How Do You Fill Out the OSHA 300 Log?

By Wyatt Cooper · Published October 22, 2026 · 8 min read

Key takeaways

A construction company with more than 10 employees at any time last calendar year keeps an OSHA 300 log; construction is not on the list of partially exempt industries.
A case is recordable if it is work-related, new, and leads to death, days away, restricted work or transfer, medical treatment beyond first aid, loss of consciousness, or a significant diagnosis such as a fracture.
Enter each recordable case on the 300 log and a Form 301 within 7 calendar days, classify it by its most serious outcome, and count days away or restricted as calendar days starting the day after.
At year end, total the log on Form 300A, have a company executive certify it, post it from February 1 to April 30, submit it to OSHA online by March 2 if the establishment had 20 or more employees, and keep the records for five years.

To fill out the OSHA 300 log, enter each work-related injury or illness that is recordable under 29 CFR 1904 within 7 calendar days: a case number, the worker's name and job title, the date, where it happened and what the injury was. Check one box for its most serious outcome, count the days away or restricted, and mark the injury or illness type. Total the year on Form 300A.

Who keeps a 300 log on a construction job

If your company "had 10 or fewer employees at all times during the last calendar year", you don't keep the records unless OSHA or the Bureau of Labor Statistics informs you in writing that you must, and the count is by peak employment of the whole company (29 CFR 1904.1). The other exemption is by industry, and the industries in Appendix A to Subpart B are retail, finance, professional services and the like; no construction code is on the list (Part 1904). Every employer, exempt or not, still reports a fatality, in-patient hospitalization, amputation or loss of an eye.

Whose log. You record the injuries of everyone on your payroll and of workers you "supervise on a day-to-day basis". A sub's worker supervised by the sub goes on the sub's log, not the GC's (1904.31).
Which log. You keep a separate log for each establishment "expected to be in operation for one year or longer"; job sites that will last less than a year can share one log, for example one per division or region (1904.30).
How fast. Each recordable case goes on the 300 log and a Form 301 "within seven (7) calendar days of receiving information that a recordable injury or illness has occurred" (1904.29).

Recordable or not: construction cases

A case is recordable if it is work-related, a new case, and meets a general recording criterion: "death, days away from work, restricted work or transfer to another job, medical treatment beyond first aid, or loss of consciousness", or a significant injury or illness diagnosed by a physician or licensed health care professional (1904.7). The rule's first-aid list is complete: anything not on it is medical treatment.

Common construction cases and how 29 CFR 1904.7 classifies them
Case	Recordable?	Why
Cut hand closed with sutures or staples	Yes	Sutures and staples are medical treatment
Cut hand closed with butterfly bandages or Steri-Strips	No, if nothing else applies	On the first-aid list
Metal sliver in the eye flushed out with water	No, if nothing else applies	Removing foreign bodies from the eye by irrigation or a cotton swab is first aid
Sliver removed from the eye any other way	Yes	Not on the first-aid list, so medical treatment
Strained back, told to take an over-the-counter drug at prescription strength	Yes	A recommendation to use a nonprescription drug at prescription strength is medical treatment
Strained back, ice, an elastic wrap, back to full duty	No	Cold therapy and non-rigid support are first aid
Tetanus shot after a nail puncture, wound cleaned	No, if nothing else applies	Tetanus immunizations and cleaning wounds are first aid
Fractured toe, no treatment or restriction	Yes	A fractured or cracked bone is always recorded when diagnosed
Worker knocked out briefly by a falling object	Yes	Any loss of consciousness
Doctor restricts a laborer from lifting over 25 pounds for a week	Yes, as restricted work	If lifting is a routine function, one the worker performs at least once a week
Restriction for the rest of the injury day only	Not as restricted work	The day of injury doesn't count
Clinic visit for observation and an X-ray, nothing found	No	Observation and diagnostic procedures are not medical treatment

A worked incident report that reaches this decision is in how to write a construction incident report.

Columns A to M, in order

The OSHA Form 300 columns and what goes in each, from OSHA's forms package
Column	What goes in it
(A) Case no.	Your number for the case; it carries over to Form 301
(B) Employee's name	Or "privacy case" for an intimate body part, sexual assault, mental illness, HIV, hepatitis or tuberculosis, a contaminated needlestick or sharps cut, or an illness the worker asks to keep private
(C) Job title	For example, laborer or pipefitter
(D) Date of injury or onset of illness	Month and day
(E) Where the event occurred	For example, "Level 3, north stair"
(F) Describe the injury or illness	Body part affected, and the object or substance that caused it
(G)–(J) Most serious outcome	Check one only: (G) death, (H) days away from work, (I) job transfer or restriction, (J) other recordable case
(K) Days away and (L) days transferred or restricted	Calendar days, counted from the day after the injury, weekends and holidays included; you may stop at 180
(M) Injury or illness type	(1) injury, (2) skin disorder, (3) respiratory condition, (4) poisoning, (5) hearing loss, (6) all other illnesses

If a case gets worse, update it: the forms package says to revise the log "if the injury or illness progresses and the outcome is more serious than you originally recorded" (OSHA recordkeeping forms).

A worked example: one sub's year and its 300A

A fictional mechanical sub's 300 log for one year, three recordable cases. Names are left off here.
(A)	(C) Job title	(D) Date	(E) Where	(F) Injury	Outcome	(K) Away	(L) Restricted	(M)
1	Sheet metal apprentice	3/12	Level 2, east corridor	Cut left palm, duct edge; 4 sutures	(J) Other recordable	0	0	(1) Injury
2	Pipefitter	5/6	Mechanical room	Lower back strain lifting pipe; no lifting over 25 lb for 10 days	(I) Restriction	0	10	(1) Injury
3	Sheet metal worker	8/20	Roof, unit curb	Fractured right wrist, fall from ladder; cast	(H) Days away	14	0	(1) Injury

Form 300A — Ridgeline Mechanical, one calendar year

(G) Deaths: 0
(H) Cases with days away: 1
(I) Cases with transfer or restriction: 1
(J) Other recordable cases: 1
(K) Total days away: 14
(L) Total days of transfer or restriction: 10
(M)(1) Injuries: 3
Annual average number of employees: 91 (182,000 hours ÷ 2,000)
Hours worked by all employees: 182,000
Total recordable case rate: 3 × 200,000 ÷ 182,000 = 3.30
Days-away case rate: 1 × 200,000 ÷ 182,000 = 1.10
DART rate (days away, restricted or transferred): 2 × 200,000 ÷ 182,000 = 2.20
Certified, posted and submitted: Certified by a company officer; posted February 1 to April 30; submitted to OSHA's Injury Tracking Application by March 2 (a construction establishment with 20 to 249 employees, 1904.41(a)(1)(i))

The year's Form 300A totals and the case rate OSHA's forms package explains, for the fictional sub.

The 200,000 in the formula is "the number of hours 100 employees working 40 hours per week, 50 weeks per year would work" (forms package). At year end you review the log, total it, and a company executive certifies the summary: an owner of a sole proprietorship or partnership, an officer of the corporation, the highest-ranking official at the establishment, or that person's immediate supervisor. Post it "no later than February 1" and keep it up "until April 30" (1904.32); keep the log, summary and 301s for five years (1904.33).

A construction establishment with 20 to 249 employees at any time in the year must also submit the 300A to OSHA electronically by March 2 (1904.41). One with 100 or more employees classified in NAICS 2381 (foundation, structure and building exterior contractors) submits its 300 and 301 data too.

More for your trade in the subcontractor's guide, and how the records fit into an inspection in how to prepare for an OSHA inspection.

The bottom line

Decide recordability from the rule's own lists, enter each case within 7 calendar days by its most serious outcome, count calendar days from the day after, and update the entry if the case gets worse. Total, certify and post the 300A each February.

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Sources

29 CFR Part 1904, Recording and Reporting Occupational Injuries and Illnesses (incl. Appendix A to Subpart B) — eCFR (Office of the Federal Register). Read October 22, 2026.
29 CFR 1904.1, Partial exemption for employers with 10 or fewer employees — eCFR (Office of the Federal Register). Read October 22, 2026.
29 CFR 1904.7, General recording criteria — eCFR (Office of the Federal Register). Read October 22, 2026.
29 CFR 1904.29, Forms — eCFR (Office of the Federal Register). Read October 22, 2026.
29 CFR 1904.30, Multiple business establishments — eCFR (Office of the Federal Register). Read October 22, 2026.
29 CFR 1904.31, Covered employees — eCFR (Office of the Federal Register). Read October 22, 2026.
29 CFR 1904.32, Annual summary — eCFR (Office of the Federal Register). Read October 22, 2026.
29 CFR 1904.33, Retention and updating — eCFR (Office of the Federal Register). Read October 22, 2026.
29 CFR 1904.41, Electronic submission of Employer Identification Number (EIN) and injury and illness records to OSHA — eCFR (Office of the Federal Register). Read October 22, 2026.
OSHA Forms for Recording Work-Related Injuries and Illnesses (300, 300A, 301) — Occupational Safety and Health Administration. Read October 22, 2026.

Questions

Do small construction companies have to keep an OSHA 300 log?

Only if the company had more than 10 employees at any time during the last calendar year, counted company-wide. Construction is not a partially exempt industry. Every employer must still report fatalities within 8 hours and in-patient hospitalizations, amputations or losses of an eye within 24.

Does the GC record a subcontractor's injury?

Only if the GC supervises that worker day to day. Normally the sub supervises its own crew, so the case goes on the sub's log. The two employers should coordinate so each case is recorded once.

Do you count the day of the injury as a day away?

No. Start counting the day after the injury, count calendar days whether or not the worker was scheduled, and you may stop at 180.

How long must OSHA 300 logs be kept?

Five years following the end of the calendar year they cover, together with the privacy case list, the 300A summary and the 301 reports. Update stored logs for newly discovered cases or changed outcomes.