What is an OSHA 300 Log?
The OSHA 300 Log, formally known as the Log of Work-Related Injuries and Illnesses, is a federally mandated recordkeeping document. It's required under OSHA's recordkeeping rule (29 CFR Part 1904) for most employers with 11 or more employees.
The log captures every qualifying work-related incident that occurs during the calendar year, including injuries, illnesses and their outcomes. It's not just a compliance form. It gives safety managers a clear picture of workplace hazards over time and supports data-driven decisions to prevent future incidents.
Alongside 300AForm (Annual Summary) and Form 301 (Injury and Illness Incident Report), it forms the core of OSHA's injury and illness recordkeeping system.
What's Included in an OSHA 300 Log?
A complete OSHA 300 Log captures key details about each recordable case from start to finish. Here's what each entry should include:
Case Information:
Case number: A unique identifier for tracking and referencing each incident (e.g., Case #001)
Employee name: Full name of the injured or ill worker
Job title: The employee's role at the time of the incident (e.g., Forklift Operator)
Date of injury or onset of illness: When the incident occurred or the illness began
Where the event occurred: The specific location on the worksite (e.g., Warehouse Floor, Loading Dock)
Description of injury or illness: A brief account of what happened and the body part affected (e.g., "Employee slipped on wet floor, fracturing right wrist")
Classification of the case:
Death: Check if the incident resulted in a fatality
Days away from work: Number of calendar days the employee was unable to work
Days of job transfer or restriction: Number of days the employee was on modified or restricted duty
Other recordable cases: Injuries or illnesses that don't result in days away but still require medical treatment beyond first aid
Type of Injury or Illness:
Injury
Skin disorder
Respiratory condition
Poisoning
Hearing loss
All other illnesses
How do I fill out an OSHA 300 Log?
To fill out an OSHA 300 Log, start by determining whether an incident is OSHA-recordable. Not every workplace injury qualifies. Focus on injuries and illnesses that are work-related and result in one of the following: days away from work, restricted duty or job transfer, medical treatment beyond first aid, loss of consciousness or a diagnosis of a significant injury or illness by a licensed healthcare professional.
When completing each entry:
Enter the case number and date as soon as you determine the incident is recordable.
Describe the injury or illness clearly, including what happened and which body part was affected.
Classify the case accurately using the correct columns on the form.
Count and record the number of days away from work or days on restricted duty separately.
Identify the type of injury or illness using the right-hand columns.
Review open entries throughout the year to keep day counts current as the case progresses.
At year end, transfer the totals from Form 300 to Form 300A. Have a company executive certify the summary, then post it by February 1 of the following year.
Example of an OSHA 300 Log
Consider a manufacturing facility where a worker reports a back injury after manually lifting heavy equipment. The safety manager records the following:
Case #007
Employee : Maria Santos Job Title : Assembly Line Worker Date of injury : March 14, 2026 Location : Assembly Floor B. Description : Employee reported lower back strain after lifting a 50 lb component without mechanical assistance. Classification : 8 days away from work, followed by 5 days of restricted duty. Type : Injury.
The entry is completed within 7 calendar days of the report. Day counts are reviewed and updated weekly until the employee returns to full duty. At year end, the case totals are transferred to the 300A Annual Summary and certified before the February 1 posting deadline.
Common OSHA 300 Log Mistakes to Avoid
Misclassifying the severity of a case
Each recordable case gets only one classification, the most serious outcome. If an employee misses three days of work before returning on restricted duty, only the "days away from work" column should be checked, not both. Checking multiple classification columns for a single case will throw off your page totals and create discrepancies that can draw scrutiny during an inspection. As a rule, always work from the most severe outcome downward: death → days away from work → job transfer or restriction → other recordable cases.
Miscounting days away from work
OSHA counts calendar days, not scheduled workdays. Weekends, holidays, and days the employee wouldn't have worked anyway all count toward the total. The one exception: the day the injury occurred or illness began is never counted as a day away from work. The maximum you can record for any single case is 180 calendar days. This is one of the most common arithmetic errors on the log, and it directly affects your DART rate.
Writing vague injury descriptions
Column F requires three things: what happened, which body part was affected, and what object or substance caused the injury or illness. Entries like "back injury" or "employee hurt hand" are incomplete. A properly written description looks like: "Employee strained lower back while manually lifting a 50 lb component; no mechanical assist available." Incomplete descriptions are a frequent citation point during OSHA record reviews.
Failing to update open cases
If an employee is still out of work when the year ends, enter an estimate of the expected days and circle it to indicate the number is still being tracked. When the case resolves, update the entry. Leaving cases open and unresolved or forgetting to revise initial estimates leads to inaccurate annual totals that carry over to the 300A Summary.
Having the wrong person certify the 300A
The Form 300A Annual Summary must be signed by a company executive: an owner, corporate officer, the highest-ranking official at the establishment, or that person's immediate supervisor. A safety manager or HR director does not qualify unless they also hold one of those roles. OSHA treats an improperly signed 300A as an uncertified form, which is a recordkeeping violation regardless of whether the underlying data is accurate.
Confusing establishment size with company size
Recordkeeping requirements apply at the company level, not the individual establishment level. If your company has 11 or more employees in total, every establishment must maintain its own OSHA 300 Log even locations with only a handful of workers. Each establishment's log must reflect only the incidents that occurred at that location, not company-wide totals.
