ABSENTEEISM among the workers of the Sorocabana Railroad in the department of the electric punch card machines was so high, as compared with that in other departments, that it demanded the attention of a neuropsychiatrist. He presented the following report: "... the patients complain mostly of nervous irritability, lessened capacity for work, palpitation and sleeplessness. They are persons who are maladjusted in their private lives and whose neurotic symptoms show up with nervous fatigue brought about by the continuous noise of the machines. Such employees cannot receive compensation. All the patients but one returned to work after treatment and a varying period of rest."
The matter was therefore referred to the department of otology at the Sorocabana Railroad medical service, where it was approached by the study of the room noise and its influence on the workers' ears. This investigation was undertaken from three standpoints: (1) study of the room
de ALMEIDA HR. INFLUENCE OF ELECTRIC PUNCH CARD MACHINES ON THE HUMAN EAR. Arch Otolaryngol. 1950;51(2):215–222. doi:10.1001/archotol.1950.00700020236007