IDLH stands for Immediately Dangerous to Life or health. This term is defined by the National Institute for Occupational Safety and Health, or NIOSH. It is used to describe exposures to airborne contaminants that are extremely dangerous and will likely cause serious health problems or death if someone is exposed to them. This is most commonly used when describing toxic gasses, but it can be other things such as heavy smoke.

If a company has any type of chemical or other solution that could create an environment that is immediately dangerous to life or health, they need to take special precautions to ensure people are safe when working with them. For example, if an employee needs to work with a container of a toxic gas that could be deadly if it escapes into the air, certain precautions must be taken. Most commonly, this would involve wearing some type of personal protection equipment that will allow them to safely breathe even if the air around them is contaminated. For especially toxic substances, it may be necessary to ensure that no air can escape a room where it is used to help prevent the danger from spreading should it be released.

In most cases, the danger has to be immediate and long lasting in order to qualify. In addition, a lack of oxygen in the air typically will not be listed as IDLH. For example, when employees need to work in confined spaces where the oxygen levels may be dangerously low, this will not be a IDLH situation. Of course, those situations still require safety precautions to be taken.

All facilities must know when an area is dangerous or has the potential to become very dangerous. Employees cannot be expected to work in these environments without the proper safety precautions being taken. PPE, including filtered respirators, need to be provided to the employees at the employer’s expense if they need to work in this type of area.

Additional IDLH facts:


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