Gas Cylinder Safety Guidance

Introduction:

Boston University (BU) research and teaching laboratories that use compressed gas cylinders must comply with regulations including the Occupational Safety and Health Administration (OSHA), Boston Fire Code, and BU policies and procedures.  These compressed gasses vary in sizes and range from a small lecture bottle to a standard floor size.  Laboratories and users of gas cylinders are responsible for the safe use and must be very familiar with their hazards.  Consult with the Environmental Health and Safety (EHS) if you are setting up or using gas cylinders for the first time or if you have any questions.

Known Hazards:

Compressed gas cylinders present hazards due to their high pressure and the nature of their content.

  • Gases can be inert, toxic, flammable, oxidizing or corrosive. Review the Safety Data Sheets (SDS) before handling.  (Note: SDS are available directly in SciShield to anyone that has BU Kerberos account)
    • Toxic gases create poisonous atmospheres with accidental release.
    • Flammable and oxidizing gases can result in fire or explosion with accidental or uncontrolled release.
    • Inert gases can displace air rapidly creating an oxygen-deficient atmosphere.
    • Work with EHS on the safety, handling, storage, and transport of particularly hazardous gases and follow any relevant SOP specific to the gas.
  • All gas cylinders pose a physical hazard due to the high pressures of the gas(es) inside.
    • If the cylinder’s structure is compromised, it can explode or act as a “rocket”.
    • A falling cylinder can cause physical injury.
    • Note: Cryogenic cylinders can cause and injury to frostbite if mishandled.
Roles and Responsibilities:

Laboratories are responsible for maintaining continual good working order of their gas cylinders.

  • Report any safety issue to EHS and notify and request assistance from Facilities regarding conditions needed to address appropriate restraint.
  • Follow appropriate procedure when the gas sensor goes into alarm and call to notify EHS.
  • Certain gas cylinders are required to be equipped with sensors or placed in a ventilated gas cabinet. Laboratories must contact EHS when these sensors are not working properly.
  • Gas sensors are required to be calibrated annually. EHS manages and funds for the cost of each annual calibration through an approved vendor.  The laboratory is responsible for the cost of any repair or replacement of parts.
Safe Handling:
  • Storage
    • Gas cylinders must be stored in well-ventilated areas. Do not place them in closets that are not designed for their storage.  They must not be stored in corridors, stairways, or other egress paths.
    • Storage where flammable gas is stored must have an appropriate fire extinguisher.
    • Group and store compressed gases based on their hazard classes. Do not place near sources of ignition, near combustibles, or near corrosives. Certain hazardous gases require storage in gas cabinet or fume hood.
    • All cylinders must have valve protection cap in place when in storage
    • If your lab is equipped with a gas sensor or gas cabinet, review its operating parameters. Know your procedures when sensor is in alarm.
    • Empty cylinders must not be stored in hallways or abandoned!

 

  • Securing
    • Cylinders must be secured in an upright position at all times.
    • Secure cylinders with a chain or belt against the wall to prevent from falling over. Submit a service request to Facilities to install wall brackets .  The mount or bracket must be anchored securely to wall studs to ensure that they can hold the weight of the cylinders.  Placement of the strap or chain must be near the top 1/3 of the cylinder (below shoulder).  Periodically inspect straps for damage and immediately replace if damaged.
    • A cylinder bench and table mount bracket may be used. Ensure that the bracket is mounted firmly to a table that is secured to floor.

     

    • Transportation              
      • Gas cylinder vendors are the best resource for transportation of tanks to a designated room and are contracted with BU for the removal of empty or unwanted tanks.
      • Avoid moving cylinders between buildings or between floors within a building. If moving cylinders between floors in a building cannot be avoided, they must be transported using appropriate cylinder dollies on the freight elevator.
      • Examine cylinder for any signs of damage prior to transport.
      • Compressed gas cylinders must be transported with safety caps in place.
      • Firmly secure the cylinder and move with a suitable hand truck or dolly that is also equipped with a chain or strap. Use appropriate equipment, when a cylinder is equipped with lifting attachments from manufacturer.
      • DO NOT roll or allow cylinders to bump violently against another.
      • Gas regulators must be removed and the valve cover replaced before transport.

     

    • Personal Protective Equipment (PPE)
      • Eye protection must always be worn when working with a gas cylinder. A face shield is required when using cryogenic tanks.
      • Foot protection is required when transporting a cylinder.
      • Use cryogenic gloves to protect from frostbite when dispensing cryogenic liquids. Use chemical resistant gloves with corrosive cylinders. Wear a FR lab coat when working with flammable and/or oxidizing gas cylinders.
    • Handling and Use
      • Adequate ventilation is required.
      • Upon arrival, inspect the tank for any issues as corrosion, denting or leaking. Return all questionable cylinders to supplier immediately.
      • Never use a damaged cylinder.
      • Only use regulators, valves, hoses and other auxiliary equipment that are designed for the pressure and contents contained in the cylinder.
      • Perform a leak test or line test after adjusting fittings and/or changing cylinder using a commercially-prepared liquid leak detector (i.e., “Snoop”), especially the joint between cylinder and regulator/manifold and line terminus.
      • Note: Do not use regulators of unknown history. Do not build, modify of use adaptors on gas regulators
      • Regulation is 20 feet minimum between oxidizers and flammable gases or combustible material.
      • Never discharge the contents of a gas cylinder towards a person.
      • Only use non-sparking tools when working with flammable or explosive compressed gases

     

    • Labeling
      • Gas cylinder must be clearly labeled identifying the tank’s contents.
      • The cylinder must be labeled either Full, In Use, or Empty at all times
    References:
    • OSHA 1910.253(b)(2)(ii)
    • Compressed Gas Association (CGA) General Requirements OAR 437-002-2101