0.42 Fibers per cc and a Crew That Wants to Keep the Half-Masks
During a three-week glove-bag removal of 300 linear feet of friable pipe insulation in a hospital mechanical room, personal air samples come back at 0.42 f/cc 8-hour TWA for the insulator and 0.09 f/cc for the helper. The employer currently issues half-mask negative-pressure air-purifying respirators with P100 filters. On day two: one worker has a full beard and says the half-mask 'passes fine if I tighten it'; one wears prescription glasses and wants a full-facepiece; one asks to switch to a loose-fitting PAPR hood so he can skip the fit test; and one reports adult-onset asthma but says he 'always wears his respirator at home.' The supervisor wants to keep the half-masks, arguing that the glove bags are an engineering control and that the average of the two samples is below 0.1 f/cc.
1. What is the minimum acceptable respiratory protection for 0.42 f/cc and for 0.09 f/cc, and is the supervisor's averaging argument valid?
Read the worked answer
Selection is per employee, from the exposure level, using the respirator selection table in 29 CFR 1926.1101(h)(3):
- at or below 0.2 f/cc: half-mask APR is the minimum;
- at or below 1.0 f/cc: full-facepiece APR or half-mask PAPR;
- at or below 10 f/cc: full-facepiece PAPR or supplied air with continuous flow;
- above 10 f/cc or unknown: pressure-demand SCBA or supplied air with escape provision.
So the insulator at 0.42 f/cc cannot lawfully wear a half-mask negative-pressure respirator; he needs at least a full-facepiece APR or a half-mask PAPR. The helper at 0.09 f/cc is within the half-mask band.
Averaging is invalid. Each employee's own 8-hour TWA is compared to the PEL and to the table. You cannot blend two people's samples, and you cannot argue the control 'counts' as protection - respirator selection is driven by measured exposure, not by intent.
Second issue. 0.42 f/cc is above the 0.1 f/cc 8-hour PEL and the results must push engineering and work-practice improvements (better bag sealing, reduced bag volume, wetting, local exhaust, sequenced work), not just a respirator upgrade. Confirm the 1.0 f/cc 30-minute excursion limit is not being exceeded, extend sampling to the whole crew, and post the regulated area.
2. Address the four individual situations: beard, prescription glasses, loose-fitting PAPR, and asthma.
Read the worked answer
Beard. Hair at the sealing surface makes a tight-fitting facepiece unusable - no amount of tightening creates a seal, and a passed user seal check does not override it. Either he becomes clean-shaven at the seal, or he is issued a loose-fitting PAPR or supplied-air hood.
Glasses. Street glasses cannot be worn under a full-facepiece; the temples break the seal and the lenses fog. Order the facepiece with a corrective spectacle insert, and fit-test with the insert in place. Do not accept 'I'll take them off inside.'
Loose-fitting PAPR. This is a legitimate answer here: no fit test is required for a loose-fitting hood, and its assigned protection factor comfortably covers his exposure. It is not a shortcut around the program - he still needs the medical evaluation, training, and a written program, and the hood must be intact and the blower functioning.
Asthma. He cannot self-clear and the supervisor cannot clear him. A physician or other licensed health care provider must evaluate him using the OSHA questionnaire before fit testing or use, and may clear him with limitations, require a different respirator, or restrict him from respirator use entirely. The employer acts on the written opinion. Note also that a PAPR (positive pressure) is often better tolerated than a negative-pressure mask.
Bottom line. One facepiece model cannot serve this crew. Individual issue plus documented fit testing, or a switch to supplied-air/loose-fitting hoods for the whole job, resolves all four.
3. List the program elements the employer must document for this crew before work resumes.
Read the worked answer
Written respiratory protection program covering selection, medical evaluation, fit testing, use, maintenance, and training, administered by a named program administrator.
Medical evaluation for every respirator user before fit testing or use, with the PLHCP's written opinion and any limitations recorded.
Fit testing before initial use, annually thereafter, and whenever a different facepiece make, model, or size is introduced or a facial change (weight change, scarring, dental work) could affect the seal. Records include the test method, the facepiece, and the results.
Daily use controls: user seal check each donning, no facial hair at the seal, no glasses under a full facepiece, and a cartridge/filter change-out schedule for the P100 filters based on breathing resistance, hygiene, and the manufacturer's guidance - not on 'it still smells clean.'
Training and inspection: how to don and doff in the decon sequence, recognize filter loading, and store the respirator clean and dry; respirators provided at no cost.
Tie-in to the asbestos standard: respirators are required for Class I work and until clearance is achieved, but the employer must still show that feasible engineering and work-practice controls are in place. Attach the personal monitoring results, the selection rationale, and the area posting to the project file.