Telephone girls learn to carry on as usual in gas masks. Telephone girls are being trained to use special gas masks say that they can remain at their posts in an emergency, even if their switch room is full of gas. The masks are fitted with microphones and earphones so that operators can hear and speak to callers. Yet the masks remain gas proof. Operators are drilled until they can don their mask in less than 10 seconds. Girls who have been through gas chambers declare they could work in the masks without discomfort. Photo shows, girl telephone operators wearing their special gas masks at the switchboard in the Inland Trunk Exchange, Faraday Building.. 3 August 1938