Our Interpretation: OSHA’s Confined Spaces Standard

Consultant Rich Fairfax focuses his attention on OSHA’s confined spaces standard, offering his advice on several issues raised by members.

Richard Fairfax
July 18, 2019

Question: Our situation pertains to a permit required confined space (PRCS) that is reclassified as a non-permit space when entered under lockout/tagout (LOTO) conditions. The equipment (a crusher) is entered daily for a cleaning task. I was informed recently by a Cal/OSHA inspector that the reclassification documentation must be completed each time the crusher is entered under the same LOTO conditions for the same cleaning task. Our current policy is to complete the documentation for reclassification annually so long as additional hazards are not introduced and all hazards remain eliminated during the entry and the task is not changed, any of which would require a re-evaluation. Do you think the inspector has provided me with the proper application of the standard? I am curious whether you are aware if our practice is out of sync with how other employers have handled reclassification?

Answer: First, I do find myself in agreement with the Cal/OSHA inspector in his/her opinion/response. In this situation we are bringing in two separate OSHA standards. Certainly the LOTO standard requires LOTO whenever employees are exposed or potentially exposed to any release of energy and OSHA defines releases of energy pretty broadly. Under OSHA’s confined space standard, I found the standard (no big surprise anymore) less than clear on whether the reclassification has to be done each time the space is entered or if it could be done annuall

1910.146(c)(7)(i) is the general requirement for reclassifying a PRCS and ensures that no hazard, whether physical or atmospheric, exist in the space.

Other key OSHA standards include:

1910.146(c)(7)(ii): If it is necessary to enter the permit space to eliminate hazards, such entry shall be performed under paragraphs (d) through (k) of this section. If testing and inspection during that entry demonstrate that the hazards within the permit space have been eliminated, the permit space may be reclassified as a non-permit confined space for as long as the hazards remain eliminated.

NOTE: Control of atmospheric hazards through forced air ventilation does not constitute elimination of the hazards. Paragraph (c)(5) covers permit space entry where the employer can demonstrate that forced air ventilation alone will control all hazards in the space.

1910.146(c)(7)(iii): The employer shall document the basis for determining that all hazards in a permit space have been eliminated, through a certification that contains the date, the location of the space, and the signature of the person making the determination. The certification shall be made available to each employee entering the space or to that employee’s authorized representative.

Although I don’t find these two sections of the standard to be very clear, I can see how OSHA would read them to mean that documentation for reclassification has to be done on each entry. And from a purely health and safety perspective I can see OSHA reading the standard in that way.

It is possible that you could document your process in writing including the checks and double checks enough times to establish that you have a LOTO program that, upon prep prior to entering lock out, is implemented, which then declassifies the space. And then you would need to establish a pattern of periodic checks to ensure your process and procedure is in place and working. Then … if OSHA were to inspect and challenge you on it, you have data and information to support your position. But … from a personal point of view, I think it would be far better, and would ensure compliance, to certify the space as safe each time one must enter, even if it is on a daily basis.

Fairfax also examined two proposed scenarios to interpret OSHA’s confined spaces standard. The two scenarios, presented by ORCHSE members, are as follows:

Scenario 1:

Two weeks ago, personnel were reaching into a vessel installing hearer coils and the area was posted as a permit required confined space (PRCS). When the specific evolution was complete, the permit was removed, and the signage returned to the control room. No additional work has been performed and I do not know when work will resume. While walking through our site, the internal auditor asked the area manager why the Confined Space posting was not up as the vessel was still open. The area manager stated it was an oversight and asked me to intercede.

We explained that no work was currently going on in/around the tank and the team would obviously re-evaluate the space, post, and develop a permit to control the work. We all agreed this was the correct approach. However, we differ in our opinions regarding the requirement to keep the vessel posted (even when no work is being performed and vessel is open). I explained that I believe it is a best management practice to maintain postings on open and identified spaces. However, I referenced 29 CFR 1910.146(c)(1) as it requires employers to “…evaluate the workplace to determine if any space(s) are permit-required confined spaces.” Once such spaces are identified, employees must be informed about the existence of the space(s) and hazards they pose.  29 CFR 1910.146(c)(2) does not require confined spaces to be posted continually, provided personnel are trained on recognizing confined spaces, and the location of confined spaces and hazards they present are described. Requirements change when the space is evaluated to support a specific task where personnel will make entry. 


Unfortunately, OSHA, in trying to give an employer compliance options, has confused the issue. Under 29 CFR 1910.146(c)(2), the employer has two options on a PRCS. The first is to post the space as a PRCS with a danger warning. Most people I talk to have interpreted this to require that a sign always be posted regardless of whether the space is in use. This same standard then gives a second option: the employer can inform the employees by any other equally effective means, of the existence and location of a permit space as well as the danger it poses. (This section of the standard also has a note advising what the posted sign should state.)

The route you have gone makes this hard because it requires a lot of extra work and documentation on your part so you can explain and justify to an OSHA inspector that what you have in place is as effective as posting a sign. (For the record, I thought your actions seemed reasonable except I would want to keep the opening to the confined space closed unless there is an operation requiring entry.)

Other potential issues with your employee notification approach is that you would have to make sure that any new employees are trained and advised on the locations and types of PRCSs you have on site. This approach can be difficult, as I can tell you that most OSHA compliance officers are of the opinion that if it is a PRCS there must then be a sign posted. If you think you have it all covered through your training and procedures, and that employees know and understand what and where the confined spaces are, and that you can explain to an OSHA compliance officer why you are in compliance and do not need to actually post the space, then I believe you are good. I would make sure you have all this covered in writing, so if a compliance officer asks you can provide written documentation on your procedure and process. In my opinion, I would just keep the signage in place ‒ that way you know you have it covered and you are clearly in compliance, with no second guessing. And I would make sure that the opening closed off when not being used. I have done fatality investigations where the company left a PRCS opening open, there was no signage (this was prior to OSHA’s confined space standard), and someone, totally unexpectedly, climbed into it and died.  Hence, I would add that, in my opinion, a continually posted sign is a better practice. 

Scenario 2:

We have a melt tank that is primarily located below the ground. A small opening, roughly 18 inches in diameter, is kept open so workers can intermittently pour product into it when a bag is accidentally torn. The process of pouring material into the tank is covered by procedure and personnel do not breach the plane of the vessel. While it is a good idea to post it as a permanent confined space, it isn’t necessarily required, provided personnel understand it is a confined space, have received confined space recognition training, understand the hazards it poses, and know that they may not breach the vessel’s plane.


While you did not say in describing the scenario, I am assuming the 18-inch opening is either securely covered or has an adequate guard rail around it as would be required under OSHA’s Walking and Working Surfaces Standard since the opening is roughly at ground level. As to the signage issue, I would fall back on my response to the first scenario. I think it is easier and probably better to just post it as a PRCS. But if you believe you have it covered otherwise than as stated in the standard under (c)(2) you would be good.

Richard Fairfax

Richard Fairfax is a subject matter expert and principal consultant for NSC. Prior to that, he was director of enforcement programs and deputy assistant secretary for OSHA.

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