Explained

First Aid Kits, Explained

After reading, you'll understand what Class A and Class B actually require, what the container Types mean, why piece counts are noise, and where trauma gear fits.

Updated August 23, 2026 · Companion to our Health & Wellness review

In this guide

The 30-second version
The products
What actually matters
Specs in plain English
Green flags vs red flags
The brands
How to read a listing
How much to spend
FAQ

First-time buyers get tripped up by a number. Kits are sold on piece count, the counts run into the hundreds, and it feels obvious that more must be better. It is not, because nothing defines what a piece is, and one adhesive bandage counts the same as one tourniquet. There is a real list, published as a workplace standard, and once you know it exists the whole category reorganises itself into kits that name a class and kits that do not.

The 30-second version

The class letter is the whole signal, because Class A and Class B name every required item, quantity and minimum size, and a piece count names none of them.
The Type is about the container, so a Type IV waterproof case is not a better kit than a Type I cabinet holding the same class of contents.
OSHA does not mandate a kit, it requires adequate first aid supplies to be readily available, and its own appendix pointing at the standard is explicitly non-mandatory.
Trauma gear is a separate package, since the standard puts tourniquets, hemostatic bandages and chest seals in a bleeding control kit rather than in a Class A first aid kit.
A kit is compliant as sold, and the required label says exactly that, which is why the inspection interval matters as much as the purchase.

The products this guide is about

Our verdict on each, with the full reasoning on the companion review.

What actually matters

Class A vs Class B - Class A is the baseline for cuts, abrasions, minor burns and eye injuries; Class B is for higher risk workplaces and adds a splint and a tourniquet on top of larger quantities of everything else. Choosing between them is a hazard question about your space rather than a budget question.
Edition year - the current edition is ANSI/ISEA Z308.1-2021, effective 15 October 2022, and older 2015 labelled stock is still on sale. The 2021 changes are specific: a foil blanket became mandatory in both classes, hand sanitizer quantities rose, and the tourniquet definition tightened to an arterial device using a windlass or ratchet.
Container Type - Types I to IV describe portability, mountability and water resistance, and only Type IV must pass performance tests for salt fog corrosion and impact. Pick the Type from where the kit will live, then pick the class from what could happen there.
Minimum fill - the standard's quantities are minimums rather than targets, and larger items that meet the performance requirements count as equivalent. A compliant kit can exceed the fill in any direction and still be compliant, which is why some good kits carry far more than the table asks.
The compliance label - a compliant kit must carry a legible, permanent label naming the edition, class and type and printing the required minimum fill. That label is a manufacturer self-declaration rather than a third-party certification, so read it as a specific claim you can check yourself.
Maintenance - the same label says any supply past its marked expiry should be discarded and replaced, and ISEA recommends inspection at least monthly or after any incident where something was used. Refill packs are the intended way to do this, and they cost far less than a new kit.
Bleeding control - severe external bleeding is handled by a separately packaged kit whose essential contents the standard lists as a chest seal, a compression bandage, hemostatic bandages, a thermal blanket and a tourniquet. Buying that separately is the correct move rather than a workaround.

The specs, in plain English

ANSI/ISEA Z308.1-2021The American National Standard for minimum requirements for workplace first aid kits and supplies, published by the International Safety Equipment Association. ANSI approved it in April 2022 and it took effect on 15 October 2022, and ISEA describes it as the fifth revision since the standard first appeared in 1978. It is a voluntary consensus standard, not a law.

Class AThe baseline kit, intended for the most common workplace injuries: major wounds, cuts and abrasions, minor burns and eye injuries. Its required fill is 19 item types adding up to roughly 74 pieces, including 16 adhesive bandages, a CPR breathing barrier, a foil blanket, an eyewash and a triangular bandage. It requires no tourniquet and no splint.

Class BThe kit for more populated, complex or high risk environments. It requires everything Class A does in larger quantities, roughly 202 pieces in total, plus two item types Class A does not carry: a padded splint at least 4 by 24 inches and an arterial tourniquet. OSHA's 2019 letter of interpretation strongly recommends Class B for construction, shipyards and industries where amputations are likely.

Container Type I to IVA rating for the box rather than the contents. Type I mounts in a fixed indoor position and is not really portable, which describes most wall cabinets. Type II is portable and indoor. Type III is portable and mountable for indoor and sheltered outdoor use and must have a water resistant seal. Type IV is portable, mountable and waterproof, and must survive 480 hours of salt fog plus corner drops from four feet after hot and cold conditioning.

Minimum fillThe table of items and quantities a kit must contain to claim a class, reprinted on the kit's own label. It is a floor, not a recipe: larger items that meet the performance requirements count as equivalent, and employers are expected to add supplies for their own hazards. A kit that has been raided and not restocked is no longer at minimum fill.

Unitized kitA kit whose supplies are packed in uniform, colour coded boxes so restocking means dropping in a replacement box. The standard's appendix sets the colours: blue for antiseptics, yellow for bandages, red for burn treatment, orange for personal protective equipment and green for miscellaneous. Kits described as 16 unit or 24 unit are sized by how many of these boxes they hold.

Person ratingThe 10 person, 25 person or 50 person label on a workplace kit describes the quantity of supplies rather than a headcount limit. It is a purchasing convenience and is not part of the class definition. For a household it mostly tells you how much will expire unused.

Trauma pad vs sterile padA sterile pad is a small dressing, at least 3 by 3 inches under the standard, for covering a modest wound. A trauma pad is bigger, at least 5 by 9 inches, and is what you press onto something that is bleeding hard. Class A requires two of each and Class B requires four of each.

Bleeding control kitA separately packaged set for treating life-threatening external bleeding immediately, covered by guidance in the 2021 standard rather than by the Class A or Class B fill. The essential items listed are a chest seal, a compression bandage, hemostatic bandages, a thermal blanket and a tourniquet, with gloves, shears and a permanent marker alongside. The standard says the package should be distinctive so a responder can grab it fast.

Green flags vs red flags

Green flags

The case or listing prints a class letter, a Type numeral and the edition year, in the form ANSI/ISEA Z308.1-2021, Class A, Type III.
The maker publishes the contents item by item with quantities, so you can check them against the class table before buying.
A matching refill pack exists for the same kit, which means restocking is far cheaper and faster than replacing the case.
The kit contains the unglamorous required items that budget kits omit: a CPR breathing barrier, an eyewash, a foil blanket, a triangular bandage and a gel soaked burn dressing.
The Type matches where the kit will actually live, with Type III or IV for anything mounted outdoors, in a vehicle or on a boat.

Red flags

The headline is a piece count and the words class and Z308.1 appear nowhere on the page.
The listing claims it meets OSHA but the spec table says Not Compliant under ANSI, or says ANSI approved with no class letter and no edition year, which is not something the standard provides for.
The label names the 2015 edition, which predates the mandatory foil blanket, the higher hand sanitizer counts and the tighter tourniquet definition.
A very large share of the contents is adhesive bandages in several sizes, which inflates the count without adding capability.
A tourniquet is included but described only as a band or a strap, with no windlass or ratchet, which the 2021 edition specifically distinguishes from a blood draw band.

Who's who: the brands

First Aid Only - An Acme United brand running two clearly separate lines: workplace kits and cabinets that print the class, type and edition on the case, and consumer kits sold on piece count that name no standard at all.
North American Rescue - A trauma equipment maker best known for the Combat Application Tourniquet, whose workplace kits are the ones here that state a Z308.1 class and then add bleeding control gear on top of it.
My Medic - A direct-to-consumer maker of soft, trauma-forward kits built around tourniquets and MOLLE mounting, sold with a training course and a modular refill system rather than an ANSI class.
Adventure Medical Kits - Long-established wilderness and marine kits organised around group size and trip length rather than a workplace class, with waterproof inner bags inside a water-resistant outer.
Certified Safety Manufacturing - A long-running US manufacturer of industrial first aid kits and cabinets sold in Class A and Class B configurations, mostly through safety distributors rather than direct.

How to read a listing without getting fooled

Start at the bottom of the listing rather than the top. Ignore the piece count entirely and look for three tokens: an edition year, a class letter and a Type numeral. If all three are there, pull up the class table and read the maker's contents list against it line by line, paying particular attention to the items that are easiest to leave out, which are the CPR breathing barrier, the eyewash, the foil blanket, the triangular bandage and the gel soaked burn dressing. If the three tokens are missing, you are not looking at a checkable claim, so judge the kit purely on its published contents, and if the contents are not published item by item then there is nothing to judge. Then sanity check the Type against reality: a kit hanging in a hallway needs no more than Type I or II, a kit going in a van or on an outside wall wants Type III, and only a kit that will get properly wet needs Type IV.

How much should you spend?

Budget tier buys either a small soft consumer kit sold on piece count or a genuinely compliant Class A kit in a plain plastic case, and the second is by far the better use of the money. Mid-range buys a Class B kit with a tourniquet and a splint already inside, or a larger weatherproof Class A kit for a vehicle or a jobsite, and this is where case quality and mounting hardware start to matter. Premium is mostly trauma-forward kits that pair a compliant fill with a tourniquet, a chest seal and a hemostatic dressing, or soft direct-to-consumer kits where you are paying for the carrying system and the individual item quality rather than a class rating. Refill packs sit well below whole-kit outlay in every tier, so budget for restocking rather than replacing.

Questions, answered

Is an ANSI compliant kit certified by anyone?

No. The standard requires the manufacturer to print a permanent label naming the edition, the class and the type and listing the required minimum fill, and that label is a self-declaration. There is no third-party test house stamping first aid kits the way there is for some other safety equipment. What the label buys you is specificity: a claim precise enough that you can check it against a published table yourself.

How many kits do I need, and where should they go?

The standard's guidance points at response time rather than headcount, and so does OSHA. OSHA has long interpreted near proximity for serious injuries to mean emergency care available within three to four minutes, with up to fifteen minutes acceptable in low risk settings such as offices. Applied at home that means one kit where the sharp and hot things are, usually the kitchen or the workshop, and a second in the car, rather than one large kit in an upstairs cupboard.

My kit says Z308.1-2015. Do I have to replace it?

Not necessarily. The gap between the 2015 and 2021 fills is small and specific: a foil blanket is now required in both classes, hand sanitizer went from six to ten packets in Class A and from ten to twenty in Class B, and the Class B tourniquet must now be an arterial device using a windlass or a ratchet rather than merely being an inch wide. Several makers sell conversion packs that supply the missing items plus new labels for exactly this reason, and that is cheaper than buying a new kit.

What does a household kit need that the workplace standard does not require?

The Red Cross publishes a recommended list for a family of four that overlaps heavily with Class A but adds a few things the workplace list leaves out, including two packets of 81 mg aspirin for a suspected heart attack, two hydrocortisone packets, an oral thermometer and tweezers. The standard's own appendix treats items like low dose aspirin, antihistamines, analgesics and hydrocortisone as supplements to be added according to the hazards you actually face. Add your own regular medications and, if anyone in the house carries an allergy plan, that too.

Ready to choose? See our top pick, the alternatives, and the one we'd skip See the First Aid Kits verdicts