Safety Tips For Using Cryogenic Materials

Cryogenic gases – including argon, nitrogen, oxygen, helium and carbon dioxide – are pretty cool – about -238 Fahrenheit (-150 Celsius), to be exact. They’re so cool, in fact, that they’re used for doing everything from removing tumors to launching rockets.

Given the extremely low temperatures of cryogenic liquids, there are several general precautions and best practices that must be followed to keep handlers safe. Consider these guidelines for handling cryogenic gases, courtesy of the Yale University office of Environmental Healthy & Safety.

Potential Hazards

The use of and handling of cryogenic materials pose the following potential hazards:

• Extreme Cold – Direct contact with cryogenic liquid, vapor or non-insulated parts of equipment used to transfer cryogens will immediately freeze body tissue and effect the skin in ways similar to a thermal burn. Unprotected skin can also adhere to cryogen cooled metal surfaces and tear when pulled away.
• Asphyxiation – Cryogens expand extremely quickly when converted from a liquid to a gas. It is possible that enough oxygen is displaced during this expansion for asphyxiation to occur.
• Structural embrittlement – The extreme cold temperatures of cryogenic liquids and gases can cause structural embrittlement, weakening the integrity of carbon steel, zinc, plastic and rubber. Unanticipated structural failure can pose a severe physical hazard.
• High pressure – During vaporization, the volume of cryogenic gas increases rapidly and could cause an explosion if the expansion occurs in an in an enclosed space such as an unvented container or plugged venting tube.

Precautions And Controls

• Personal Protective Equipment – Personal protective equipment (PPE) must be worn whenever handling cryogens. In addition to the standard laboratory apparel of closed-toe, solid top shoes and long pants without cuffs, insulated cryogenic gloves must also be worn. A face shield is also required when handling cryogens under pressure such as dispensing from a pressurized container into an open dewar.
• Ventilation – Cryogens must be used and stored in areas with adequate ventilation to prevent creating an oxygen deficient atmosphere. There are scenarios in which even a release of gas from a lab-size dewar could cause the oxygen levels of the room to become dangerously low. Contact us to learn more about ventilation for use with cryogenic gases.
• Oxygen Monitors – There are circumstances during which cryogens may be used or stored in areas where the ventilation is inadequate or recirculated. In these situations, either fixed or personal oxygen monitors may be necessary. Contact us to learn more.
• Safe Handling – In addition to the precautions and controls listed above, the following safety measures should also be taken:
  • Avoid contact with uninsulated cryogenic piping, systems and reservoirs.
  • Do not store cryogenic liquids in walk-in cold rooms.
  • Never store a cryogen in a sealed container at a temperature above the boiling point of the cryogen as the pressure resulting from the production of gas can lead to an explosion.
  • Do not tamper with pressure relief devices on equipment designed for cryogen use/storage. Constant/non-stop venting is a sign of a broken valve.
  • Periodically inspect equipment and remove ice and frost blockages from openings to prevent over pressurization (LN2 vents will always build frost and ice on filling).
  • Never pour a cryogen on tiled or laminated surfaces as this may severely damage the surface.

Personal Exposures And Spills

• Exposure – If a cryogen is spilled on skin or there is contact with cryogenic material, immediate medical attention is necessary.
  • Remove PPE and clothing that may contain cryogen material quickly upon contact.
  • Material that may be frozen to the skin should be left in place and removed only by medical professionals.
  • For minor burns, consult your doctor; for more serious exposures, call 911 immediately.
• Spills – Large spills of cryogens, or smaller spills in confined spaces or areas without adequate ventilation, can lead to an oxygen deficient atmosphere. In these situations, the area must be immediately evacuated.

James Oxygen Is Your Cryogenic Gas Specialist In Western NC

James Oxygen & Supply can supply the product you need and the services to support it safely. From bulk cryogenic gas delivery to installing and setting up of your cryogenic gas system, we’ll get the job done quickly, safely, and correctly. We’ll even provide on-site safety training for your employees to prevent problems down the road.

Count on James Oxygen & Supply for your cryogenic gas needs. Contact us today to learn more about what we can do for you!