While the ancient Greek philosopher Socrates didn’t have the benefit of modern technology, he definitely had the right idea: the beginning of wisdom, he said, is the definition of terms. And it’s still true—even in occupations that don’t require a philosophy degree!

It’s important for all workers to understand the terminology found in relevant safety standards, especially when they’re working in environments that may be particularly dangerous, like confined spaces. Why? Because you can’t apply what you don’t understand.

This isn’t always as simple as it sounds. Terms are often defined a bit differently depending on which standard, or subpart of a standard, you’re looking at. Furthermore, standards change on a regular basis. But—rather than ignoring variations or letting revisions frustrate you—find the time to periodically review and compare definitions in each standard. Doing so will deepen your understanding of confined space safety best practices.

Take, for example, the term hazardous atmosphere. The newly revised ANSI Z117.1 Standard broadly refers to the possible hazards as “oxygen deficiency or enrichment; flammability or explosivity by gas, vapor, dust; or toxicity.” OSHA 1926.1202, however, includes specifics for these general categories, e.g., ANSI’s “flammability… by gas [or] vapor” becomes OSHA’s “flammable gas, vapor or mist in excess of 10% LFL.” Here we have a concrete definition of a hazard that can be measured and monitored. In this case, OSHA 1926.1202—and its counterpart OSHA 1910.146 (b)—more precisely and actionably explain hazardous atmosphere.

Another expression more fully defined in the OSHA 1926 Standard is serious physical damage. ANSI Z117.1’s explanation of a similar phrase is not especially detailed: “Serious Hazards. Conditions which may cause death, temporary or permanent impairment, functional disorder or an inability to exit the space.” OSHA 1926 expands ANSI’s explanation to include “an impairment or illness in which a body part is made functionally useless… and includes loss of consciousness.” Such a condition “would usually require treatment by a physician or other licensed health-care professional.” It’s important to note that OSHA 1910.146 (b) does not define serious hazards at all; therefore, those seeking to categorize potential injuries at any worksite—in construction or general industry—will appreciate the specifics outlined in OSHA 1926.1202.

These are just two examples of comparing and contrasting definitions found in the three confined spaces standards.