Span of Control - Still a Gray Area, But Getting Clearer

This one has come up a few times recently, so it's worth spelling out clearly. Span of control refers to the practice of allowing an unqualified worker to perform a covered task while being directed and observed by a qualified person. Specifically, 'span of control' is the ratio of how many unqualified workers can be effectively 'directed and observed' by a qualified worker. The term is not formally defined in the PHMSA regulations, but is in industry standards (ASME B31Q, etc.).

The Core Question Operators Keep Asking

How many unqualified workers can one qualified person direct and observe at the same time?

From a regulator's perspective, anything beyond a one-to-one ratio is very difficult to justify. PHMSA's FAQs on the issue make it clear that the qualified individual must be close enough to direct and observe the unqualified individual so that they can recognize and react to abnormal operating conditions and take immediate corrective action, and that the operator must consider all relevant factors, including physical space limitations and environmental conditions such as noise, visual obstructions, and weather.

Some states have gone further with specific limitations. Connecticut limits span of control to exactly one-to-one — one qualified, one unqualified, maximum. New York requires that whatever span of control an operator uses must be justified and documented.

What Regulators Are Really Looking For

The central test is simple: could the qualified person physically step in and take over if something went sideways? Proximity matters.

If two workers are in very close proximity, a two-to-one ratio might be defensible. If they're at opposite ends of a block, it's not. If there's only room in the trench for one person, span of control is practically impossible to justify — regardless of policy.

The Documentation Burden — A Nationwide Issue

The documentation burden is what's driving some operators in the Northeast to reconsider using span of control for OJT altogether. This is not a regional concern — it applies to any operator using span of control as part of their OJT process, anywhere in the country.

The moment span of control is part of how an operator qualifies workers through OJT, documentation becomes an operational requirement, not a best practice. Key documentation considerations include who was the qualified person directing and observing, what covered task(s) was being performed, when it occurred, where it occurred, and how proximity was maintained to allow for immediate intervention.

The regulator's standard is blunt: If you documented it, you did it. If you didn't document it, you didn't do it.

How EWN Can Help

EWN's platform can help operators document who was directing and observing an unqualified worker for the completion of any given covered task — creating a clear, auditable record that ties the qualified person to the specific work performed. Without it, operators may struggle to demonstrate that a covered task was properly supervised or that the worker was legitimately qualified through OJT.

Bottom Line

Span of control remains a viable tool for OJT, but only when it's used with the rigor regulators expect. That means defensible proximity, a justifiable ratio, and documentation that proves the qualified person was actually there, actually observing, and actually capable of stepping in. If your program relies on span of control and your documentation doesn't reflect that level of detail, it's worth a hard look — regardless of where you operate.