In the comprehensive world of emergency medical equipment, there is perhaps no piece of equipment more critically required than the respiratory mask.
Also known as an oxygen mask, respiratory masks come in various shapes and sizes, from basic cannulae to reservoir masks used to provide oxygen quickly in critical hypoxia situations.
However, much like other vital emergency supplies, it was not initially designed with medical use in mind, but instead to make the pioneering world of aviation safer as pilots started to ascend ever closer to the heavens.
What Is A Respiratory Mask?
A respiratory mask or oxygen mask is an adjustable device made from a combination of rubber, silicone or plastic that is placed over the nose and mouth (or occasionally the entire face) and allows oxygen to be supplied to the lungs through a supplementary tank or alternative supply.
It is typically necessary in cases where air with a higher level of oxygen than the 20.9 per cent typically found in air is required. Some masks can provide over 70 per cent oxygen.
These are typically used with someone with severe hypoxia, or a lack of oxygen that is causing damage to the body’s vital organs.
Why Was The Respiratory Mask Invented?
One of the biggest environmental causes of hypoxia is altitude sickness, when you travel high enough above sea level that the level of oxygen in the air is insufficient to sustain normal function, and the cells are starved of oxygen.
It is typically found either in flight or when travelling over 2,500 metres above sea level. Over 8,000 metres above sea level is known as the “death zone”, where the body uses more oxygen than it can be replenished, typically within a matter of hours.
Early aviators had the same problem in aircraft which did not have closed cockpits, so in 1919, a pioneering early oxygen mask was developed and written about in the magazine Popular Science.
It used a multi-stage warming procedure in order to ensure that the oxygen gas used would not be so cold as to destroy the lungs through frostbite.
When Were Respiratory Masks Used As Medical Equipment?
However, whilst these systems worked, they were ill-suited for both medical and aviation purposes, as they relied on ill-fitting tubes or masks which could freeze over, removing this vital supply of oxygen, causing hypoxia, pilot error and crashes.
The solution was the Boothby-Lovelace-Bulbulian (BLB) mask, the first recognisably modern medical mask pioneered by Walter Boothby, W. Randolph Lovelace II and Arthur Bulbulian.
Because it covered the nose and mouth securely, it could more easily be depended upon for medical purposes, and adjustments for military use made it the early standard for fighter pilot masks for the United States Air Force in 1941.
Before this, it was also supplied to the Royal Air Force, who used it during the Battle of Britain in 1940.
Whilst this system has since been replaced by other models that greatly iterated and improved on the original BLB mask’s design, the system remains historically important and shapes what has become a life-saving piece of emergency equipment.