3 ms·
US Patent 3,419,029 Breathing Valve Assembly HH Straub Dec 31 1968 This appears to be simpler solution that can be AM'd quickly Also, medical staff prefer not
by Metallurgist 7y ago
US Patent 3,419,029 Breathing Valve Assembly
HH Straub Dec 31 1968
This appears to be simpler solution that can be AM'd quickly
Also, medical staff prefer not to use face masks because if the mask does not fit well on to the patients face there is a potential to aspirate body fluids and aerolise the virus.