According to OSHA 1910.134, Personal Protective Equipment, when engineering controls are neither feasible, available nor effective in preventing the breathing of harmful dusts, fumes, gases, vapors, sprays, etc., then appropriate respirators must be worn. The regulation goes on to say that the employer must provide each employee with respirators that are suitable and applicable for the purpose intended. There are respirators for virtually every type of operation. For example there are Air-Purifying -Atmosphere-Supplying; Escape Only Respirators to name just a few.
Wearing a respirator does not automatically mean that an employee is completely safe from the atmospheric conditions he or she is working in. The maximum use concentration (MUC) is determined by multiplying the assigned protection factor specified for a respirator by the required OSHA permissible exposure limit.
Each employer is required to both develop and implement a written respiratory protection program which will include worksite-specific procedures. The program has to be flexible so that if environmental conditions change over time, the procedures involved to meet the new conditions will able to be implemented immediately. Proper procedures generally include: physical examinations of all employees prior to use; close inspection of the respirators to be used; scheduled cleaning, canister or cartridge changes, disinfecting, repairing, respirator end o life indicator, etc. of all respirators, training and retraining of employees on proper use and reevaluation of the entire program.
Respirators that are considered necessary because the environment poses a condition that is “Immediately Dangerous To Life or Health” (IDLH) must meet the requirements of The National Institute for Occupational Health and Safety (NIOSH.) When an IDLH condition does not exist, an employer must still provide a respirator that will adequately protect the health of the employee(s) for the current environmental condition an operation is taking place in.
When respirators are in use, at least one employee must be located outside of the IDLH area and that person must be trained and equipped to provide emergency rescue if necessary. This includes appropriate retrieval equipment.