A first aid kit is legally required on many vessels and practically required on all of them. Boats operate far from emergency services, in an environment full of sharp hardware, hot surfaces, strong sun, and water that can turn from calm to dangerous in minutes. This guide covers what to carry and how to organize it for quick access when it matters.
Start with a waterproof hard case — Pelican cases or similar dry boxes protect supplies from spray, rain, and submersion. Inside, organize supplies by category using labeled zip-lock bags or a pouch system so you can grab what you need without dumping everything out.
Wound care: Adhesive bandages in multiple sizes, sterile gauze pads, medical tape, butterfly closure strips, antiseptic wipes, antibiotic ointment, and a pair of nitrile gloves. Include a hemostatic gauze or blood-clotting agent for deeper cuts — propeller injuries and filleting knife slips can bleed heavily.
Stabilization: An elastic bandage for sprains, a triangular bandage that doubles as a sling, and a SAM splint (moldable aluminum splint) for suspected fractures. Cold packs are useful for impact injuries.
Medications: Ibuprofen, acetaminophen, antihistamine (diphenhydramine), anti-diarrheal tablets, and a topical hydrocortisone cream for stings and rashes. Add personal prescriptions for anyone aboard who requires them.
Seasickness remedies: Motion sickness affects even experienced boaters in certain conditions. Meclizine (Bonine) or dimenhydrinate (Dramamine) tablets should be in every marine kit. Wristband acupressure bands provide non-drowsy relief for some people.
Sun and heat: Aloe vera gel for sunburn, electrolyte powder packets for heat exhaustion, and a space blanket (mylar) that doubles as a heat casualty shade or hypothermia wrap.
Sting and bite treatment: Vinegar in a small squeeze bottle neutralizes jellyfish stings. Meat tenderizer paste (papain) helps with some marine stings. Tweezers handle splinters, sea urchin spines, and fishhook barb removal.
Hypothermia gear: Even in summer, falling into cold water or being soaked in wind can cause rapid heat loss. A space blanket and hand warmers weigh almost nothing and can be lifesaving.
Include a pair of trauma shears (cuts through clothing, rope, and PFDs), a penlight for checking pupils and illuminating wounds, waterproof matches or a lighter, a whistle, and a small mirror for signaling. A CPR pocket mask is compact and eliminates the biggest barrier to bystander CPR.
For a full breakdown of legally required and recommended safety gear, see our Boat Safety Equipment Guide guide and the Best Boat Safety Kits roundup.
A well-stocked kit is only as useful as the person opening it. Take a basic marine first aid course — the American Red Cross, U.S. Power Squadrons, and many Coast Guard Auxiliary units offer courses specifically tailored to boating injuries and emergencies. Learn how to control bleeding with direct pressure and tourniquets, how to stabilize a suspected spinal injury in the water, and how to recognize and treat heat-related illness. Practice CPR annually — the skills fade faster than most people realize, and a refresher takes less than an hour.
Designate a first aid officer on board. This person knows where the kit is, what is in it, and how to use every item. On boats with multiple regular passengers, rotate the role so everyone builds competence. In a real emergency, the trained person may be the injured person — having backup knowledge saves lives.
A basic kit is a starting point, but marine environments create injuries that standard kits are not equipped for — fishhook removal, jellyfish stings, sun-related illness, and hypothermia. Supplement a standard kit with marine-specific additions.
Check expiration dates on medications and ointments at the start of each season. Replace anything used, expired, or showing signs of water damage. Adhesive bandages lose their stick after prolonged exposure to humidity.
Absolutely. The best-stocked kit in the world is useless if you do not know how to use it. The American Red Cross and many boating safety organizations offer courses specifically tailored to marine first aid.