How a Chest Seal Works
A penetrating chest wound can open a path for air to enter the pleural space from outside. As that air accumulates, it collapses the lung and — if pressure keeps building — pushes the mediastinum across, choking off venous return in a tension pneumothorax. A chest seal is an occlusive dressing that closes the hole so the lung can work, while a vented design gives trapped air a one-way path out.
Vented vs. non-vented
| Type | How it works | Note |
|---|---|---|
| Vented | One-way valve or channels let air escape but not re-enter | CoTCCC-recommended; lowers tension-pneumothorax risk |
| Non-vented | Fully occlusive; requires manual "burping" if pressure builds | Acceptable when a vented seal isn't available |
Application doctrine
- Expose and dry — wipe the skin so the seal adheres; blood and sweat defeat the adhesive.
- Seal entry and exit — a through-and-through wound needs a seal on both sides.
- Watch for tension — rising distress means lift or "burp" a non-vented seal, or confirm the vent is clear.
- Carry two — most penetrating chest wounds warrant more than one seal.
Stocking for penetrating trauma? Carry vented seals in pairs alongside hemorrhage control. Anchor your loadout with the trauma-response brief.
Frequently Asked Questions
What is a chest seal used for?
It closes an open chest wound so air can't enter the chest cavity from outside and collapse the lung. Vented seals also let trapped air escape, reducing the chance of a tension pneumothorax.
What is the difference between a vented and non-vented chest seal?
A vented seal has a one-way valve or channels that let air out but not back in; a non-vented seal is fully occlusive and must be lifted or burped if pressure builds. CoTCCC recommends vented designs.
Do I need to seal both sides of a chest wound?
Yes, if the wound is through-and-through. A gunshot or penetrating injury with an exit wound needs a seal over both the entry and the exit, which is why kits commonly carry two.
How do you burp a chest seal?
If a casualty with a non-vented seal develops rising breathing difficulty, lift one edge of the seal briefly to let trapped air escape, then reseal. A vented seal is designed to do this automatically.
Will a chest seal stick to bloody skin?
Adhesion is the weak point. Wipe the skin as dry as possible before applying, and press firmly around the whole edge. Carry a backup, since blood and sweat can defeat the adhesive.
Related collections
MED-TAC International Corp. is a clinician-founded, veteran-led tactical medicine provider. Product references to CoTCCC reflect committee recommendations and do not imply FDA approval or certification. This content is educational and is not a substitute for hands-on training or medical direction.