Table 1.

Shift type and working times of study participants (n=488).

Type of work	Type of activitya	Sector	Shift type	Work hours	n
Factory	Moderate	Electrical testing and packing	Rotating	14:00–23:00 h	70
				06:00–15:00 h
				22:00–07:00 h
Factory	Moderate	Production	Rotating	06:00–18:00 h	10
				18:00–06:00 h
Factory	Moderate	Maintenance	Rotating	08:00–20:00 h	11
				20:00–08:00 h
Factory	Low	Administrative	Day	08:00–18:00 h	46
Factory	Moderate	Cleaning	Rotating	06:00–14:00 h	11
				14:00–22:00 h
Rubber tapper	High	Extractivism	Day	05:00–17:00 h	340

^aClassification by metabolic rate according to Brazilian Bylaws no 15 (BRASIL, 1978).