Who's Liable When a Testing Vendor Finds a Safety Hazard On-Site?

Who does OSHA hold responsible when a contracted vendor is on a customer's site?

OSHA's Multi-Employer Citation Policy, CPL 02-00-124, sorts every employer at a shared worksite into one or more of four roles: creating, exposing, correcting, and controlling, and which role an employer holds determines whether it can be cited for a given hazard¹. A mobile hearing test, BAT, or spirometry vendor working inside a customer's facility is almost always an exposing employer, since the vendor's own technicians are physically present and exposed to whatever hazards exist at that site, independent of whether the vendor's work created the hazard. The customer, meanwhile, is frequently a controlling employer under the policy, holding general supervisory authority over the site even when the vendor's technicians are the ones exposed. Both roles carry separate obligations, and a citation can land on either employer, or both, depending on what each one did or failed to do.

What does a vendor have to do if it finds a hazard it didn't create and can't fix itself?

As an exposing employer without authority to correct a hazard, a vendor's technicians satisfy the policy by doing three things: asking the employer that created or controls the hazard to correct it, informing its own employees of the hazard, and taking reasonable alternative protective measures in the meantime². Simply noticing a hazard and saying nothing does not satisfy the standard, and in an extreme case, such as an imminent danger condition, the vendor can be expected to pull its technicians off the hazard entirely rather than continue testing around it. This is also why only exposing employers, not creating or controlling employers who have no workers physically exposed, can be cited under the OSHA General Duty Clause for a hazard not covered by a specific standard.

Role	Definition	Typical party on a testing visit
Creating	Caused the hazardous condition	Whichever party's action or equipment produced the hazard
Exposing	Its own employees are exposed to the hazard	The testing vendor's technicians
Correcting	Responsible for fixing the hazard on a shared undertaking	Facility maintenance or a trade contractor on site
Controlling	General supervisory authority over the site	The host facility/customer

What makes an employer a "controlling employer," and why does that matter to a customer hosting a testing visit?

Controlling employer status comes from having the authority, by contract or by actual practice, to correct safety and health violations itself or require others to correct them, and it carries a duty to exercise reasonable care to prevent and detect violations across the site¹. That duty is lighter than the duty an employer owes its own workforce, and OSHA's policy lists factors that scale it: the pace and nature of the work happening, the controlling employer's knowledge of the other party's safety history, and how frequently it inspects relative to that history. A facility hosting an annual hearing test or BAT collection day is a controlling employer over that visit in nearly every case, since it controls the space the testing happens in, even though it isn't directing the vendor's technical work. Merely pointing out a hazard to a vendor doesn't establish or remove controlling-employer status either way; what matters is the underlying authority over the site.

How Foster handles hazard findings during an on-site testing visit

When Foster's technicians encounter a site condition during a mobile hearing, BAT, or fit testing visit that looks unsafe for an employee to be tested in, or unsafe for the technician to work in, the documented step is the same every time: flag it to the site contact in writing before testing in that location, note it in Foster's visit record, and if the condition can't be reasonably worked around, reschedule that portion of the visit rather than test through it. That protects Foster's own technicians as exposing employees under the policy and gives the customer, as the controlling employer, the notice it needs to correct the condition before the next visit. Customers running on-site testing across multiple locations can fold hazard-flagging into the same visit record Foster already keeps for hearing testing and fit testing compliance, so a facility's safety team sees vendor-flagged conditions in the same place as test completion records rather than a separate email thread. A quote for a multi-site testing program includes this documentation as a standard part of the visit, not an add-on.

Frequently Asked Questions

Can OSHA cite a testing vendor for a hazard the customer's facility created?

Only if the vendor knew or should have known about the hazard and failed to take the steps available to it: requesting correction, informing its own employees, and taking reasonable alternative protective measures. A vendor that does all three generally isn't citable for a hazard it didn't create and couldn't fix itself.

Does a customer become a controlling employer just by having a safety policy for visitors?

No. Controlling employer status comes from actual authority over the site, by contract terms or by how control is actually exercised in practice, not from the existence of a written visitor policy alone.

What should a vendor's technician do if a hazard poses immediate danger?

Remove employees from the hazard and stop work in that location. The multi-employer policy treats failure to do this in an extreme case as its own basis for a citation against the exposing employer.

Sources

• OSHA Directive CPL 02-00-124: Multi-Employer Citation Policy
• OSHA Standard Interpretation, 2001-12-13: Multi-employer worksite two-step analysis