A tech calls in from a changeout at six in the evening. He is on his way to the hospital, somebody else is driving, and he is not sure yet how bad it is. The owner grabs keys and goes.
The shop line does not care. The evening a tech gets hurt is not a slow evening. A no heat call has no idea the owner is standing in a waiting room, and the phone rings at exactly the rate it always rings. The same person is now the one who has to make a call to OSHA on a clock and the one who normally answers the phone, and both of those land in the same hour.
Having 10 or fewer employees exempts your company from keeping the OSHA 300 log. It does not exempt you from reporting. A work related fatality is an eight hour report and an in-patient hospitalization, amputation, or loss of an eye is a twenty four hour report, at every employer regardless of size. No construction NAICS code appears on OSHA’s partially exempt industry list, so for an HVAC shop, headcount is the only exemption available.
Ten employees means the whole company, not one truck
29 CFR 1904.1 is the exemption most shop owners have heard of. A company with 10 or fewer employees at all times during the previous calendar year does not have to keep OSHA injury and illness records, unless OSHA or the Bureau of Labor Statistics tells the company in writing that it must.
Two details in that section trip people up. Under 1904.1(b)(1) the count is the number of employees in the entire company, not per establishment, not per location, not per truck. Under 1904.1(b)(2) the test is peak employment during the last calendar year, so if you were over 10 at any single point, the exemption is gone for the year. The summer helper counts.
There is a second, separate exemption in 1904.2 for establishments in the industry groups listed in Appendix A to Subpart B. It does not help you. The lowest NAICS code on that list is 4412, and no code beginning 236, 237, or 238 appears on it anywhere. NAICS 238220, Plumbing, Heating, and Air-Conditioning Contractors, is not there. Construction and the specialty trades are not industry exempt, full stop.
OSHA puts the limit of both exemptions in a note on that same page: “All employers, including those partially exempted by reason of company size or industry classification, must report to OSHA any employee’s fatality, in-patient hospitalization, amputation, or loss of an eye.”
The clock starts when the news reaches you or your agent
Section 1904.39 sets the two deadlines. Eight hours for a fatality. Twenty four hours for an in-patient hospitalization of one or more employees, an amputation, or the loss of an eye.
The paragraph worth reading twice is 1904.39(b)(7), which covers the case where you were not standing there when it happened. The regulation says you report “within the following time period after the fatality, in-patient hospitalization, amputation, or loss of an eye is reported to you or to any of your agent(s): Eight (8) hours for a fatality, and twenty-four (24) hours for an in-patient hospitalization, an amputation, or a loss of an eye.”
Read the phrase “to you or to any of your agent(s)” again. The clock is not tied to the moment the owner personally listens to the voicemail. If the report lands with somebody acting on the shop’s behalf, the period has started.
That is the practical reason a message about a hurt tech cannot sit in a queue until morning. It is not a paperwork preference. It is the difference between a report that is on time and one that is late, decided by a phone call that arrived while the office was closed.
Two more timing rules sit alongside it. Under 1904.39(b)(6) a fatality is reportable only if the death occurs within 30 days of the work related incident, and a hospitalization, amputation, or loss of an eye is reportable only if it occurs within 24 hours of the incident.
Emergency room treatment is not in-patient hospitalization
Half the reporting decisions a shop makes turn on definitions, not judgment.
In-patient hospitalization means formal admission to the in-patient service of a hospital or clinic for care or treatment. Treatment in an emergency room only is not reportable, and neither is a hospitalization for diagnostic testing or observation only. An amputation is the traumatic loss of all or part of a limb or other external body part, and OSHA counts fingertip amputations with or without bone loss, medical amputations resulting from irreparable damage, and parts that have since been reattached.
Two events are carved out. A motor vehicle accident on a public street or highway is not reportable unless it happened in a construction work zone. Anything that happens on a commercial or public transportation system, such as an airplane or a bus, is not reportable either. For a temporary worker, the employer that provides day to day supervision makes the report, which for a shop using a staffing agency helper is usually the shop.
Run those definitions against the way HVAC techs actually get hurt and most calls sort themselves quickly. A brazing burn dressed on site and sent home is not reportable, which does not make it small, and the fire watch rules around hot work exist because the same torch has a worse version of that day in it. A tech who comes through a ceiling and gets admitted overnight is a twenty four hour report, and how your crews get into attics and crawlspaces decides how often you make that call. An arc at a contactor can produce all three outcomes at once, which is why the rules around taking live readings are worth knowing before the day you need them.
What actually changes when you pass ten
Once the company was over 10 at any point in the previous calendar year, you keep records.
Section 1904.7 makes an injury or illness recordable when it results in death, days away from work, restricted work or transfer to another job, medical treatment beyond first aid, loss of consciousness, or a significant injury or illness diagnosed by a physician or other licensed health care professional. First aid is a closed list in 1904.7(b)(5)(ii): non-prescription medication at non-prescription strength, tetanus shots, cleaning or flushing surface wounds, bandages and butterfly closures, hot or cold therapy, non-rigid supports such as elastic wraps, temporary immobilization used to transport the injured worker, draining a blister, eye patches, simple splinter and foreign body removal, finger guards, massage, and fluids for heat stress. Visits solely for observation or counseling do not count as treatment, and neither do x-rays or blood tests.
Then 1904.32 asks you to total the 300 log columns, complete the 300A annual summary, have a company executive certify it, and post it where employee notices are normally posted no later than February 1 of the following year, kept up until April 30. The certifier is defined narrowly: an owner only if the business is a sole proprietorship or partnership, an officer of the corporation, the highest ranking company official working at the establishment, or that person’s immediate supervisor. Under 1904.33 all of it is kept five years past the end of the year it covers, and the 300 log has to be updated during those five years as new cases surface and classifications change. The 300A and the 301s do not.
Eleven is not the electronic filing number, and neither is twenty five
Three different thresholds get collapsed into one in most shop owners’ heads, and they govern different things.
Electronic submission under 1904.41 starts at 250 employees for the 300A, at 20 to 249 employees for establishments in the industries listed in Appendix A to Subpart E, and at 100 to 249 employees for the fuller 300, 300A and 301 submission under Appendix B. The deadline is March 2 of the following year. A shop under 20 people is not in that program at all, even after it has lost the log exemption at eleven.
Penalties use a third number, and it moved recently in small shops’ favor. OSHA’s memorandum of May 21, 2026 confirms there are no inflation based increases to civil penalties for 2026, so the 2025 amounts carry forward: $16,550 per violation for Serious, Other-Than-Serious and Posting Requirements, $165,514 per violation for Repeat and Willful, and $16,550 per day for Failure to Abate beyond the abatement date, generally capped at 30 days. The same memo describes revisions to Chapter 6 of OSHA’s Field Operations Manual effective July 14, 2025 that widened the maximum general size based penalty reduction from employers with 1 to 10 employees out to employers with 1 to 25, raising the reduction available at 11 to 25 employees from 60 percent to 70 percent. For serious willful violations the group eligible for an 80 percent reduction went from 10 or fewer employees to 20 or fewer, and the history reduction went from 10 percent to 20 percent.
Worth noticing that Posting Requirements carries its own $16,550 maximum. The 300A posting window is the easiest item on this entire list to forget.
Many states run their own OSHA approved State Plans, which must be at least as effective as federal OSHA and are free to be stricter on reporting and recordkeeping. Check yours rather than treating the federal rule as a ceiling. That is also how a shop ends up inside an enforcement program it never read, the way the heat emphasis program reaches attic work.
Have the report path written down before you need it
There are exactly three ways to report: the nearest OSHA Area Office by phone or in person, the toll free line at 1-800-321-OSHA (1-800-321-6742), or the Serious Event Reporting online form on OSHA’s site. If the Area Office is closed, 1904.39(b)(1) requires the 800 number or the online form. A voicemail on the Area Office machine, a fax, or an email does not satisfy the rule.
Have ready what OSHA asks for: establishment name, location and time of the incident, type of event, number of employees affected, their names, a contact person with a phone number, and a short description.
Dial72 does not make that report and does not track injuries. It answers customer calls. The narrow part it covers is the other half of that evening, when an owner sitting in a hospital at eight o’clock still has a shop line ringing. Dial72 picks up in under a second, 24/7, triages by your rules so a no heat call in hard weather escalates to whoever is on call, books the rest straight into your calendar, and texts you a summary in English or Spanish. That keeps the business from going dark while you deal with the person who got hurt. It is not compliance software, and nothing about it changes the eight or twenty four hour deadline.
What to do this week
Count your peak headcount across the entire company for last calendar year, not your headcount today, and write the number down. Name the people who take after hours calls and tell them in plain words that an injury message goes to a human immediately, not into tomorrow’s callback list.
Put the 800 number, the online form, and OSHA’s required information list somewhere the on call person can reach at two in the morning. If your after hours coverage is the weak link in that chain, it is worth working through what the actual options are before the night you find out. Dial72’s tiers run $95, $295 and $495 flat per month, priced by plan rather than by headcount, and are laid out at pricing.
Then keep the reporting call yourself, or hand it to one named person who can act the moment the news arrives. The clock does not wait for the office to open.
