In addition to the following general guidelines, refer to the Standard Operating Procedure (SOP): EHS-0001 Compressed Gases (certificate required). The SOP includes information about different hazard classes, transporting within campus, etc. For Cryogenics please refer to Cryogen Safety under Chemical – Chemicals: Best Practices and Guidance for Specific Chemicals, Cryogen Safety web course in the MIT Atlas Learning Center, and the Cryogenic Liquids SOP (certificate required).
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. 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 midpoint 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.
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 Linde 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.
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 frayed or ripped strap, replace it with a spare strap that is in good condition or use a chain.
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.
EHS recommends floor stands that have 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.
The recommended chain link is 1/4 inch in diameter, per Linde. The chain can be purchased from the Department of Facilities Stockroom (Building E19 1st floor).
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
If a corroded valve is forced open, it may not close properly afterward 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 another lubricant
Safe way to remove a Cylinder Cap
Use a cylinder wrench. (Ordering information is below)
Tap very gently on either side of the 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. You can contact Linde Customer Service at 1-800-772-4059 . Please 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.
Compressed gas cylinders should not be stored in corridors. Best practices to consider when you cannot store your cylinders in your lab:
To make space, use the Gas Cylinder Summary Report and check if there are any Linde cylinders that can be returned. (This is an MIT Data Warehouse report. The Knowledge Base page provides instructions on how to access the report).
Download the B2P quickcards for instructions on how to request Linde pick up for unneeded cylinder(s) when you don’t need to order cylinders.
Additional information about compressed gas storage and other guidelines can be found in the Standard Operating Procedure (SOP): EHS-0001 Compressed Gases (certificate required).
Return Empty, Old, or Other Cylinders
Write on the Linde tag (or tape) EMPTY or Ready for pick up in big letters with a marker. Linde drivers asked us to make it very clear.
If a cylinder cannot be returned to a vendor, contact EHS Environmental Management Program (EMP) about the cost of disposal, environment@mit.edu.
Call the MIT Cryogenic Lab 617-253-2250 to request a pick-up of their helium (gas) cylinders or cryogenic dewars.
If a contractor abandons cylinders, contact the Department of Facilities.
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 Linde 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 Linde, MIT’s preferred gas vendor, to determine if the gas you need can be purchased in a returnable and refillable cylinder. Linde 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 Linde doesn’t.
Order the smallest returnable or refillable cylinder possible. (Sulfur Dioxide; Hydrogen Chloride; Ammonia; Chlorine) Matheson Gas has several options which can be found on www.mathesongas.com.
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.
In addition to the following general guidelines, refer to the Standard Operating Procedure (SOP): EHS-0001 Compressed Gases (certificate required). The SOP includes information about different hazard classes, transporting within campus, etc. For Cryogenics please refer to Cryogen Safety under Chemical – Chemicals: Best Practices and Guidance for Specific Chemicals, Cryogen Safety web course in the MIT Atlas Learning Center, and the Cryogenic Liquids SOP (certificate required).
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. 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 midpoint 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.
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 Linde 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.
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 frayed or ripped strap, replace it with a spare strap that is in good condition or use a chain.
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.
EHS recommends floor stands that have 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.
The recommended chain link is 1/4 inch in diameter, per Linde. The chain can be purchased from the Department of Facilities Stockroom (Building E19 1st floor).
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
If a corroded valve is forced open, it may not close properly afterward 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 another lubricant
Safe way to remove a Cylinder Cap
Use a cylinder wrench. (Ordering information is below)
Tap very gently on either side of the 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. You can contact Linde Customer Service at 1-800-772-4059 . Please 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.
Compressed gas cylinders should not be stored in corridors. Best practices to consider when you cannot store your cylinders in your lab:
To make space, use the Gas Cylinder Summary Report and check if there are any Linde cylinders that can be returned. (This is an MIT Data Warehouse report. The Knowledge Base page provides instructions on how to access the report).
Download the B2P quickcards for instructions on how to request Linde pick up for unneeded cylinder(s) when you don’t need to order cylinders.
Additional information about compressed gas storage and other guidelines can be found in the Standard Operating Procedure (SOP): EHS-0001 Compressed Gases (certificate required).
Return Empty, Old, or Other Cylinders
Write on the Linde tag (or tape) EMPTY or Ready for pick up in big letters with a marker. Linde drivers asked us to make it very clear.
If a cylinder cannot be returned to a vendor, contact EHS Environmental Management Program (EMP) about the cost of disposal, environment@mit.edu.
Call the MIT Cryogenic Lab 617-253-2250 to request a pick-up of their helium (gas) cylinders or cryogenic dewars.
If a contractor abandons cylinders, contact the Department of Facilities.
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 Linde 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 Linde, MIT’s preferred gas vendor, to determine if the gas you need can be purchased in a returnable and refillable cylinder. Linde 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 Linde doesn’t.
Order the smallest returnable or refillable cylinder possible. (Sulfur Dioxide; Hydrogen Chloride; Ammonia; Chlorine) Matheson Gas has several options which can be found on www.mathesongas.com.
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.