Telephone communications with several commercial respirators

Previous work showed that telephone communications while wearing military r espirators degraded both word comprehension and recognition speed. In addit ion, electronic amplification of the speech diaphragm signal had shown no a dvantage to the extra hardware. This experiment was performed to test effec ts of different configurations of commercially available respirators on tel ephone communications accuracy and speed. Twelve pairs of subjects were sep arated into different rooms and communicated by telephone. Modified rhyme-t est words were presented by computer to the speaker, who transmitted the wo rd by telephone to the listener. During the first replication, subjects wer e given no instruction about telephone communications procedure. During the second replication subjects followed a communications protocol that instru cted them when to move the telephone handset from their ears to their mouth s. Results showed that the protocol uniformly improved communications accur acy without incurring any extra time penalty, Word comprehension was still twice as fast without a respirator as with a respirator. Accuracy with the protocol nearly equaled the no respirator control value for most respirator s tested.