Workers and the public often interact with commercial gases and may not even know it.  It is the responsibility of an owner of a facility or commercial building to detect and then protect any workers or individuals who may come into contact with certain gases that have been classified as hazardous.  Regulations and standards are set by both OSHA (Occupational Safety and Health Administration – a federal agency) and ACGIH (A member-based organization that advances occupational and environmental health).

According to the ACGIH, highly toxic gases include:

  • Gases that have a median Lethal Concentration (LC50) in air of 200 parts per million by volume or less of gas or vapor when administered by continuous inhalation for one hour (or less if death occurs within one hour) to albino rats weighing between 200 or 300 grams each.
  • A Threshold Limit Value (TLVs®) as established by ACGIH or a Permissible Exposure Level as established by OSHA, less than or equal to one part per million.
  • Designated as a “Poison A” by the DOT, and defined as poisonous gases or liquids of such nature that a very small amount of the gas, or vapor of the liquid, mixed with air is dangerous to life (49CFR173.326).In addition, ACGIH has set guidelines.

As the second bullet points out, TLV is an important way to measure potential harm from any exposure to known hazardous gases.  The TLVs were developed as a guideline to assist in the control of health hazards.

An important way to monitor these gases is the use of gas detectors that can identify TLV levels of gas.  If a gas exceeds the threshold amount, the detector will set off an alarm so that workers and any other individuals in the vicinity can quickly exit to a safe location that is far from any dangers associated with the gases.

Some of the gases that detectors can alert workers to are:  hydrides (arsine and phosphine) and mineral acids (hydrogen fluoride, hydrogen chloride, etc.).    Some of these gases can quickly send people to the hospital with respiratory issues, skin rashes, and some may even cause death.  When any hazardous gases are present, it is extremely important to have detectors in place to sound the alarm when an accidental release of the gases occurs.

Fortunately, there are requirements that all hazardous gases and locations that are dealing with hazardous gases maintain a Material Safety Data Sheet (MSDS).  These safety data sheet provide critical information for workers and EMT personnel so that they can instantly know how to handle certain substances in a safe manner.  The sheets include information about the gases’ physical properties (e.g., melting point, boiling point, flash point, etc.), overall toxicity, health effects, first aid that can be performed, reactivity, storage, disposal methods, protective equipment for handling, and spill-handling procedures.