How to Fill Out the OSHA 300 Log: A Step-by-Step Guide for Small Employers

The OSHA 300 log — formally, the "Log of Work-Related Injuries and Illnesses" — is the document at the center of your entire recordkeeping obligation. Every recordable incident that happens at your establishment goes on this log, and it stays there for five years. OSHA inspectors ask for it first. Insurers and general contractors ask for it during prequalification. And the data from it feeds directly into your 300A annual summary, your TRIR and DART rate calculations, and — for covered employers — your electronic submission to OSHA's Injury Tracking Application.

Despite its importance, the form itself is not complicated. It is a single page with thirteen columns. The challenge is not filling it out — it is filling it out correctly, on time, and consistently. This guide walks through each section of the log, explains the rules that most commonly lead to errors or citations, and gives you a practical framework for maintaining a log that will hold up if an inspector ever asks to see it.

Who Must Keep a 300 Log

Most employers with 11 or more employees at any point during the previous calendar year must maintain an OSHA 300 log. There are two categories of exceptions. First, employers in certain low-risk industries — listed in Appendix A to Subpart B of 29 CFR Part 1904 — are partially exempt from routine recordkeeping, though they must still report fatalities, hospitalizations, amputations, and losses of an eye. Second, employers with 10 or fewer employees throughout the entire previous calendar year are exempt from routine recordkeeping, with the same reporting exceptions.

There is an important caveat: even if you are normally exempt, the Bureau of Labor Statistics can require you to participate in their annual Survey of Occupational Injuries and Illnesses. If you receive a written notification from BLS, you must keep records for that year regardless of your size or industry.

The Seven-Day Rule

When a recordable injury or illness occurs, you must enter it on the 300 log within seven calendar days of receiving information that a recordable case has occurred. This deadline runs from when you learn the case is recordable, not necessarily from the date of injury. If an employee goes to the doctor on Monday and you learn on Wednesday that the doctor prescribed medication — making the case recordable — your seven-day clock starts on Wednesday.

This is one of the most frequently cited violations because it is trivially easy for an inspector to verify. They compare the date of injury to the date the entry was made. If the gap exceeds seven days, it is a citable violation — up to $16,550 per instance.

Columns A Through F: Identifying the Case

The left side of the 300 log captures basic information about the employee and the incident. Each column has specific requirements:

Column A — Case Number

Assign a unique case number to each recordable incident. OSHA does not mandate a specific format, but most employers use a year-sequence pattern like 2026-001, 2026-002, and so on. Whatever system you use, each number must be unique within the calendar year and establishment. This number links the 300 log entry to the corresponding 301 incident report.

Column B — Employee Name

Enter the full legal name of the injured or ill employee. There is one exception under 29 CFR 1904.29(b)(7): for cases involving certain "privacy concern" conditions — including mental illness, HIV/AIDS, hepatitis, sexual assault, needlestick injuries involving contamination with another person's blood, and certain reproductive disorders — you may enter "privacy case" instead of the employee's name. You must still keep a separate, confidential list linking case numbers to employee names.

Column C — Job Title

Enter the employee's job title at the time of the injury. Be specific enough to be meaningful — "Technician" is less useful than "HVAC Technician" or "Lab Technician." This information is used to identify whether certain job roles are disproportionately represented in your injury data.

Column D — Date of Injury or Illness Onset

For injuries, enter the date the incident occurred. For illnesses, enter the date of initial diagnosis or the date the employee first became aware of the condition, whichever comes first. If you cannot determine the exact date, use the best estimate available.

Column E — Where the Event Occurred

Describe the specific location within the establishment where the incident happened. Be as precise as practical. "Loading Dock B" is useful for identifying a hazard pattern. "Warehouse" is not. If the incident occurred off-site but during work-related activity, describe the location (e.g., "Customer site at 400 Main St, Suite 200").

Column F — Description of Injury or Illness

This is the most important column on the form for hazard analysis purposes. Describe the injury or illness, the body part affected, and the object or substance that caused it. OSHA wants enough detail to understand what happened. Good example: "Laceration to left index finger from box cutter while opening shipping carton." Poor example: "Cut on hand."

Columns G Through J: Classifying the Case

Every recordable case must be classified into exactly one of four categories. You check the single column that reflects the most serious outcome of the case:

• Column G — Death: Check this if the employee died as a result of the work-related injury or illness. You must also report the fatality to OSHA within eight hours.
• Column H — Days away from work: Check this if the employee missed one or more days of work because of the injury or illness (not counting the day of the injury itself).
• Column I — Job transfer or restriction: Check this if the employee remained at work but was placed on restricted duty or transferred to a different job.
• Column J — Other recordable cases: Check this if the case was recordable (e.g., medical treatment beyond first aid, loss of consciousness, or a significant diagnosed condition) but did not result in death, days away, or restriction/transfer.

You must select the most serious applicable outcome. If an employee initially receives medical treatment (Column J) but is later put on restricted duty, you cross out the check in Column J and place a new check in Column I. If the employee is eventually sent home to recover, you cross out Column I and check Column H. The classification must always reflect the most serious outcome as of the current date.

Columns K and L: Counting Days

If you checked Column H or Column I, you must enter the number of calendar days in Columns K and L respectively.

Column K captures the number of days the employee was away from work. Column L captures the number of days the employee was on job transfer or restricted duty. The counting rules are specific and frequently misunderstood:

• Do not count the day of the injury itself. Day counting begins the day after the incident.
• Count calendar days, not scheduled work days. Weekends, holidays, and days the employee was not scheduled to work all count if the employee would have been unable to work or was under restriction.
• Cap the count at 180 days per case. If the employee is still away or restricted after 180 days, enter 180 and stop counting.
• If an employee is on both days away and restricted duty at different points during recovery, enter the days away in Column K and the restricted days in Column L. The classification in Column H or I should reflect the most serious outcome.

Column M: Injury or Illness Type

The final section of the 300 log asks you to classify the case as either an injury or one of five illness categories:

• Column M-1 — Injury: Any wound or damage to the body resulting from a single instantaneous event in the work environment (cuts, fractures, burns, sprains, etc.).
• Column M-2 — Skin disorder: Conditions such as contact dermatitis, chemical burns to the skin, or rashes caused by workplace exposures.
• Column M-3 — Respiratory condition: Conditions such as silicosis, asbestosis, occupational asthma, or reactive airway disease from workplace inhalation exposures.
• Column M-4 — Poisoning: Disorders caused by ingestion, inhalation, absorption, or injection of toxic substances in the workplace.
• Column M-5 — Hearing loss: Recordable standard threshold shifts in hearing as measured by audiometric testing under 29 CFR 1904.10.
• Column M-6 — All other illnesses: Any work-related illness not covered by the categories above, including heat illness, bloodborne pathogen infections, and musculoskeletal disorders that develop over time.

Check exactly one column per case. If a case involves both an injury and an illness component, classify it based on the primary condition.

The Annual Summary Row

At the bottom of the 300 log, you must total each column at the end of the calendar year. These totals feed directly into the 300A annual summary. Make sure your totals are arithmetically correct — an inspector checking your 300A against your 300 log will notice if the numbers do not match, and a discrepancy is a red flag that triggers a closer look at your records.

Retention and Employee Access

You must retain your OSHA 300 log for five years following the end of the calendar year it covers. During that five-year window, the log is a living document — you must update it to reflect new cases, changes in classification, or cases that are later determined not to be recordable.

Current and former employees, their personal representatives, and their authorized employee representatives have the right to access the 300 log. You must provide a copy of the log for the current year and the four preceding years by the end of the next business day after a request is made. The 301 incident report is more restricted — only information about the requesting employee's own case must be provided.