Implementation of preventive measures and Standard Operating Procedures (SOPs) early
in the operations so that sound work practices are developed and followed,
Proper initial training of workers to recognize the symptoms of temperature extreme
related disorders or conditions in themselves and their fellow workers,
Implementation of a "buddy system", and
Proper acclimatization of all workers to new or changing work conditions.
6.2. HEAT STRESS
Increased physical demands on workers occur as a result of increased air temperature and
humidity. Wearing PPE also increases the demands on workers, due to:
Added weight of the equipment,
Loss of the body's natural cooling processes,
Increased energy consumption by the body, and
Lack of sufficient fluid replenishment.
Other factors that influence the occurrence of heat related disorders or conditions include
environmental conditions, clothing, workload, and the individual characteristics of workers.
Workers should be pre-screened prior to beginning operations. Once baseline values are
obtained, they can be used to effectively assess the health of workers during and immediately
after operations (e.g., pulse, blood pressure, body temperature, body weight).
Because of the variability of these factors and the compounding effect that each may have on an
individual's health, a physiological monitoring program should be established.
Personnel who are not required to wear PPE are not immune to the potential hazards of heat
related disorders or conditions and should be included in the monitoring program.
The guidance for workers wearing permeable clothing is specified in the current version of the
American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold Limit Values
for Heat Stress. If actual clothing differs from the ACGIH standard ensemble in insulation value
and/or wind and vapor permeability, changes should be made to the monitoring requirements and
work rest period to account for these differences. Table 6-1 provides the suggested frequency of
physiological monitoring for fit and acclimatized workers.
The ACGIH TLV guide contains a separate table for workers wearing semipermeable and
impermeable encapsulating clothing. In these situations, refer to this table.