A person working at a high pace or in a very hot environment loses water and salt through sweat. This loss should be made up by having the worker consume more water and salt. Fluid intake should equal fluid loss; in other words, what goes out must come in. On average, about one litre of water each hour may be required to replace the fluid loss. Plenty of cool (10-15°C) drinking water should be available on the job site and workers should be encouraged to drink water every 15 to 20 minutes even if they do not feel thirsty.

Many people opt for sport drinks, fruit juice, etc. Drinks specially designed to replace body fluids and electrolytes may be taken but for most people, they should be used in moderation. They may be of benefit for workers who have very physically active occupations but keep in mind they may add unnecessary sugar or salt to your diet. Fruit juice or sport and electrolyte drinks, diluted to half the strength with water, is an option. Drinks with alcohol or caffeine should never be taken, as they dehydrate the body. For most people, water is the most efficient fluid for re-hydration.

A worker used to, or acclimatized to, lifting heavy loads or working in the heat sweats more “efficiently” – they sweat sooner and sweat more, but they lose less salt in their sweat than labourers who are not used to such work. For this reason, the salt in a normal diet is usually enough to maintain the electrolyte balance ­ and keep the body working well. For un-acclimatized workers who are not used to manual labour or working in the heat, and who will therefore lose more salt in their sweat, they may wish to use extra salt in food. Salt tablets are not a good idea, however, because the salt does not enter the body system as fast as water or other fluids. Too much salt can cause higher body temperatures and can also make someone feel thirsty or sick. Workers on salt-restricted diets should talk to their doctor about how much salt they need for their job.