Compressed Gas Cylinder Safety

Move Cylinders Out of Corridors

In August 2015, the Ad Hoc Safety Committee directed the EHS Office to initiate a campaign to move compressed gas cylinders out of the corridors. The EHS Coordinators and their teams are asked to:  

  • Present this topic at a rep meeting before you start inspections. Modify the attached slides. (scroll down)
  • Encourage EHS reps to use the Airgas inventory and check if there any cylinders in their lab that can be returned. Also check if all of the cylinders in the corridor belong to their lab.  Often they belong to a nearby lab or to a lab that moved.   
  • Download the B2P quickcards (scroll down) to verify the Airgas inventory information
  • Educate reps to use the webpage to request that Airgas pick up unneeded cylinder(s) when you don't need to order cylinders. This webpage can also be used to report cylinders that have been relocated

Guidelines for securing cylinders

Restrain compressed gas cylinders securely with a chain, belt or stand at all times to prevent them from falling over. If a cylinder falls, it may shear off its valve, and the escaping high-pressure gas has been known to propel the cylinder like an unguided rocket (view Mythbusters video) It can smash through masonry walls, go long distances and ricochet.

Secure the cylinder above its center of gravity (~2/3 up the cylinder). If the chain or belt is too low or too high, it will not hold the cylinder if it starts to fall. The chain should not be around the neck of the cylinder, since the cylinder could slide under the chain. The chain should not hang below the mid point of a cylinder, since it could topple over the chain.

Protect the cylinder valve with a securely attached valve cap whenever a cylinder is being moved, and at all other times unless a regulator is attached to the cylinder.

Store flammable gases separately from oxygen and combustible materials by at least 20 feet. Highly toxic (health rating 4), pyrophoric gases, nitrous oxide, and other DHS gases should be secured from unauthorized access.


Cylinder wall brackets with straps/ belts

Create a service request in Atlas for the Department of Facilities (DOF) to obtain and mount standard wall brackets. These need to be securely attached to hold the weight of the cylinders.  Or you can order wall brackets from VWR or Airgas and then create a service request in Atlas for DOF to mount your brackets.

Wall brackets are strong enough to hold two cylinders strapped together. However, when the strap is taken off to move one cylinder, then both could fall over.


Inspect Straps

Follow the steps in the attached Cylinder Strap Inspection Tips.  If necessary, order a replacement from any of the vendors listed on the attached comparison of cylinder strap/holder (scroll down).  Polyester or nylon cylinder straps will resist fraying better than the older straps that are made out of fabric.

If you find a defective Airgas strap or a questionable Airgas strap,

  1. Please send a photo of strap, bldg-room number and the contact person’s information to  Request a free replacement and copy your EHS Coordinator.
  2. Replace the Airgas strap with a spare strap that is in good condition or use a chain.
  3. Keep the Airgas strap unless John Jordan says he doesn't need it.


Bench type cylinder clamps

These can be obtained from any of the vendors listed on the cylinder strap/bracket attachment (scroll down). The lab bench, which the cylinder is mounted to, must be strong enough for the size and weight of the cylinder.


Floor stands for Cylinders (no wall space needed)

We recommend the type that has a bracket, which can be turned over to change sizes depending on the diameter of the cylinder. 2 wing nuts are used to tighten the bracket around the cylinder. Order this from the vendors listed on the cylinder stand options attachment (scroll down). We do NOT recommend the type that has a strap, which must be pulled tight to secure the cylinder because this is not secure enough.  EHS has sample stands that can be borrowed for a few days to check if this option will work. We do NOT recommend stands that are very low and have a very small footprint. These are listed at the end of the cylinder stand options attachment (scroll down).



Some brackets are designed to chain 2-3 cylinders maximum. The bracket needs to be securely attached to the wall to hold the weight of the cylinders: 2 cylinders in parallel or 3 cylinders in a triangle.  Do not use this method to secure more than 3 cylinders because of the hazards described in the first 2 paragraphs on this page. 

Recommended chain link is 1/4 inch in diameter, per Airgas. Chain can be purchased from the Department of Facilities Stockroom (Building E19 1st floor).


Restraints to avoid

The following are not strong enough to hold multiple cylinders and EHS recommends replacing these. If many cylinders are secured with one chain/wire/rope, this is very important.

  • Small diameter chain and chain with flat links (less than 1/4 inch in diameter)
  • Straps that are frayed or are starting to fray 
  • Wire
  • Rope


Rusty caps + no cylinder wrench = gas leak

If a corroded valve is forced open, it may not close properly afterwards and may leak. You may break the valve causing the entire contents of the cylinder to leak. Contact the gas supplier to replace the cylinder if a valve is difficult to operate.


Do not use

  • wrench, hammer, crowbar, etc. to force a valve open or remove a cylinder cap that is stuck (rust, worn threads)
  • WD-40 or other lubricant


Safe way to remove a Cylinder Cap

  • Use a cylinder wrench. (Ordering information is below)
  • Tap very gently on either side of cap to loosen the threads.
  • If you still can’t get the cap off and you don’t have a cylinder wrench, ask John Jordan to come to your lab. 
  • If necessary, contact the supplier to replace the cylinder. Airgas Customer Service 866-718-0685  provide the PO# that is on the tag and/or the barcode # on the cylinder (not the tag)


To order a cylinder wrench from Airgas or Matheson

Airgas part# SGD90003   $27.52  Matheson model TW-5 is a specially constructed Cylinder Hand Wheel Wrench that enables easy opening of cylinder valves that have been fitted with a hand wheel. The design is also suitable for removing difficult cylinder caps.


Return cylinders that are empty, old, unneeded, abandoned or other unusual situations 


Write on the Airgas tag (or tape) EMPTY or Ready for pick up in BIG letters with a marker. Airgas drivers asked us to make it very clear.

Use the webpage to request that Airgas picks up cylinder(s). Airgas coordinates with other vendors to return most types of cylinders.

  • Call the MIT Cryogenic Lab x3-2215 or 3-2250 to pick up their helium (gas) cylinders or cryogenic dewars.
  • If a contractor abandons cylinders, contact the Dept of Facilitiies. 
  • Student Groups can ask SAO to check their purchasing records. 

Alternatives to Non-returnable gas cylinders

Disposing of Non-returnable gas cylinders can be very expensive and time consuming. (These are not the type of cylinder that are rented from Airgas or other vendors.)  In the event that your research requires the use of small compressed gas cylinders, please follow this preferred method for procurement and disposal.

  • Work with Airgas, MIT’s preferred gas vendor, to determine if the gas you need can be purchased in a returnable and refillable cylinder. Airgas can also provide various size cylinders to reduce the potential safety hazards involved in the use of hazardous gases.  They can advise you about other vendors who sell the gases that Airgas doesn’t.
  • Order the smallest returnable or refillable cylinder possible. For example, Airgas’s SAFE-T-CYL program can provide the following gasses in returnable cylinders. (Sulfur Dioxide; Hydrogen Chloride; Ammonia; Chlorine)  Matheson Gas has several options which can be found on
  • Another option is to have a cylinder partially filled with only the amount of gas that you need so you reduce your cost and you reduce the hazard. 


Compressed Gas SOP has more detailed information.

Air Liquide Gas Conversion Calculator and Data on 138 Gases

Air Products Safety information for Cryogenic liquids, CO, CO2, Hydrogen, and a few other gases

Airgas cylinder dimensions and comparison chart of the cylinder sizes for several vendors

Mythbusters video

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