Why is this article posted in the Permit-Required Confined Space section of the website? Because there seem to be a large number of safety professionals that are under the impression that ANY occupational hazard can turn a confined space into a Permit-Required Confined Space. Noise is a recognized occupational hazard – I think we can all agree on this; however, noise is NOT a hazard that would turn a confined space into a Permit-Required Confined Space (PRCS). As I have pointed out before, BOTH the GI and Construction standards on Confined Spaces have a “disclaimer” regarding atmospheric concentrations of any substance for which a dose or a PEL is published.
BEFORE you send me hate mail and claim I do not care about workers, let me once again make this clear – NOISE IS A HAZARD which we MUST protect our employees from. But this hazard is managed via our Hearing Conservation Program REGARDLESS of where the exposure occurs. So just because we need hearing protection because of the grinding inside the space is causing our exposure to exceed 90 dBA, this hazard would NOT make the space a Permit-Required Confined Space. We MUST manage this exposure in the same way we would manage it if we were grinding in a small workspace and our exposure would exceed the 90 dBA
In no way did OSHA ever intend that ANY, or ALL, OCCUPATIONAL HAZARDS would make a CS a PRCS and they have said this over and over for decades. Both standards make it clear that for a “hazard” to be one that would make a CS a PRCS, that hazard MUST impact the entrant in such a way that the hazard would cause death, incapacitation, impairment of ability to self-rescue, injury, or acute illness due to its health effects, of which NOISE does not meet these criteria. And yes, I am aware of the police and military weaponizing noise frequencies – but seriously folks, that is NOT an occupational exposure that 99.99% of workers are being exposed to in the workplace. So here is what OSHA has said about noise and PRCSs…
1910.146
(4) Atmospheric concentration of any substance for which a dose or a permissible exposure limit is published in Subpart G, Occupational Health and Environmental Control, or in Subpart Z, Toxic and Hazardous Substances, of this Part and which could result in employee exposure in excess of its dose or permissible exposure limit;
NOTE: An atmospheric concentration of any substance that is not capable of causing death, incapacitation, impairment of ability to self-rescue, injury, or acute illness due to its health effects is not covered by this provision.21926.1203
4. Atmospheric concentration of any substance for which a dose or a permissible exposure limit is published in subpart D of this part (Occupational Health and Environmental Control), or in subpart Z of this part (Toxic and Hazardous Substances), and which could result in employee exposure in excess of its dose or permissible exposure limit;
Note to paragraph (4) of the definition of “Hazardous atmosphere”. An atmospheric concentration of any substance that is not capable of causing death, incapacitation, impairment of ability to self-rescue, injury, or acute illness due to its health effects is not covered by this definition.
More recently, OSHA stated in their Confined Spaces in Construction – Frequently Asked Questions:
62. OSHA has identified “noise” as a potential physical hazard. What noise level must be reached in order to constitute a physical hazard such that the permit-required confined space requirements apply?
There is no specific threshold noise level that must be reached in order for noise to constitute a physical hazard triggering the permit-required confined space requirements. However, the noise must be so extreme that it could impede an entrant’s ability to safely exit the space without assistance. In most instances, noise levels below the eight-hour TWA permissible exposure limit for noise in construction of 90 dBA would not constitute a physical hazard triggering the permit-required confined space requirements.
63. If engineering and administrative controls cannot be implemented in a residential homebuilding project to address potential noise exposures, is it acceptable for a residential home builder to rely on personal protective equipment to address noise exposures for purposes of the Standard?
Yes. A residential home builder may rely on personal protective equipment to address a noise hazard for purposes of complying with the Standard so long as the personal protective equipment itself does not serve to impede the ability of an entrant to safely exit the space without assistance.
From the 1910.146 Preamble: (emphasis by me)
The permit space standard addresses hazards, such as asphyxiation,explosion, and engulfment, that are immediately dangerous to life or health, not the longer term, less obvious hazards subject to section 6(b)(5). The definition of immediately dangerous to life or health in paragraph (b) of the final rule covers conditions that pose immediate or delayed threats to life, would cause irreversible adverse health effects or would interfere with an individual’s ability to escape unaided from a permit space. The definition contemplates that any delayed health effects would arise within 72 hours of exposure to a permit space hazard. Accordingly, the mention of delayed effects simply reflects OSHA’s recognition that some acute health effects may not manifest themselves at the very same time as the permit space incidents which trigger them. While some of the materials, particularly the air contaminants, that have been detected in permit spaces could also have long-term adverse effects on employees, those long-term effects are not addressed by the permit space standard.
