A temp worker from a staffing agency cuts his hand on your production line. He's not on your payroll. The agency hired him, pays him, handles his benefits, and ran his drug screen. The agency's contract even says it "handles all OSHA matters" for its placed workers.
So whose OSHA 300 Log does the injury go on?
Yours, almost certainly. Under 29 CFR 1904.31, the recording obligation follows day-to-day supervision of the work — not the paycheck, not the W-2, and not the contract. In the typical staffing arrangement, the host employer directs the work, which means the host employer keeps the record. OSHA's own guidance under the Temporary Worker Initiative puts it plainly: "In most cases, the host employer is the one responsible for recording the injuries and illnesses of temporary workers."
This is one of the most consistently misunderstood rules in Part 1904, and it's especially relevant right now — summer is peak season for temporary and seasonal labor, and OSHA's expanded electronic reporting rules make the host's injury data more visible to the agency than ever. This post walks through the supervision test, the one-log rule, the edge cases (PEOs, leased workers, contractors, day laborers), and how temp workers flow into your hours, your rates, and your ITA submission.
What 29 CFR 1904.31 Actually Says
The rule that governs whose log a case belongs on is short. Section 1904.31(a) sets the basic requirement:
You must record on the OSHA 300 Log the recordable injuries and illnesses of all employees on your payroll, whether they are labor, executive, hourly, salary, part-time, seasonal, or migrant workers. You also must record the recordable injuries and illnesses that occur to employees who are not on your payroll if you supervise these employees on a day-to-day basis.
Read that second sentence again. Payroll status is irrelevant if you supervise the worker day to day. The implementation question at 1904.31(b)(2) removes any doubt about staffing arrangements specifically:
If I obtain employees from a temporary help service, employee leasing service, or personnel supply service, do I have to record an injury or illness occurring to one of those employees? You must record these injuries and illnesses if you supervise these employees on a day-to-day basis.
The same logic applies to contractor employees under 1904.31(b)(3): if the contractor supervises its own people day to day, the contractor records. If you supervise the contractor's employee day to day, you record.
The One-Log Rule
Every recordable injury belongs on exactly one log. Section 1904.31(b)(4) addresses the question directly — if the host records the case, does the staffing agency record it too?
No, you and the temporary help service, employee leasing service, personnel supply service, or contractor should coordinate your efforts to make sure that each injury and illness is recorded only once: either on your OSHA 300 Log (if you provide day-to-day supervision) or on the other employer's OSHA 300 Log (if that company provides day-to-day supervision).
Double-recording is itself an error. It distorts the national injury data the recordkeeping system exists to produce, and it inflates one employer's rates for a case that doesn't belong to them. The rule expects the host and the agency to communicate about injuries — but only one of them puts the case on a 300 Log.
The One-Log Rule
Each injury is recorded once, on the log of the employer that provides day-to-day supervision (29 CFR 1904.31(b)(4)). The host and the staffing agency should coordinate so the case lands on exactly one log — never both, never neither.
What "Day-to-Day Supervision" Means
The entire framework turns on one phrase, so OSHA has defined it carefully. Per the agency's recordkeeping FAQ for Section 1904.31, day-to-day supervision occurs when, "in addition to specifying the output, product or result to be accomplished by the person's work, the employer supervises the details, means, methods and processes by which the work is to be accomplished."
In plainer terms: the supervising employer is the one telling the worker how to do the job, hour by hour — which machine to run, which tasks come first, what the procedure is, when to stop. OSHA's Temporary Worker Initiative bulletin frames it in safety terms: the supervising employer is the one that controls the conditions presenting potential hazards and directs the worker's activities around, and exposure to, those hazards.
HR Functions Are Not Supervision
The most common counterargument hosts raise is that the staffing agency "manages" the worker — it hired them, pays them, approves their time off. OSHA rejected this argument explicitly in an October 19, 2015 letter of interpretation. Activities like processing vacation and leave requests, administering compensation and benefits, and conducting drug screening "would typically be considered human resource activities, and would not rise to the level of day-to-day supervision." Assigning daily tasks, by contrast, constitutes supervising the "details, means, methods, and processes" of the work.
A staffing agency that places a worker on your line and then handles their timesheet from across town is not supervising them. Your shift lead is.
There Is No "Joint" Supervision
What about worksites where supervision genuinely feels shared — an agency team lead on-site relaying instructions, or a prime contractor coordinating subcontractor crews? OSHA forces a single answer. The same 2015 letter states that "there cannot be joint day-to-day supervision of temporary workers," and the agency reiterated the point for prime/subcontractor arrangements in an April 25, 2017 letter: for purposes of OSHA recordkeeping, there cannot be joint day-to-day supervision. One employer directs the details of the work. That employer records.
This position has deep roots. As far back as a July 1992 letter of interpretation, OSHA's view has been that where temps are subject to the using firm's supervision, the staffing service "is acting merely as a personnel department for the using firm, and the using firm must keep the records."
Quick Test: Who Directs the Work?
Day-to-day supervision means controlling the "details, means, methods and processes" of the work — assigning daily tasks, directing procedures, controlling the hazards. Payroll, benefits, scheduling time off, and drug screening are HR functions and do not count. And there is no joint supervision: exactly one employer holds the recording duty for each worker.
Your Contract Cannot Reassign the Duty
This is the part that surprises the most employers, so it deserves its own section. Many staffing contracts include language assigning "all OSHA compliance" or "all recordkeeping obligations" to the agency. Hosts read that clause and assume the matter is handled.
It isn't. From the same October 19, 2015 letter of interpretation:
The determination regarding which entity must record the injuries and illnesses of temporary workers must be based on the actual facts concerning day-to-day supervision at the worksite. This means that the entity that actually provides day-to-day supervision is responsible for recording cases on the OSHA Log regardless of the wording of the parties' contractual arrangements.
The recording duty is a regulatory obligation that attaches to the facts on the ground. A contract can allocate costs, indemnification, and insurance between the parties — it cannot move a federal recordkeeping duty off the employer that actually supervises the work. If OSHA inspects your facility and finds an unrecorded temp worker injury, the citation goes to you, and the contract clause is not a defense.
What contracts should do, per OSHA's Temporary Worker Initiative guidance, is establish communication procedures: the host notifies the agency of injuries, the agency notifies the host of anything it learns through workers' comp claims or medical providers, and both sides confirm who is recording. That coordination is exactly what 1904.31(b)(4) contemplates — and it's how cases avoid falling into the gap between two companies that each assume the other one logged it.
Contracts Don't Transfer the Duty
The employer that actually provides day-to-day supervision must record the case "regardless of the wording of the parties' contractual arrangements" (OSHA letter of interpretation, October 19, 2015). A clause saying the staffing agency "handles all OSHA matters" does not move the duty off a host that directs the work.
How Temp Workers Flow Into Your Numbers
Recording the injury is only half of the integration. Supervised temp workers affect every downstream number your recordkeeping produces.
The 300 Log. The supervising employer enters the recordable case on its log, the same as any direct employee's case. You may organize the log so temporary workers are listed in their own section, but per OSHA's June 23, 2003 letter of interpretation, it remains one record — not a separate log — for purposes of employee access and production to the government. The seven-day entry deadline, the classification columns, and the five-year retention rule all apply identically. If you're working through the mechanics, our step-by-step 300 Log guide covers each column.
The 300A hours calculation. OSHA's recordkeeping FAQ for the annual summary is explicit: to calculate total hours worked by all employees, "include the hours worked by salaried, hourly, part-time and seasonal workers, as well as hours worked by other workers you supervise (e.g., workers supplied by a temporary help service)." Supervised temp hours belong in your denominator. The 300A guide covers the rest of the form.
TRIR and DART. Because supervised temps contribute both injuries (numerator) and hours (denominator), getting only half the equation right skews your rates in whichever direction you got wrong. Log their injuries but omit their hours, and your rates are artificially inflated. Count their hours but miss their injuries, and your rates are artificially deflated — which is worse, because deflated rates that don't survive an inspection raise questions about your entire program. The TRIR and DART explainer walks through both formulas.
The ITA submission. Supervised temp data is part of your establishment's electronic submission under 29 CFR 1904.41. And since the 2024 reporting cycle, establishments with 100 or more employees in designated high-hazard industries submit case-level Form 300 and 301 data, not just 300A summaries — meaning OSHA can now see individual temp worker cases, or their absence, in your submitted data. The ITA submission guide covers the process.
This also feeds inspection targeting. Your submitted rates are the raw material for OSHA's Site-Specific Targeting program, and an establishment that systematically omits temp worker cases is producing exactly the kind of suspiciously low rate the SST program's data-quality audits exist to catch.
The Edge Cases
The supervision test resolves most arrangements cleanly, but a few configurations come up often enough to address by name.
PEOs vs. Traditional Staffing Agencies
A professional employer organization is not a staffing agency, but the recordkeeping analysis is identical. In a typical PEO arrangement, the PEO becomes the employer of record for payroll, benefits, and tax purposes, while the client company continues to direct the actual work. Employer-of-record status is an HR function. The client company supervising the details, means, methods, and processes of the work keeps the 300 Log. The co-employment agreement doesn't change this — supervision does.
Leased Workers
Same test. OSHA addressed employee leasing directly in a February 12, 1992 letter of interpretation: the company that has direct supervision over the day-to-day activities of the employees is responsible for the recordkeeping. In most leasing arrangements, that's the client firm where the work happens.
Independent Contractors
Here the answer flips — but only if the worker is genuinely independent. Self-employed individuals are not covered by the OSH Act or the recordkeeping rule at all (1904.31(b)(1)), and the preamble to the 2001 recordkeeping rule states that "independent contractors are not employees; therefore, injuries and illnesses sustained by independent contractors are not recordable under the Recordkeeping rule."
The caution is misclassification. OSHA looks at actual control over the work, not the 1099 on file. A "contractor" who works your schedule, uses your equipment, and takes task-by-task direction from your supervisor looks a lot like a supervised worker under the 1904.31 test. If you're directing the details of the work, don't assume the tax classification protects you from the recording duty.
Day Laborers
Workers obtained through a day-labor service or hiring hall are analyzed under the same supervision test as any other supplied worker. If your crew lead is directing their tasks on your site, the case goes on your log.
Seasonal Direct Hires
No ambiguity here at all. Workers you hire directly for the season are on your payroll, and 1904.31(a) names seasonal workers explicitly. Their injuries go on your log, their hours go in your 300A — full stop.
When the Host Is Exempt From Recordkeeping
What happens when a staffing agency places a worker with a host that doesn't keep OSHA records — a small employer under the size exemption, or an establishment in a partially exempt industry? Per OSHA's recordkeeping FAQ: the agency must record the injuries of employees it supervises day to day, even if those employees work for an exempt host — but the agency need not record injuries of placed workers whom another employer supervises. So if the exempt host supervises the work, the case typically goes unrecorded by either party, because the host has no recording obligation and the agency has no supervision. The exemption analysis runs the same as it does for any employer; supervision just determines whose exemption status matters.
Severe Injury Reporting for Temp Workers
Recording on the 300 Log and reporting severe incidents to OSHA are two separate duties, and the second one moves much faster. Under 29 CFR 1904.39, a work-related fatality must be reported to OSHA within 8 hours, and an in-patient hospitalization, amputation, or loss of an eye within 24 hours.
For temp workers, OSHA's guidance follows the same supervision logic as recordkeeping: the employer providing day-to-day supervision of the worker makes the report. If your temp worker is hospitalized after an incident on your line, the 24-hour clock is running on you — not the staffing agency. And reporting applies to every employer covered by the OSH Act, including those exempt from routine recordkeeping. The notification procedures you build with your staffing agency should account for this clock specifically, because 24 hours is not enough time to figure out whose job it was after the fact.
The Enforcement Risk Is Real
OSHA's Temporary Worker Initiative bulletin states the consequence directly: a host employer that refuses or ignores its duty to record may be subject to an OSHA citation. And the agency has demonstrated repeatedly that it treats Part 1904 recordkeeping failures as citable enforcement matters, not paperwork technicalities.
In December 2022, OSHA cited Amazon following inspections at six warehouse facilities — opened on referral from the U.S. Attorney's Office for the Southern District of New York — for 14 recordkeeping violations, including failing to record injuries and illnesses, misclassifying cases, not recording within the required time, and not providing OSHA with timely injury records, with $29,008 in proposed penalties. As then-Assistant Secretary Doug Parker put it in the accompanying release: "Solving health and safety problems in the workplace requires injury and illness records to be accurate and transparent."
Individual recordkeeping violations are typically classified as other-than-serious, currently capped at $16,550 per violation. But each unrecorded case is its own violation, and under OSHA's Field Operations Manual, instance-by-instance treatment is available where an employer has numerous recordkeeping violations tied to a large number or rate of injuries at the establishment. A workforce that's 30 percent temporary, with none of those workers' cases on the log, is precisely the pattern that turns a paperwork problem into a five- or six-figure one. The broader pattern of citation-generating errors is covered in 5 OSHA recordkeeping mistakes that lead to citations.
One more structural note for multi-site employers: a supervised temp worker is linked to a home establishment the same way a direct employee is, so the multi-establishment rules under 1904.30 determine which of your logs the case lands on.
Independent Contractors Are Different
Genuinely self-employed individuals and independent contractors are not covered by the OSH Act, and their injuries are not recordable on your log (1904.31(b)(1); preamble, 66 FR 6038). But OSHA applies the supervision facts, not the tax label — a "1099 contractor" whose daily work you direct may be a supervised worker under 1904.31.
A Five-Step Decision Checklist
When a temp, leased, or contract worker is injured at your site, work through these steps in order:
- Is the case recordable at all? Run the standard analysis — work-relatedness under 1904.5, recording criteria under 1904.7. Our recordability decision tree and the first aid vs. medical treatment guide cover this. If it's not recordable, neither employer logs it.
- Who directs the details, means, methods, and processes of the work day to day? That employer records. HR functions don't count; contracts don't control; there is no joint answer.
- Record once. The case goes on exactly one 300 Log — the supervising employer's — within seven calendar days.
- Count the hours. If you supervise temp workers, their hours go in your 300A total hours worked, and their cases flow into your TRIR, DART, and ITA submission.
- Notify the other employer. Whichever side of the arrangement you're on, tell the other party about the injury. The agency needs to know for the worker's benefit and its own hazard awareness; the host needs to know about anything reported to the agency first. This is the coordination 1904.31(b)(4) expects.
Bottom Line
The recording duty follows day-to-day supervision of the work — not payroll, not the employment contract, not the staffing agreement. In most temp arrangements, that means the host employer records the injury, counts the worker's hours, and owns the 24-hour severe-injury reporting clock. Settle the supervision question for every supplied worker before an injury happens, put the notification procedure in writing, and make sure each case lands on exactly one log.
This post is general compliance information, not legal advice. Verify current regulatory text against eCFR and your state plan's requirements.