Blackett's Aerophor was an early closed-circuit breathing apparatus primarily designed for mine rescue operations, developed in the years leading up to World War I. Named after its inventor, Guy Blackett, a mining engineer, it represented a significant advancement in self-contained breathing technology.
Developed in collaboration with Siebe Gorman & Co. Ltd., a prominent manufacturer of diving and breathing equipment, the Aerophor system utilized compressed oxygen from a cylinder and a chemical absorbent (typically caustic soda or slaked lime) to remove carbon dioxide from the exhaled breath. This closed-circuit design meant that the wearer's exhaled air was re-breathed after purification, conserving the oxygen supply and allowing for extended operational times in environments contaminated by toxic gases or lacking oxygen.
The Aerophor was comparatively lighter and more compact than some contemporary open-circuit or early closed-circuit devices, contributing to its adoption by rescue brigades in coal mines, particularly after the devastating mine disasters of the early 20th century highlighted the urgent need for effective rescue equipment. Its introduction played a role in improving the safety and efficacy of mine rescue efforts during a critical period in industrial history.