Want to Really Understand an OSHA Standard? Read the Preamble!

When OSHA Compliance issues a new or revised health or safety standard, inevitably questions will arise. Perhaps OSHA did not define a key term used in the standard, or maybe they used some subjective language that could be open to interpretation. Issues such as these can make it difficult for employers to implement the new regulation. However, questions can often be answered by simply taking the time to read the Preamble to the Final Rule printed in the Federal Register when OSHA publishes a new standard, most specifically the section titled “Summary and Explanation of the Standard.”

So what is this Preamble I am talking about? When OSHA promulgates a new or revised health or safety standard, they go through a long process by where they draft the proposed standard, publish it in the Federal Register as a Proposed Rule, and allow a period of time for stakeholders to comment on the proposed rule. After considering all the input provided by the stakeholders, OSHA will tweak the draft standard and then publish it in the Federal Register as a Final Rule, along with a wealth of other information gathered during the process. As a side note, this process usually takes 10+ years to complete, and in the end OSHA may actually abandon the proposed standard.

In the section of the Federal Register titled “Summary and Explanation of the Standard”, OSHA will break the proposed draft standard down paragraph by paragraph, and include the many comments, questions, and concerns expressed by the stakeholders about each paragraph. This process reveals many ambiguous areas contained within the originally drafted standard, and OSHA’s subsequent explanation or rebuttal provided within this section of the Preamble often provides valuable insight into OSHA’s intent when they created the standard.

Here are a couple of examples of what I am talking about, both originating from OSHA’s permit-required confined space entry standards for general industry:

• Paragraph 1910.146(b) defines one of the three criteria of a “confined space” as "the space is large enough and so configured that an employee can bodily enter and perform assigned work". Many people are confused by the term “bodily enter”; it is not defined in the OSHA standard, and some people think it means that if the space is large enough and configured so an employee could place any part of their body inside the space, it would be a confined space. But in the Preamble to the Final Rule for the Permit-required Confined Space Entry Standard, the section that discusses this particular term explains that the standard is intended to cover only spaces that were large enough for the entire body of an employee to enter. So now we have a clear definition of the term “bodily enter” as it applies to this standard.


•  Paragraph 1910.146(c)(5)(i) allows the employer to utilize “alternate entry procedures” to enter certain permit-required confined spaces where they are able to demonstrate that the only hazard posed by the permit space is an actual or potential hazardous atmosphere, as long as the employer can demonstrate that continuous forced-air ventilation alone is sufficient to maintain the permit space “safe for entry”. Unfortunately, the OSHA standard does not quantify what OSHA considers to be “safe for entry”. But in the section of the Preamble to the Final Rule that discusses paragraph(c)(5), OSHA explains that employers may use “a guideline of 50 percent of the level of flammable or toxic substances that would constitute a hazardous atmosphere in making the determination”. So now we know that using forced air ventilation to maintain flammable gas at no more than 5% of its LEL (half of the OSHA limit for a “hazardous atmosphere when considering flammable gas) would be considered “safe for entry” when utilizing these alternate entry procedures.

Sure, many issues such as these are later clarified by OSHA in their letters of interpretations or directives, but those typically are created years after the standard has been published. So why wait? Be in the know from the beginning by reading the Preamble to the Final Rule whenever OSHA publishes a new or revised OSHA standard.

Where can you locate Preambles to Final Rules published by OSHA? Sometimes you can simply “Google” the particular Federal Register you are looking for (e.g.: preamble final rule 1910.146) and sort through the results. Or you can go to www.FederalRegister.gov to search for the document or topic you seek (here is the link for the preamble to the permit-required confined space standard).

Remember, however, that none of this applies to OSHA’s original standards that were issued back in the early ‘70’s, as those standards do not have a preamble. This applies only to those standards that were created or revised since then, such as but not limited to, Lockout/Tagout, Hazard Communication, Bloodborne Pathogens, Forklift Operator Training, Respiratory Protections, Personal Protective Equipment, Steel Erection, & Fall Protection and Prevention. One more important thing to keep in mind is that OSHA does occasionally issue technical corrections to standards through the Federal Register as well, so also search for any related preambles that address updates when researching a particular OSHA standard.

Have you ever found a helpful “nugget” of information that was buried inside the Preamble to a particular OSHA standard that you found especially valuable?  If so, or if you have other related comments about this topic, would you please share your experience with others in the comments section below?