Presented at the Division of Chemical Health and Safety technical sessions at the Denver 2011 American Chemical Society Meeting

1. Compressed Gases: The Orphan Hazard Neal Langerman Advanced Chemical Safety San Diego, CA

2. Compressed Gas Considerations Basic assumption: “Everyone knows how to handle CG correctly” Basic practice: “Secure the cylinder” and all is cool Reality: Neither of the above is correct. Purpose today: To remind you that compressed gases are chemicals too, which have a unique property (HP) Point out a few of the standard guidelines 2 Compressed Gas Safety

3. Compressed Gas Considerations The package side of a CG system is well engineered Highly regulated in transit and use The end-user side is at the mercy of the user Engineering is arbitrary Oversight is limited System failure rate is low Compressed Gas Safety 3

4. Compressed Gas Considerations 4 Compressed Gas Safety

5. Compressed Gas Considerations Based on Headline Data 5 Compressed Gas Safety

6. Compressed Gas Considerations 6 Compressed Gas Safety

7. Compressed Gas Considerations 7 Compressed Gas Safety

8. Compressed Gas Considerations 8 Compressed Gas Safety Oxidizer & Flammable

9. Compressed Gas Considerations 9 Compressed Gas Safety

10. Compressed Gas Handling Guidelines Compressed Gas Association Publication Locator http://www.cganet.com/customer/publication.aspx?AspxAutoDetectCookieSupport=1 P-1 Safe Handling of Compressed Gases in Containers P-12 Safe Handling of Cryogenic Liquids HB Handbook of Compressed Gases http://www.scribd.com/doc/55730782/Nicollet-Compress-Gas-Plan (a very good CG Safety Plan) 10 Compressed Gas Safety

11. Compressed Gas Handling Guidelines Chemical Hazards Corrosive Flammable, including pyrophoric (eg: silane) Toxic, including “super” toxic (eg: arsine) Oxidizer Cryogenic 11 Compressed Gas Safety

12. Compressed Gas Handling Guidelines Physical States Compressed: Nonflammable material or mixture that is contained under pressure exceeding 41 psia (3 bar) at 70°F (21°C) or any flammable or poisonous material that is a gas at 70°F (21°C) and 14.7 psia (1 bar) or greater. Compressed, non-liquified Compressed, liquified Compressed, in solution 12 Compressed Gas Safety

13. Compressed Gas Handling Guidelines Compressed gas cylinders should be secured and stored upright in a well-ventilated, cool, dry, secure area that is protected from the weather, free of combustible materials, and located away from heavily traveled areas, emergency exits, and areas where salt or other corrosive materials are present. Cylinders must be clearly labeled as to their contents. They should also be marked when empty. Fuels and oxidants should not be stored together. Cylinders should never be dropped, dragged, or rolled. Hand-trucks should be used for moving cylinders from one location to another. 13 Compressed Gas Safety

14. Compressed Gas Handling Guidelines Engineering Controls - each gas application will have it's own engineering controls depending on the types of hazards and application. Examples of engineering controls are: Fume hoods Gas Cabinets Ventilation systems Smoke detectors Sprinkler systems Flow Restrictors Scrubbers Leak Monitors Gas cylinder storage areas 14 Compressed Gas Safety

15. Compressed Gas Handling Guidelines Administrative Controls - compressed gas program administrative controls include: Employee training Segregation of gas containers Inspections and audits Signs Assignment and use of PPE Identification of authorized employees Procedures for receipt, use and storage Compressed Gas Control Bands Cylinders in labs or equivalent Process Risk Assessment is performed 15 Compressed Gas Safety

16. Compressed Gas Safety Levels CG Safety Level 1 – use of an inert gas in a situation which may cause an oxygen deficiency (eg: nitrogen, argon) CG Safety Level 2 – use of a flammable, low toxicity simple asphyxiant (eg methane, propane) CG Safety Level 3 – use of pyrophoric gases or liquids (eg: silane) CG Safety Level 4 – use of corrosive, toxic or highly toxic gases (eg: HCl, H2S, Arsine) CG Safety Level – special – use of compressed gases inside chemical fume hoods or other unique set-ups 16 Compressed Gas Safety

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22. Table Notes Base application on formal process risk assessment Equipment placed in chemical fume hood qualifies as ventilated enclosure May be required by local code A CGSL-4 system using a highly toxic gas in a chemical fume hood must be placed inside a dedicated exhausted enclosure For CGSL-4 only 22 Compressed Gas Safety

23. Compressed Gases: Conclusions Well engineered systems Apparent low priority Higher probability for end-user misuse Raise your level of end-user awareness Prevent a problem 23 Compressed Gas Safety

24. Keep your pressure low … Questions??? 24 Compressed Gas Safety