Choosing a respirator is a complicated matter. Experienced safety professionals or occupational hygienists, who are familiar with the actual workplace environment, are the staff who should select the proper respirator. They can choose a suitable respirator only after they have evaluated all relevant factors. This includes considering the limitations of each class of respirator. Before the proper respirator can be selected for a job, be sure you have already:

  • Identified the respiratory hazard.
  • Evaluated the hazard.
  • Considered whether engineering controls are feasible.
  • There are too many types of situations to cover them all fully here. However, the following questions represent part of “decision logic” that a safety professional or occupational hygienist can use when selecting a respirator:
  • Is it to be used in firefighting or emergencies?
  • Is it to be used in oxygen-deficient atmospheres (less than 18% oxygen in air; some jurisdictions say below 19.5%)?
  • What is the nature of the hazard (chemical properties, concentration in the air, warning properties)?
  • Is the airborne contaminant a gas, vapor or particulate (mist, dust or fume)?
  • Are the airborne levels below or above the exposure limit, or are they above levels that could be immediately dangerous to life or health?
  • What are the health effects of the airborne contaminant (carcinogenic, potentially lethal, irritating to eyes, absorbed through the skin)?
  • What are the characteristics of the operation or the process (e.g., hot temperature, confined space)?
  • What activities will the worker be doing while wearing the respirator (e.g., strenuous work)?
  • How long will the worker need to wear the respirator?
  • Does the selected respirator fit the worker properly?
  • Where is the nearest safe area that has respirable air?

Source from Canadian Centre for Occupational Health & Safety. http://www.ccohs.ca/oshanswers/prevention/ppe/respslct.html