Home Podcasts THMG090 – Cylinders 2

THMG090 – Cylinders 2


In this episode, Bob and Mike continue their discussion of cylinders.

Please subscribe to all of our hazmat shows: The Haz Mat Guys Podcast, THMG Hot Wash, THMG Instructor’s Corner and The Haz Mat Guys Nation Roundtable. You can now check us out doing the show live on Webinarjam.com periodically. We also do a weekly roundtable discussion with experts from around the country on YouTube Live under The Haz Mat Guys Nation every Tuesday night at 21:15 EST.

Complete Show Notes

4:20 Cylinder Standards and Laws

  • Most of these laws are developed by the ISO (International Organization for Standardization)
  • Valving tells you more about what’s in the cylinder than anything else
  • Gas cylinders are monitored by the United States DOT
  • 49 CFR, Section 173 mandates the use of hazardous materials placards during shipment
  • OSHA creates and enforces laws protecting workers who handle cylinders and regulations surrounding the cylinders themselves

6:45 Compressed Gas Association (CGA) Numbers and the Code of Federal Regulations (CFR)

  • We need to be able to assess the situation – how are they being stored? Are they immobilized? – this is all covered in CGA 3.4.4 and 29 CFR 1910.101b
  • We need to be able to see if something’s not right and prepare to address those issues
  • CGA 3.6.6 – Determine whether the cylinders are being stored near highly flammable substances
  • CGA 3.5.1 – Are the cylinders being stored away from electrical connections, gas flames, sources of ignition, flammable solvents, combustible waste materials, etc.?
  • CGA 3.3.3 – You must have flammable gasses separated from oxidizing gasses within the storage are
  • CGA 3.5.3 – Are oxygen and fuel cylinders separated by a minimum of 20 feet when in storage?
  • These are federal regulations – your state and local regulations may be different
  • These are the minimum regulations – you can make things safer, but you can’t fall below these standards
  • CGA 3.5.5 – storage rooms have to be fire resistant and shouldn’t be located in sub-levels (like basements)
  • CGA 3.3.7 and 29 CFR 1910.1b – They should also be in a secure area with temperatures below 125 degrees Fahrenheit and away from sources of ignition
  • Essentially, we want to keep them in a cool, dry, ventilated area
  • Cylinders also need to be stored away from incompatibles – for example, you don’t want a peroxide cylinder next to an inorganic cylinder
  • If there’s rusting, you’re dealing with a thinning of the wall – these walls are specifically designed for really high pressure (i.e. 3,000 psi) – the air is looking for a place to get out

13:15 Cylinder Valving

  • Provides you with some of the most important information you can gather from the cylinder
  • There are a ton of different types of valves out there – impossible to talk about all of them
  • Condensed Compressed Gas Handbook is a helpful resource – full of helpful information on valving (you can also use your phone)
  • Valves and threading
    • The valve will be stamped with a number – you’ll also see the threads
    • Threading tells us a lot – regular vs. reverse, inside threads, outside threads, etc.
    • Look at the neck and how it’s tied into the cylinder
    • Look at the on/off valve on the actual valve – this also gives us a lot of helpful information
    • POL valves have a notch in the nut – quick way of identification
  • Pressure reduction devices
    • We’re not concerned about vacuum breakers since we’re not dealing with tankers
    • You may have a spring-loaded breaker (burps and recedes) or a rupture disk (bursts)
    • You’ll sometimes see thermal blow-offs – often happens if cylinders are stacked

17:15 Specifics on CGA Numbers

  • CGA numbering allows for standardization across cylinders, valving, and products that connect to valves
  • Compressed gasses that come out of cylinders are required to go through very specific valving
  • Some gasses only have one type of valve, while others have multiple types to choose from
  • Valves are regulated based on what their task is and the type of cylinder they’re connected to
  • CGA number is stamped on the side of the valve – they’re usually made of soft brass that can be stamped easily
  • You can refer to CGA numbers in the Compressed Gas Handbook or just Google it – always check multiple sources to make sure the information is correct
  • Looking up the CGA number helps us classify what’s probably in the cylinder and allows us to figure out what the cylinder was designed to hold

23:15 Medical Gasses

  • Cylinders designed to hold medical gasses have a very unique set of valving
  • Pin index connection – system that makes it impossible to cross-thread the valve
  • These valves have holes in them with pins that line up on the adapter – this means only that specific adapter made for that specific gas can attach to that valve
  • If they don’t match up properly, you can still remove gas, but there’s no way to get into the regulator
  • Designed to ensure someone isn’t inadvertently given the wrong medical gas
  • There are specific CGA numbers dedicated to medical gas cylinders

Have a question? Send an email to feedback@thehazmatguys.com or leave a message on our Haz Mat Guys comment hotline: 843-628-1484

Show Sponsors
Related Episodes

The Hazmat Guys

Author: The Hazmat Guys