may be worn once the garment has been contaminated. Safe user wear time may be longer or shorter than the breakthrough time depending on the permeation behaviour of the substance, the toxicity of the substance and the exposure conditions. s are indicative of the barrier performance, but results can vary between the test methods and laboratories. A different temperature may have significant influence on the breakthrough time. typically increases with temperature. data are usually measured for single chemicals. The permeation characteristics of mixtures can deviate considerably from the behaviour of the individual chemicals. The permeation data published in this document have been generated for DuPont by independent accredited testing laboratories the test method applicable at that time*. The data is typically the average of three samples tested. * EN369, ASTM 739, EN or EN ISO 6529 (method A and B). Although the fabric itself may offer a barrier to a certain range of gaseous chemicals, chemical protective clothing category III type 3 made of C,, C2 or 2 is not gastight. In case you need a barrier to gases or vapours, please take a chemical protective clothing category III type 1, such as TK into consideration. C/C2 and /2 garments C Standard and C2 model CHZ5 are certified as chemical protective clothing category III type 3B, 4, 5 and 6 and offer a barrier to pressurized liquids up to a pressure of 2 bar. They are a barrier to a range of concentrated inorganic chemicals. Standard and 2 model CHZ5 are certified as chemical protective clothing category III type 3B, 4, 5 and 6 and offer a barrier to pressurized liquids to a pressure up to 3 bar. They are a barrier to a range of organic and highly concentrated inorganic chemicals. DuPont tm C, C2, and 2 garments have stitched and overtaped seams. The seam tape is a special barrier tape which offers the same permeation barrier performance as the fabric itself. data for C fabric is applicable for the reinforced C2 fabric and permeation data for fabric is applicable for the reinforced 2 fabric. data for chemical warfare agents data for chemical warfare agents is available on request. Contact our Techline: Need selection assistance? Need technical advice? No chemical permeation data for your chemical? DuPont experts can provide technical assistance with your fabric and garment selection process. Using a simple web-based questionnaire, please provide relevant information on chemicals, exposure and working conditions for a customized response. Independent permeation testing of your specific chemical with the DuPont barrier fabrics can also be facilitated. To check the most updated permeation data, please visit our website. 4

7 c/c2 and f/f2 fabrics - Data C Barrier to a range of concentrated inorganic chemicals Barrier to a range of organic and highly concentrated inorganic chemicals Chemical Name Physical State CAS No. Detection Detection minutes minutes minutes µg/(cm².min) µg/(cm².min) minutes minutes minutes µg/(cm².min) µg/(cm².min) Acetaldehyde L imm imm Acetic acid (glacial) L > 480 > 480 > < Acetone L > 480 > 480 > < Acetone cyanohydrin L > 480 > 480 > < Acetonitrile L > 480 > 480 > < Acetyl chloride L > 480 > Acrolein L imm 48 > Acryl amide (50%) L > 480 > 480 > < Acrylic acid L > 480 > Acrylonitrile L imm 8 > Adiponitrile L > 480 > 480 > < Allyl alcohol L imm > 480 > Allyl chloride L > Ammonia (gas) G > Amyl acetate n- L > Aniline L > 480 > 480 > < Aniline, 4-trifluoromethoxy- L > 480 > 480 > < Anthracene (sat'd. in toluene) L > 480 > 480 > < Antimony pentachloride L > Arsenic (III) chloride L Benzene L > 480 > 480 > < Benzene sulfonyl chloride L > 480 > 480 > < Benzonitrile L > 480 > 480 > < Benzoyl chloride L > 480 > 480 > < Benzyl alcohol L > 480 > 480 > < Benzyl chloride L > 480 > 480 > < Benzyl cyanide L > 390 > 390 > < Bisphenol-A Diglycidyl Ether L > 480 > 480 > < Boron trifluoride dimethyletherate L > 480 > 480 > < Bromine (liquid) L imm imm KEY: = Not tested S = solid G = gaseous L = liquid imm = Immediate sat d = saturated 5

8 c/c2 and f/f2 fabrics - Data C Barrier to a range of concentrated inorganic chemicals Barrier to a range of organic and highly concentrated inorganic chemicals Chemical Name Physical State CAS No. Detection Detection minutes minutes minutes µg/(cm².min) µg/(cm².min) minutes minutes minutes µg/(cm².min) µg/(cm².min) Bromofluorobenzene 4- L > 480 > 480 > < Butadiene 1,3- (gas) G > 480 > Butanol n- L > 480 > 480 > < Butyl ether n- L > Carbon disulfide L > 480 > Carbon tetrachloride L > Chlorine (gas) G > 480 > Chloro-1,3-butadiene 2- (50% in Butanol) L > 480 > 480 > < Chloroacetic acid (68%) L > 480 > Chloroacetone L > 480 > 480 > < Chloroacrylonitrile 2- L > 480 > 480 > < Chlorobenzene L > 480 > 480 > < Chloroethanol 2- L > 480 > Chloroform L Chloromethyl methyl ether L imm 8 > Chlorosulfonic acid L > 480 > Chlorotoluene o- L > 480 > 480 > < Chlortrinitromethane L > 480 > 480 > < Chromic acid 80% (H2SO4 x CrO3) L > 480 > 480 > < Creosote L > 480 > 480 > < Cresol-o L Cumene (Isopropylbenzene) L > 480 > 480 > < Cyclohexane L > 480 > Cyclohexanone L > 480 > 480 > < Dichloroacetyl chloride L Dichloroethylether L > 480 > 480 > < Dichloromethane L imm imm imm Dichloropropene 2,3- L Diesel fuel L > 480 > Diethyl amine L > 480 > 480 > < KEY: = Not tested S = solid G = gaseous L = liquid imm = Immediate sat d = saturated

9 c/c2 and f/f2 fabrics - Data C Barrier to a range of concentrated inorganic chemicals Barrier to a range of organic and highly concentrated inorganic chemicals Chemical Name Physical State CAS No. Detection Detection minutes minutes minutes µg/(cm².min) µg/(cm².min) minutes minutes minutes µg/(cm².min) µg/(cm².min) Diethyl sulfate L > 480 > 480 > < Diethylenetriamine L > 480 > 480 > < Dimethyl acetamide N,N- L > 480 > 480 > < Dimethyl amine G > 480 > 480 > < Dimethyl aniline N,N- L > 480 > 480 > < Dimethyl dichlorosilane L > 480 > 480 > < Dimethyl formamide N,N- L > 480 > 480 > < Dimethyl nitrosamine L > 480 > 480 > < Dimethyl sulfate L > 480 > 480 > < Dimethyl sulfide L Dimethyl sulfoxide L Dioxane 1,4- L > 480 > 480 > < Epichlorohydrin L > Ethanol L > 480 > 480 > < Ethanolamine L > 480 > 480 > < Ethoxy ethylacetat L > 480 > 480 > < Ethyl acetate L > 480 > 480 > < Ethyl ether L > 480 > 480 > < Ethylene diamine L > 480 > 480 > < Ethylene dibromide L > Ethylene dichloride L Ethylene glycol L > 480 > 480 > < Ethylene oxide (gas) G luorobenzene L > 480 > 480 > < luorosilicic acid L > 480 > 480 > < ormaldehyde (10%) L > 480 > 480 > < ormaldehyde (37%) L imm imm > > 480 > 480 > < ormic acid (96%) L > urfural L > 480 > Gasoline, leaded L Mixture imm imm > KEY: = Not tested S = solid G = gaseous L = liquid imm = Immediate sat d = saturated 7

10 c/c2 and f/f2 fabrics - Data C Barrier to a range of concentrated inorganic chemicals Barrier to a range of organic and highly concentrated inorganic chemicals Chemical Name Physical State CAS No. Detection Detection minutes minutes minutes µg/(cm².min) µg/(cm².min) minutes minutes minutes µg/(cm².min) µg/(cm².min) Gasoline, unleaded L Mixture > 480 > 480 > < Hexamethylene diisocyanate L > 480 > 480 > < Hexamethylenediamine 1,6 (45 C) L > 480 > Hexane n- L > 480 > 480 > < Hexone L > 480 > 480 > < Hydrazine L Hydrochloric acid (32%) L > 480 > 480 > < Hydrochloric acid (37%) L > > 480 > 480 > < Hydrofluoric acid (48%) L > 480 > 480 > < > 480 > 480 > < Hydrofluoric acid (70%) L imm imm imm Hydrogen bromide (gas) G > 480 > 480 > < Hydrogen chloride (gas) G > 480 > 480 > < Hydrogen fluoride (gas) G Hydrogen fluoride (liquid, at 18 C) L Hydrogen peroxide (50%) L > 480 > 480 > < > 480 > 480 > < Hydroiodic acid (55%) L > 480 > 480 > < Hypophosphorus acid (50%) L > 480 > 480 > < Isophthaloyldichloride (45 C) L > 480 > 480 > < Isopropanol L > 480 > 480 > < Isopropyl amine L > 480 > 480 > < Kerosene L > 480 > 480 > < Limonene d- L > 480 > 480 > < Lupranate (MDI) L > 480 > 480 > < Mercuric I chloride (sat'd) L > 480 > 480 > < Mercuric II chloride (sat'd) L > 480 > 480 > < Mercury L > 480 > 480 > < Methacrylic acid L > 480 > 480 > < Methanesulfonyl chloride L > 480 > 480 > < Methanol L > Methoxy ethanol 2- L > 480 > KEY: = Not tested S = solid G = gaseous L = liquid imm = Immediate sat d = saturated 8

11 c/c2 and f/f2 fabrics - Data C Barrier to a range of concentrated inorganic chemicals Barrier to a range of organic and highly concentrated inorganic chemicals Chemical Name Physical State CAS No. Detection Detection minutes minutes minutes µg/(cm².min) µg/(cm².min) minutes minutes minutes µg/(cm².min) µg/(cm².min) Methoxy ethylacetat 2- L > 480 > 480 > < Methyl acrylate L > 480 > 480 > < Methyl amine G > 480 > 480 > < Methyl chloride G > 480 > Methyl chloroformate L > Methyl ethyl ketone L imm 40 > Methyl ethyl ketoxime L > 480 > 480 > < Methyl formamide N- L > 480 > 480 > < Methyl hydrazine L Methyl isocyanate L imm 4 > Methyl mercaptan G > 480 > 480 > < Methyl methacrylate L Methyl pentanedinitrile 2- L > 480 > 480 > < Methyl propanol 2- L > Methyl pyrrolidone N- L > 480 > 480 > < Methyl tert-butyl ether L > 480 > 480 > < Methyl trichlorosilane L > 480 > 480 > < Methyl vinyl ketone L > < Methylene biscyclohexylamine 4,4- L > 480 > 480 > < Methylene bromide L imm Naphthalene (sat'd in toluene) L > 480 > 480 > < Nicotine L > 480 > 480 > < Nitric acid (70%) L > 480 > > 480 > 480 > < Nitric acid (90%, fuming) L > Nitrobenzene L > 480 > 480 > < Nitrochlorobenzene o- (35-40 C) L > 480 > 480 > < Nitrogen dioxide G < 15 <15 > Nitromethane L Nitropropane 2- L > 480 > 480 > < Oleum (30% free SO3) L KEY: = Not tested S = solid G = gaseous L = liquid imm = Immediate sat d = saturated 9

12 c/c2 and f/f2 fabrics - Data C Barrier to a range of concentrated inorganic chemicals Barrier to a range of organic and highly concentrated inorganic chemicals Chemical Name Physical State CAS No. Detection Detection minutes minutes minutes µg/(cm².min) µg/(cm².min) minutes minutes minutes µg/(cm².min) µg/(cm².min) Oleum (40% free SO3) L > PCB in tranformer oil L na 324 > 480 > Pentanol 1- L > 480 > 480 > < Pentene nitrile 2- L > 480 > 480 > < Perchloric acid (70%) L > 480 > 480 > < Phenol (85%) L Phosgene G > 480 > 480 > < Phosphine G imm imm > Phosphoric acid (85%) L > 480 > 480 > < > 480 > 480 > Phosphorus oxychloride L > 480 > < Phosphorus trichloride L > 480 > Picoline 2- L > 480 > 480 > < Picoline 3- L > 480 > 480 > < Potassium chromate (sat'd) L > 480 > 480 > < > 480 > 480 > < Propylamine n- L > Propylene oxide 1,2- L Pryridine, 2-fluoro-6-(trifluoromethyl) L > 480 > 480 > < Pyridine L > 480 > 480 > < Pyrrolidine L Silane G > 480 > 480 > < Silicon tetrachloride L > 480 > 480 > < Sodium acetate (sat'd) L Sodium cyanide (45%) L > 480 > 480 > < Sodium hydroxide (42%) L > 480 > 480 > < Sodium hydroxide (50%) L > 480 > 480 > < > 480 > 480 > < Sodium hydroxide (solid) S Sodium hypochlorite (13% active Chlorine) L > 480 > 480 > < Sodium hypochlorite (30%) L > 480 > 480 > < Styrene L > 480 > Sulphur dioxide G KEY: = Not tested S = solid G = gaseous L = liquid imm = Immediate sat d = saturated 10

13 c/c2 and f/f2 fabrics - Data C Barrier to a range of concentrated inorganic chemicals Barrier to a range of organic and highly concentrated inorganic chemicals Chemical Name Physical State CAS No. Detection Detection minutes minutes minutes µg/(cm².min) µg/(cm².min) minutes minutes minutes µg/(cm².min) µg/(cm².min) Sulphuric acid (50%) L > 480 > 480 > < Sulphuric acid (98%) L > 480 > 480 > < > Sulphuryl chloride L > 480 > 480 > < Tetrachloro-bisphenol-A 2,2',6,6'- S > 480 > 480 > < Tetrachloroethylene 1,1,2,2- L > 480 > Tetrahydrofuran L > Thioglycolic acid L > 480 > 480 > < Thionyl chloride L imm imm Tin chloride, mono-n-butyl L > 480 > 480 > < Tin chloride, tri-n-butyl L > Titanium tetrachloride L > 480 > 480 > < Toluene L > 480 > 480 > < Toluene-2,4-diisocyanate (80%) L > 480 > 480 > < Toluidine o- L > 480 > 480 > < Trichloroacetic acid L > 480 > 480 > < Trichloroacetone 1,1,3- L > Trichlorobenzene 1,2,4- L > 480 > 480 > < Trichloroethane 1,1,2- L Trichloroethanol 2,2,2- L > 480 > 480 > < Trichloroethylene L > 480 > 480 > < Trichlorophenylsilane L > 480 > 480 > < Trifluoroacetic acid L > 480 > 480 > < Trifluoromethansulfonic acid L > 480 > 480 > < Trimethyl quinone (at 30 C) L > Vinyl acetate L Vinyl chloride G imm > 480 > Vinylidene chloride L > 480 > 480 > < Xylene (mixed isomers) L > KEY: = Not tested S = solid G = gaseous L = liquid imm = Immediate sat d = saturated 11

14 TYVEK ABRIC - Data data for Tyvek Please find below a selection of permeation data for Tyvek White 1422A / 1431N. Tyvek, extremely tough, tear and abrasion resistant, offers strong barrier against particles and resists low-pressurized water-based liquid chemical splashes. Tyvek Classic Xpert is the chosen category III protection against solid particles larger than 1 μm (Type 5), and mist, i.e. low-level liquid aerosols from water-based chemical spray (Type 6). Tyvek Classic Plus is a chemical protective clothing category III type 4B, 5 and 6, providing high barrier against many inorganic chemicals in low concentrations and particles larger than 1 micron. With its overtaped seams, this suit is ideal for toxic dry particulate environments or to prevent liquid penetration through seams. vs. penetration and repellency is not the same as penetration. Liquid chemical penetration is a physical process whereby a liquid penetrates a fabric by passing through pores or holes in the fabric. The European standard EN ISO 6530 (referred to as the gutter test ) measures liquid penetration through a fabric and liquid repellency by a fabric. Penetration & repellency tests, such as the gutter test, are typically short duration tests of 1 minute. abrics may show high repellency and penetration indices to certain chemicals, but when exposed for several minutes will allow the chemical to permeate. 12

15 TYVEK ABRIC - Data Chemical Name Physical State CAS No. Normalized at 0.1 µg/(cm².min) Normalized at 1.0 µg/(cm².min) Tyvek Classification according to Detection minutes minutes minutes µg/(cm².min) µg/(cm².min) Glycerol L > 480 > Hydrochloric acid (16%) L Hydrochloric acid (30%) L imm imm imm Hydrogen peroxide (10%) L > 480 > 480 > < Hydrogen peroxide (30%) L imm 15 > Mercuric II chloride (sat'd) L > 480 > 480 > < Nitric acid (10%) L > 480 > 480 > < Nitric acid (30%) L Phosphoric acid (50%) L > 480 > 480 > < Potassium chromate (sat'd) L > 480 > 480 > < Potassium hydroxide (40%) L > Sodium acetate (sat'd) L > 480 > 480 > < Sodium hydroxide (40%) L > 480 > 480 > < Sodium hydroxide (50%) L > Sodium hydroxide (solid) S > 480 > 480 > < Sodium hypochlorite (13% active Chlorine) L > 480 > 480 > < Sodium hypochlorite (sat'd) L > 480 > 480 > < Sulphuric acid (18%) L > Sulphuric acid (30%) L Sulphuric acid (50%) L KEY: = Not tested S = solid G = gaseous L = liquid imm = Immediate sat d = saturated 13

16 or more information on our support services, please contact: DuPont Personal Protection DuPont de Nemours Luxembourg S.àr.l. L-2984 Luxembourg Tel.: (international toll-free) Or visit our website at: Techline: Tel.: Website: Disclaimer This information is based upon technical data that DuPont believes to be reliable. It is subject to revision as additional knowledge and experience becomes available. DuPont does not guarantee results and assumes no obligation or liability in connection with this information. It is the user s responsibility to determine the level of toxicity and the proper personal protective equipment needed. This information is intended for use by persons having the technical expertise to undertake evaluation under their own specific end-use conditions, at their own discretion and risk. Anyone intending to use this information should first check that the garment selected is suitable for the intended use. The end-user should discontinue use of garment if fabric becomes torn, worn or punctured, to avoid potential chemical exposure. Since conditions of use are beyond our control, we make no warranties, expressed or implied, including but not limited to warranties of merchantability or fitness for a particular purpose and assume no liability in connection with any use of this information. This information is not intended as a licence to operate under or a recommendation to infringe any patent or technical information of DuPont or other persons covering any material or its use. L / Copyright DuPont The DuPont Oval logo, DuPont TM, The miracles of science TM, and Tyvek are trademarks or registered trademarks of E. I. du Pont de Nemours and Company or its affiliates. All rights reserved.