IFAK Component Deep-Dive: Specs, NSN, and Replacement Criteria

• 12 min reading time

CoTCCC-recommended tourniquet, hemostatic gauze, and vented chest seal specs explained — with NSN numbers, mechanisms of action, and replacement criteria. Everything in a TCCC IFAK, and why the standard exists.

Most IFAK guides tell you what components to buy. This one tells you why those specific components, what they do at the cellular level, and what specs separate the gear that works under load from the gear that fails. If you have ever wondered what makes a CAT Gen 7 different from a $15 windlass tourniquet, or why kaolin matters in hemostatic gauze, this is the reference.

This post is a companion to two earlier guides: What Is an IFAK covers the category overview; The Civilian IFAK covers the buyer's-guide angle. This one goes one level deeper — component specs, mechanisms of action, and the distinguishing technical features.

The MARCH Framework: Why Component Order Matters

Components in a TCCC-compliant IFAK map to the MARCH framework: Massive Hemorrhage, Airway, Respiration, Circulation, Hypothermia. The order is not arbitrary — it reflects the time-to-death sequence for traumatic injury. Massive hemorrhage kills in 3–5 minutes. Airway obstruction kills in 5–10 minutes. Tension pneumothorax can kill in 15–30. Hypothermia is hours but compounds every other priority.

Massive Hemorrhage (M)

Tourniquet — CAT Gen 7

The CAT Gen 7 Combat Application Tourniquet is the CoTCCC-recommended commercial tourniquet, alongside the SOFTT-W. The mechanism: a windlass rod twisted to mechanically compress the limb, occluding arterial blood flow above the wound. Specs that matter:

• Width: 1.5 inches — wide enough to occlude without crushing nerves at minimum effective pressure
• Windlass material: reinforced composite, rated to over 800 lb-force without failure
• Application time: under 30 seconds with training; one-handed self-application is the design baseline
• Indication: arterial bleeding from extremities; place 2–3 inches above the wound, never on a joint
• Combat record: over 4,000 applications since 2005 with documented survival rates above 87% when applied correctly

The CAT and SOFTT-W are the only two windlass tourniquets currently CoTCCC-recommended. Counterfeits, off-brand windlass tourniquets, and strap-only devices without windlass mechanisms fail under arterial pressure. They are not substitutes.

Hemostatic Gauze — QuikClot Combat Gauze

QuikClot Combat Gauze Z-Fold is the CoTCCC-recommended hemostatic dressing, in continuous use across all U.S. military branches since April 2008. Mechanism of action: kaolin (an inert clay mineral) impregnated into the gauze activates Factor XII in the body's intrinsic coagulation cascade, accelerating clot formation without generating heat and without introducing animal or human proteins.

Performance specs:

• Dimensions: 3 inches × 4 yards, Z-folded for rapid wound packing
• Compression time: 3 minutes of sustained direct pressure after packing
• Clotting acceleration: up to 5x faster than plain compressed gauze
• Shelf life: 5 years from manufacture in sealed foil pouch
• NSN: 6510-01-562-3325 (carried by all U.S. military branches)
• X-ray detectable strip built into the gauze for surgical recovery
• Indication: compressible wounds a tourniquet cannot reach — junctional bleeds (groin, axilla, neck), deep extremity wounds, torso wounds with survivable bleeding source

Off-brand gauze without kaolin does not perform the same. The kaolin chemistry is the active ingredient. Verify before purchase. The hemostatics collection covers verified options.

Pressure Dressing — Emergency Trauma Dressing (ETD)

An ETD overwraps wound packing to maintain compression hands-free. Specs that matter:

• Pressure bar: integrated plastic bar that, when reversed, applies and locks direct compression
• Sterile pad: typically 6" x 8" non-adherent pad attached to the elastic wrap
• Self-securing closure: hook or pressure-clip — no separate tape required
• Application time: under 60 seconds for trained users

Airway (A)

Nasopharyngeal Airway (NPA)

The NPA is a soft, flexible tube inserted through a nostril and advanced into the posterior pharynx, holding the tongue clear of the airway in unresponsive casualties. The airway naturally occludes when the tongue falls back — the NPA keeps it open. Specs:

• Adult workhorse size: 28 French (28F)
• Lubricant: water-based packet included; insertion without lubricant causes mucosal damage
• Material: medical-grade soft polymer; rigid NPAs are obsolete and contraindicated
• Indication: unresponsive casualty with respiratory effort but at risk of obstruction; not for conscious patients (triggers gag reflex)

The 28F NPA (4-Pack) covers standard adult sizing and multi-kit stocking.

Respiration (R)

Vented Chest Seals — Paired

Penetrating thoracic trauma creates two simultaneous risks: air entering the chest cavity (pneumothorax) and the wound becoming a one-way valve that builds intrathoracic pressure (tension pneumothorax — fatal in 15–30 minutes). Vented chest seals address both. The one-way silicone valve allows trapped air to escape on exhalation while preventing re-entry on inhalation.

Specs:

• Paired application: always seal both entry and exit wounds; missing the exit wound defeats the intervention
• Adhesive: military-grade hydrogel, designed to bond to bloody and sweaty skin
• Vent design: one-way silicone valve; non-vented seals are no longer the CoTCCC standard for penetrating thoracic trauma
• Shelf life: 5 years from manufacture in sealed pouch
• Indication: any penetrating wound to the torso between the navel and the base of the neck

The HyFin Vented Chest Seal Twin Pack is the TCCC-standard paired seal for kit building.

Circulation (C) and Hypothermia (H)

Mylar Emergency Blanket

Trauma patients lose core temperature aggressively — blood loss reduces metabolic heat production, exposure accelerates conductive loss, and shock impairs thermoregulation. Hypothermia under 35°C compounds bleeding through the lethal triad: hypothermia, acidosis, coagulopathy. Mortality roughly doubles. The Mylar blanket reflects radiant body heat and reduces convective loss. Specs:

• Material: aluminized polyester film, typically 12–20 microns thick
• Folded size: roughly the size of a deck of cards; weighs under 2 oz
• Deployed size: 52" x 84" or larger for full adult coverage
• Indication: deploy on every serious trauma casualty regardless of ambient temperature — the Hypothermia leg of MARCH is not optional

Supporting Tools

Trauma Shears

Blunt-tip stainless steel shears for cutting through clothing, seatbelts, and gear without injuring the patient. The blunt tip is non-negotiable — sharp-tipped scissors lacerate skin under the material being cut. Standard sizing: 7.5 inches with serrated lower blade. Stage at the top of the kit.

Nitrile Gloves

Body Substance Isolation. Latex gloves are obsolete for first response due to allergy risk. Two pair minimum per kit — the first pair is often contaminated or torn during the initial intervention.

Permanent Marker

Tourniquet application time gets written on the casualty's forehead or tourniquet strap in clear digits (e.g. "TQ 14:32"). EMS and trauma surgeons need that timestamp to assess limb viability and determine reperfusion timing. An unknown application time removes critical decision data from the receiving team.

Component Specifications Quick-Reference

Component	Standard / NSN	Shelf Life	Replace After
CAT Gen 7 tourniquet	CoTCCC-recommended	No formal expiration; degrades with use	Any deployment (real or training); visible windlass wear
QuikClot Combat Gauze	NSN 6510-01-562-3325	5 years from manufacture	Expiration date or any pouch damage
Vented chest seal (paired)	CoTCCC-aligned	5 years from manufacture	Expiration date or pouch seal compromised
Pressure dressing (ETD)	FDA Class II	5 years from manufacture	Expiration date
NPA (28F)	FDA Class II	3–5 years from manufacture	Expiration date or lubricant integrity
Mylar blanket	No formal standard	Indefinite if sealed	Visible damage to packaging or material

FAQ

---

Tags

CAT Gen 7 CoTCCC Hemostatic Gauze IFAK Kaolin MARCH NPA NSN Preparedness QuikClot Combat Gauze SOFTT-W TCCC Tourniquet Vented Chest Seals

• Share on:
• WhatsApp
• Deel
• X
• Pin it
• Messenger
• Email

---