Significant (and Overlooked) Facts About 1926 Subpart AA

October 1, 2015 – When OSHA issued their new “Confined Spaces in Construction” standard (29 CFR 1926, Subpart AA) earlier this year, they announced that there were a “few” key differences in this new rule as compared to their 1910 general industry standard for permit-required confined spaces. And as always when OSHA issues a new standard, I tear it apart and analyze it frontwards and backwards to find the “hidden” things that employers cannot afford to overlook. And there are some doozies hidden within this new confined space in construction regulation! So I thought I’d address one of the most significant (and overlooked) revelations about this new standard in this month’s post to the blog, and then expand on some of the other significant differences about this new standard in future posts to the blog.

Below is how OSHA briefly describes one of the differences in its new construction standard on their website:

“[Includes] more detailed provisions requiring coordinated activities when there are multiple employers at the worksite. This will ensure hazards are not introduced into a confined space by workers performing tasks outside the space. An example would be a generator running near the entrance of a confined space causing a buildup of carbon monoxide within the space.” 

On its surface, this brief explanation of the standard would seem to require all employers on the site to communicate directly with each other regarding hazards that may affect one another when working on or near confined spaces. And that makes sense, because the OSHA Act of 1970 places the responsibility on employers to provide a safe work environment for their workers.

But once you dig into the support information provided by OSHA (e.g.: the preamble to the confined spaces in construction standard and OSHA’s FAQ’s), you see that is not the case at all. The new rule makes the “Controlling Contractor” (whom OSHA defines as “the employer that has overall responsibility for construction at the worksite” – or in other words, the General Contractor) the central point of coordination for information about permit spaces and hazards at the work site

While the host employer (defined by OSHA as “the employer that owns or manages the property where the construction work is taking place”) must provide information it has about permit spaces at the work site to the controlling contractor [per 1926.1203(h)], it is the controlling contractor who must then pass it on to the employers whose employees will enter the spaces (entry employers).  But more importantly, OSHA states in their preamble and in the FAQ’s that the controlling contractor is also responsible for coordinating the activities of other entities working inside and outside of a space so they do not to create hazards in the space, as well as making sure different entry employers working in a space at the same time do not create hazards for one another’s workers.

It is that last part that can get tricky for general contractors (controlling contractors). To show what I mean, read the following three “examples” OSHA inserted into the preamble to this standard:

Example 1 - A controlling contractor is walking the worksite and notices a significant amount of water pooling so that it might enter an underground permit space. The controlling contractor must alert the subcontractor working in that space of the potential for water entering the space or weakening the structure, and must also inform other entities in the area whose activities could foreseeably result in a hazard inside the confined space (e.g., entities whose activities may be contributing to the pooling water, may convey an electric charge through the water into the confined space, or may weaken the structure around the confined space to allow the water to enter the space).

Example 2 - The controlling contractor hires a subcontractor to apply a flammable epoxy coating to the walls of a confined space; the subcontractor does so under a permit program, and then cancels the permit in compliance with this final rule. The controlling contractor must inform subsequent employers entering the space about the application of that epoxy and the procedures used to address hazards in the space.

Example 3 - The controlling contractor hires a welder to weld a new structure inside a fully-enclosed above-ground permit-required confined space. The welder sets up a ventilation system that complies with all applicable OSHA requirements. The controlling contractor also hires a different subcontractor to perform unrelated excavation work 75 yards away from the permit space. The controlling contractor must alert the excavation contractor to the fact that a welder is working in the confined space, that the space has been designated a permit space and must not be entered by any of the excavation contractor's employees, and that the welder is relying on a ventilation system that must not be impacted by the excavation contractor's activities, such as by blocking the ventilation system or by operating heavy machinery, generators, etc. in such a way that their fumes could enter the confined space.

As you can see from these three examples provided by OSHA in their preamble, General Contractors who oversee construction sites with confined spaces have been given a lot of responsibility in this new OSHA confined spaces in construction standard, or at least as it is explained by OSHA in their preamble and FAQ’s; well beyond what I believe was originally envisioned when the OSH Act of 1970 was written by Congress. And the situation is made worse because the scope of what OSHA expects of General Contractors is not clear in the standard itself, and requires affected employers to dig into these support documents to see OSHA’s intent.

So considered yourselves warned, GC’s, and bone up on this new standard, as I foresee an avalanche of OSHA citations about to come down on your heads!

Were you aware of these requirements for “controlling contractors” that appear in the new standard? Had you read the preamble to the standard to discover what OSHA added there, and if so, were you as surprised as I was to see what they say they expect of GC’s??  Do you feel this is above and beyond the scope of a GC’s responsibilities as required by the OSHA Act of 1970, or do you believe it is in line with that Act?  What have you done to prepare for complying with OSHA’s expectations??

If you would like to comment on this topic (and I hope you do) or would like to read comments submitted by others, please click here and fill in the “Comments” box. And last but not least, I would like to encourage you to Share this Blog post with others in your Network who might enjoy reading this information. 



Curtis Chambers is a Certified Safety Professional (CSP) and holds a Master of Science degree in Occupational Safety and Health. He has held numerous leadership positions managing and evaluating health and safety programs and providing training on workplace safety and health topics at various public organizations and private corporations. Mr. Chambers is currently the President of OSHA Training Services Inc. Visit their website at  
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