Heat Stroke vs. Heat Exhaustion: First Aid for Oilfield Crews

Heat stroke is the emergency. If a worker in the heat is confused, slurring words, passing out or having a seizure, treat it as heat stroke: call 911 and start cooling them right away, ideally by putting them in cold water up to the neck. Heat exhaustion looks like heavy sweating, headache, nausea, dizziness, weakness and thirst with a clear head. Get that worker out of the heat, give fluids and get them checked by a medical provider. The dividing line is the brain. Any change in how a person thinks or acts means heat stroke until proven otherwise.

The CDC's National Institute for Occupational Safety and Health (NIOSH) warns that in heat stroke, body temperature can rise to 106°F or higher within 10 to 15 minutes (NIOSH, heat-related illnesses). That is why cooling starts before the ambulance arrives, not after.

Side by side

Signs from NIOSH. Note that sweating does not rule out heat stroke. A worker in heavy gear can still be sweating while their temperature climbs.

Heat stroke: what to do

1. Call 911 and give the lease name, gate and directions. Send someone to the road to meet the ambulance if the location is hard to find.
2. Stay with the worker. Move them to shade or an air-conditioned cab or doghouse.
3. Take off outer clothing, including FRs, coveralls and boots if you can.
4. Cool fast. The American Red Cross says the preferred method is immersing the person up to the neck in cold water for 15 minutes or until they are no longer confused. If you cannot immerse them, use ice packs, ice sheets, cooling towels, a cold shower, a cooling vest, or misting and fanning (American Red Cross, heat stroke).
5. If no tub is available, NIOSH says to wet the skin, soak clothing with cool water, put cold wet cloths or ice on the head, neck, armpits and groin, and keep air moving over the worker.
6. Keep cooling until EMS takes over. If the worker stops breathing normally, start CPR.

On a remote pad, plan this before summer. Know where the ice is, what you would put a worker in, and how long it takes an ambulance to find the location.

Heat exhaustion: what to do

• Move the worker out of the heat and give liquids to drink, in frequent sips of cool water.
• Remove unnecessary clothing, including boots and socks.
• Cool them with cold compresses, or have them wash their head, face and neck with cold water.
• NIOSH says to take the worker to a clinic or emergency room for evaluation, and to call 911 if medical care is not available. Have someone stay with them until help arrives.
• Keep watching. Heat exhaustion can turn into heat stroke, and new confusion changes everything above to the heat stroke steps.

The other heat illnesses

• Heat cramps: muscle pain or spasms in the belly, arms or legs. NIOSH advises water plus a snack or a sports drink every 15 to 20 minutes, and says to avoid salt tablets. Get medical help if cramps do not ease within an hour, or the worker has heart problems or is on a low-sodium diet.
• Heat syncope: fainting or dizziness from standing too long or standing up quickly. Sit or lie the worker down in a cool place and have them slowly drink water, clear juice or a sports drink.
• Rhabdomyolysis: muscle breakdown from heat and hard work. Watch for muscle cramps or pain, weakness and dark, tea- or cola-colored urine. NIOSH says to stop work, drink more fluids, get care at the nearest medical facility and ask to be checked for rhabdo with a creatine kinase (CK) blood test.

New and returning workers are most at risk

OSHA points to research showing that almost half of heat-related deaths happen on a worker's first day on the job or first day back after an extended absence, and more than 70% in the first week (OSHA, protecting new workers). Bodies need time to adjust. OSHA's "Rule of 20 percent": on the first day, a new worker should spend no more than 20% of the usual shift in the heat, then add 20% each day after. OSHA's own example for an 8-hour day is no more than 1 hour and 40 minutes in the heat on day one, with at least one rest break, so a new hand reaches a full schedule by the end of the first week.

OSHA also says to keep extra precautions for the first one to two weeks, to use a buddy system and not let new workers work alone, and to cut the duration of work, not its intensity. Existing workers lose heat tolerance too: anyone back after a week or more away, the first hot days of spring, and the first day of a heat wave all call for the same steps. A hand coming off a long rotation counts.

What OSHA requires in Texas

Texas is a federal OSHA state. There is no final federal heat standard yet. OSHA published a proposed heat injury and illness prevention rule in August 2024 (Federal Register), with triggers at an 80°F and a 90°F heat index. It is not in force, and OSHA has signaled a supplemental proposal is coming before any final rule. Today OSHA enforces heat hazards under the General Duty Clause. On April 10, 2026 it updated its heat National Emphasis Program for another five years, including random heat inspections in high-risk industries on days the National Weather Service issues a heat advisory or warning (DOL news release).

What is already required: where there is no clinic or hospital close by, someone on site must be adequately trained in first aid under 29 CFR 1910.151(b). See OSHA first aid requirements for remote oilfield sites. For another West Texas summer emergency, see rattlesnake bite first aid.

Working through a cold snap instead? See our hypothermia, frostbite and trench foot first aid guide.