First aid is the immediate care you give to an injured or ill person before professional medical help arrives. It’s guided by three core goals, often called the three Ps: preserve life, prevent further injury, and promote recovery. Every action in first aid, from pressing a cloth against a wound to positioning someone in shock, ties back to one of those three principles.
You don’t need medical training to perform basic first aid. Most techniques are simple, physical actions that buy time until paramedics take over. Knowing even a handful of them can make the difference between a minor outcome and a serious one.
The Three Steps of Any Emergency
The American Red Cross teaches a framework called Check, Call, Care. It applies to virtually every emergency you might encounter. First, check the scene for safety. If there’s a downed power line, active traffic, or a chemical spill, you can’t help anyone if you become a victim yourself. Once you’re sure the area is safe, check the person. Are they conscious? Breathing? Bleeding?
Next, call 911 (or have someone nearby do it). You should call immediately if the person is unresponsive, not breathing or only gasping, having trouble breathing, or bleeding severely. Put the dispatcher on speakerphone. They’re trained to walk you through specific responses like CPR or choking rescue in real time.
Finally, care for the person based on what you observe and what you know how to do. That care will look different depending on the situation, but the sections below cover the most common emergencies.
CPR: When Someone Stops Breathing
If a person is unresponsive and not breathing normally, CPR keeps blood flowing to the brain until paramedics arrive. The 2025 American Heart Association guidelines recommend 30 chest compressions followed by 2 rescue breaths, repeating in cycles. Push hard and fast in the center of the chest, aiming for visible chest rise when you give breaths. Avoid giving breaths that are too large or too frequent, as over-inflating the lungs can actually reduce blood flow.
If you’re untrained or uncomfortable giving rescue breaths, hands-only CPR (continuous compressions without breaths) is still far better than doing nothing. Keep going until emergency services arrive or the person starts breathing on their own.
Choking: Back Blows and Abdominal Thrusts
A person who is truly choking can’t talk, cough forcefully, cry, or laugh. If they can still cough or speak, encourage them to keep coughing. If they can’t, act fast with the “five-and-five” method recommended by the Red Cross.
Stand to the side and slightly behind the person. Bend them forward at the waist and deliver five firm strikes between the shoulder blades with the heel of your hand. If that doesn’t clear the blockage, move to five abdominal thrusts: stand behind the person, wrap your arms around their waist, place your fist just above the navel, and thrust inward and upward. Alternate between five back blows and five abdominal thrusts until the object comes free. For a child, kneel down behind them to get to the right height.
Severe Bleeding
Heavy bleeding can become life-threatening within minutes. The single most important step is applying direct pressure to the wound immediately, using whatever you have: gauze, a clean shirt, even your bare hands if nothing else is available. Press firmly and hold. Don’t lift the cloth to check on the bleeding, as this interrupts clot formation. Place the injured body part on a firm, flat surface if possible.
For life-threatening bleeding on an arm or leg, a tourniquet can be applied if one is available and you’ve been trained to use it. For wounds on the scalp, neck, shoulder, groin, or back where a tourniquet isn’t practical, packing the wound tightly with gauze or cloth and maintaining pressure is the recommended approach. Once bleeding stops, secure the dressing with a roller bandage and keep monitoring until help arrives.
Burns
Burns fall into three categories. First-degree burns affect only the outer skin layer, causing redness, pain, and swelling. Second-degree burns go deeper, producing blisters along with redness and swelling. Third-degree burns penetrate the full thickness of the skin and may look white or blackened. The skin may actually feel numb because nerve endings are destroyed.
For minor burns (any first-degree burn, or a second-degree burn smaller than about 3 inches across), run cool water over the area for at least 5 to 30 minutes. Not ice water, just cool. This draws heat out of the tissue and reduces damage. For severe or third-degree burns, do not immerse the area in cold water, as this can trigger shock. Cover the burn loosely with a clean, dry cloth and wait for emergency medical help.
Recognizing a Stroke
Stroke kills brain tissue every minute it goes untreated, so recognition speed matters enormously. The American Stroke Association uses the FAST acronym:
- Face: Ask the person to smile. Is one side of the face drooping or twisting?
- Arms: Ask them to raise both arms. Does one drift downward?
- Speech: Ask them to repeat a simple phrase. Is their speech slurred or strange?
- Time: If you see any of these signs, call 911 immediately.
There is no first aid “treatment” for a stroke. Your role is to recognize it and get emergency help as fast as possible.
Seizures
Watching someone have a seizure can be frightening, but the best thing you can do is stay calm and keep them safe. Ease the person to the ground if they’re falling. Clear away furniture, sharp objects, or anything nearby that could cause injury. Turn them gently onto their side with their mouth pointing toward the ground to keep the airway clear.
What you should not do is equally important. Don’t hold the person down or try to restrain their movements. Don’t put anything in their mouth, as this is an old myth that can break teeth or injure the jaw. Don’t give mouth-to-mouth breaths during the seizure, and don’t offer food or water until the person is fully alert. Time the seizure. If it lasts longer than 5 minutes, call 911.
Shock
Medical shock happens when the body isn’t getting enough blood flow to vital organs. It can follow severe bleeding, allergic reactions, infections, or major injuries. Signs include cool and clammy skin, weakness, dizziness or fainting, and changes in behavior like unusual anxiety or agitation.
After calling 911, lay the person down and elevate their legs slightly (unless you think it would cause pain or further injury). Keep them still. Loosen any tight clothing, belts, or collars, and cover them with a blanket to prevent chilling. If the person vomits or starts bleeding from the mouth and you don’t suspect a spinal injury, turn them onto their side to prevent choking.
Poisoning
If someone swallows the wrong medication, too much medication, or a toxic substance, call Poison Help at 1-800-222-1222. This connects you to your local poison control center, where specialists can advise you based on the specific substance, the amount ingested, and the person’s age and weight. Every poisoning is different, so treatment guidance varies widely. Don’t try to induce vomiting unless poison control specifically tells you to.
What to Keep in a First Aid Kit
A well-stocked first aid kit doesn’t need to be elaborate. The national workplace safety standard (ANSI/ISEA Z308.1) provides a good baseline for what belongs in one. A standard kit includes adhesive bandages in assorted sizes, adhesive tape, sterile gauze pads, roller bandages, triangular bandages (which double as slings), scissors, medical exam gloves, antibiotic ointment, antiseptic wipes, a cold pack, burn dressings, an eye covering, eye and skin wash, hand sanitizer, a breathing barrier for CPR, and a first aid guide.
Keep a kit at home, in your car, and at your workplace. Check it every six months to replace anything that’s expired or been used.
Legal Protection When You Help
Every U.S. state has some form of Good Samaritan law designed to protect people who provide emergency first aid in good faith. These laws generally shield you from civil liability as long as a few conditions are met: the situation is a genuine emergency, you act voluntarily (not as part of a job duty), you get the person’s consent before helping (consent is implied if they’re unconscious), you don’t act with gross negligence or reckless disregard, and you don’t request or accept payment.
Ordinary mistakes made while genuinely trying to help are typically protected. What’s not protected is willful misconduct or grossly careless behavior. In practical terms, if you’re acting reasonably and trying to help, the law is on your side.