Safe Work Practices > Hot Environment

Date Reviewed: February 21, 2023

Employees will be allowed to leave a hot work area to a cooler place, reduce their pace, and remove or loosen clothing (when and where safe to do so) if they are feeling any symptoms of heat stress.

A. Purpose of this practice

The purpose of this practice is to protect workers from heat stress and its health risks. These practices must be followed at all times.

B. Responsibility

Employees working in hot environments will be trained in the purpose and use of these practices. This training will be received by all employees (new, transferred and current). Visitors to the site will also be instructed about hot environment practices.

C. Hot Environment Practices

(1) Identify the 4 environmental factors that cause heat stress on the body.

•temperature

•humidity

•radiant heat

•air velocity

(2) Identify the personal characteristic that increase heat stress on the body.

•age

•weight

•fitness

•medical condition

•acclimatization to the heat

(3) Identify signs of heat release.

•blood circulation to the skin

•sweating

(4) Steps to releasing heat stress.

•moving to a cooler place

•reducing work pace or load

•removing or loosening some clothing

(5) Identify the signs of the body storing heat.

•body’s core temperature raises

•heart rate increases

•lost concentration

•difficulty focusing on a task

•becomes irritable and sick

•loses the desire to drink

•fainting

•death

(6) Remove yourself or any other personnel from the job site that are exhibiting any of the above symptoms.

(7) Identify the different heat disorders.

Heat stroke is the most serious health problem for workers in hot environments. It is caused by the failure of the body to regulate its core temperature.

•Signs:

▪sweating stops

▪body can no longer rid itself of excess heat

▪mental confusion, delirium, loss of consciousness, convulsions or coma

▪a body temperature of 106 F or higher; and

▪hot dry skin which may be red, mottled, or bluish

•Treatment:

▪treat promptly or victim may die

▪call for medical help

▪while waiting for medical help the victim must be removed immediately to a cool area

▪his or her clothing soaked with cool water

▪he or she should be fanned vigorously to increase cooling

Heat exhaustion is the result of loss of fluid through sweating when a worker has failed to drink enough fluids or take in enough salt or both.

•Signs:

▪still sweats

▪experiences extreme weakness or fatigue, giddiness, nausea, or headache

▪skin is clammy and moist, the complexion pale or flushed

▪body temperature normal or slightly higher

•Treatment:

▪victim should rest in a cool place and drink salted liquids

▪severe cases: victims who vomit or lose consciousness may require longer treatment under medical supervision.

Heat cramps are painful spasms of the bone muscles and are caused when workers drink large quantities of water but fail to replace their bodies' salt loss. Tired muscles are usually the one most susceptible to cramps.

•Treatment:

▪taking salted liquids by mouth or saline solutions intravenously for quicker relief, if medically determined to be required

Workers who simply stand still in the heat can still faint and be effected by the heat because they may not be acclimatized to a hot environment.

•Treatment:

▪brief period of lying down

▪moving around, rather than standing still, usually reduces the possibility of fainting

Heat rash (prickly heat) may occur in hot and humid environments where sweat does not easily evaporate from the skin. The rash can impede a worker’s performance because of the extensiveness of it or infection and can even result in temporary total disability.

•Prevention:

▪resting in a cool place and allowing the skin to dry

(8) Preventing heat stress.

Acclimatization to the heat through short exposures followed by longer periods of work in the hot environment can reduce heat stress.

Engineering controls including general ventilation and spot cooling at points of high heat production may be helpful.

•Other ways of prevention:

▪shielding (radiant heat sources)

▪evaporative cooling and mechanical refrigeration

▪cooling fans

▪eliminating steam leaks will also help

▪equipment modifications (power tools to reduce manual labour)

▪personal cooling devices or protective clothing

(9) Acclimatization for new workers and those returning from two week absences and making plenty of drinking water available at the workplace can help reduce the risk of heat disorders. Trained first aid workers to recognize and treat heat stress disorders and making the names of trained staff known to all workers is essential.

(10) Alternating work and rest periods with longer rest periods in a cool area can help workers avoid heat strain. Heavy work should be scheduled during the cooler parts of the day and appropriate protective clothing provided. Supervisors trained to detect early signs of heat strain and permitting workers to interrupt their work if they are extremely uncomfortable.

(11) Educate employees, so workers are aware of the need to replace fluids and salt lost through sweat and recognize dehydration, exhaustion, fainting, heat cramps, salt deficiency, heat exhaustion, and heat stroke as heat disorders.