An elaborate ergonomic questionnaire was applied on 300 personnel working in shifts in different health care units of West Bengal. Physiological responses and psycho-physiological responses were studied on ten subjects to evaluate work stress and job demands in different shifts. It was observed that although on-job sleep facilities were available during night shift in some health care units, a large number of personnel complained about sleeplessness and nonadaption to the night-shift schedule. The scores obtained from the answers to the questionnaire revealed that only a few (13%) of the personnel were of the 'Evening' type, whose complaints about different health problems are much less. They tended to adjust to the night work quickly from the change of day or afternoon shifts.