Breathing masks are essential protective devices designed to filter air or supply oxygen by covering the nose and mouth, serving as vital barriers against airborne pathogens and toxic environments. Ranging from disposable N95 respirators to specialized medical oxygen masks and industrial Self-Contained Breathing Apparatus (SCBA), these devices are selected based on the specific need for filtration, oxygen delivery, or atmosphere supply. Understanding the distinction between filtering contaminants and supplying breathable air is key to selecting the appropriate respiratory protection.

Chest seal
What Is a Chest Seal? A chest seal is a sterile, occlusive (airtight) adhesive dressing applied over a penetrating chest wound to prevent air from entering the pleural space—the thin, fluid-filled cavity between the lungs and the chest wall. When a penetrating object (such as a bullet or a knife) breaches the chest wall, it bypasses the body’s natural airway (the trachea). As the patient inhales, air enters directly into the pleural cavity rather than into the lungs. This condition, known as a pneumothorax (collapsed lung), prevents the lung from expanding and oxygenating the blood. Without intervention, it can rapidly progress to a tension pneumothorax, which is a life-threatening condition where trapped air builds up such high pressure that it pushes the heart to one side and collapses the remaining lung. This can lead to cardiac arrest and death in minutes. The Asherman Chest Seal, introduced in 1974, was the first widely adopted medical device for this purpose. Does It Stop Bleeding? No. A chest seal does not stop bleeding. Its sole function is to create an airtight barrier so that the patient can breathe normally. A sucking chest wound requires concurrent efforts to control external hemorrhage (with direct pressure
