Compressed gas cylinders may be used in laboratories and other locations at NIH for various applications and processes. They can be inert, toxic, corrosive, oxidizer, and flammable depending on the nature of the chemical. Nitrogen, argon, helium, oxygen, and carbon dioxide are the most used compressed gases at NIH.
When not handled properly, compressed gas cylinders can pose potential health and safety hazards such as fire/explosion, toxic exposures, and oxygen displacement.
Safety Guidelines on Cryogens and Compressed
Gases
- Labeling: Cylinders must be clearly labeled with the name of the gas and hazard warning (e.g., toxic, flammable, corrosive, etc.). Additionally, cylinders should be labeled adequately when empty or full.
- Segregation/Separation: Oxygen and other oxidizers must be separated from flammable gases and combustible materials by 20 feet or with a non-combustible barrier. Full cylinders should be separated from empty cylinders.
- Securing: Cylinders should always be secured in an upright position except while hosted or carried. Secure cylinders with strap/chain connected to a wall bracket or fixed surfaces. A maximum of two cylinders can be secured in one strap or chain. Another option is to use secured cylinder stands.
- Transportation: Use a hand truck or cart designed to move cylinders. Cylinders must be closed, capped, and secured to the cart before their transportation.
- Storage: Cylinders must be stored in a well-ventilated area (e.g., no confined spaces or cold rooms).
- Signage: Prominently post appropriate hazard warning signage at the storage location
- Monitoring: Some of the locations using/handling compressed gases may require oxygen monitoring, or other chemical-specific monitoring to prevent exposure/asphyxiation. Consult DS for guidance.
Compressed Gas Cylinder Signage
Flammable Gas Sign
Corrosive Gas Sign
Toxic Gas Sign
Compressed Gas Safety Sign
Procedures using Carbon Dioxide (CO2) or Dry Ice
Carbon Dioxide (CO2) is a colorless and odorless gas. It can also be found in liquid or solid form (e.g., Dry Ice). CO2 can deplete oxygen, which makes it hazardous and can cause asphyxiation. All CO2 and dry ice procedures must be performed in a well-ventilated area. Never use or store CO2 and dry ice in confined spaces, walk-in refrigerators, or cold rooms. For more information refer to Carbon Dioxide Safety Fact Sheet.
Compressed Gas Leak and Emergency Plan
Compressed Gas Leak: Flammable, Toxic or Corrosive
If there is a leak of a flammable, toxic, or corrosive gas outside of a ventilated enclosure that will contain the gas, immediately activate the building fire alarm system and evacuate the building. Call the Fire Department Immediately.
- Bethesda: call the NIH Fire Department at 301-496-2372 (301-496-9911 from a cell phone).
- All other locations: call 911.
Compressed Gas Leak: Inert Gas
If closing the cylinder valve cannot stop the leak and it is an inert gas (e.g., nitrogen, argon, etc.), evacuate the area.
- Call the NIH Fire Department at 301-496-2372 for Bethesda Campus or 911 for satellite locations.
- Restrict access to the area.
- Contact your supplier and return all problem cylinders.
Emergency Plan
If your area is using compressed gas, plans should be developed to address both minor and major leaks before using the gas. This plan should consider the nature of the gases being handled, based on their chemical and physical properties.
At a minimum, the plan should specify the following:
- Alarm System (if needed) & Evacuation Procedure.
- Response Personnel.
- Emergency Equipment.
- Containment or disposal methods.
Before use, consult DS for additional safety procedures and recommended methods for responding to leaks and emergencies. Emergency plans for toxic and flammable gases must have approval from DS.
