To keep the workplace cooler
By following various ways we can keep the workplace cooler. The basic ideas are to prevent outside heat from coming in and to increase ventilation, as in traditional houses in tropical climates.
The following can help in this :
Retain the evening cool as much as possible by having fresh air in the evening and by considering the building features. In places away from the sea it is much cooler in the evening and morning than in the middle of the day.
Open the windows and doors very wide to increase the natural ventilation.
Avoid floors which retain heat, such as dirt, solid wood and carpets. Increase air circulation beneath the floor.
Design the roof to let the heat escape. The material of the roof and the way it is constructed are particularly important. Good ventilation near the roof makes a vast difference. To avoid direct radiation from the roof, change the material or ceiling underneath. A roof painted in light colours will reflect away the heat from the sun and the sky.
Use light colours for inside walls. Light-coloured surfaces radiate less heat than do dark coloured surfaces. They may also give a psychological impression of coolness.
Make ceilings high. High ceilings are better than low ones.
Install ventilation devices. Artificially induced ventilation for extracting air or pushing air in, is helpful.
Circulate the air by using electric fans.
Barriers should be placed between the heat source and the workers. Some effective heat barriers in the workplace are aluminised reflective partitions, water curtains, and wooden or fabric-covered standing panels.
Hot machines and processes
Hot machines or processes greatly add to the heat stress. The operator must be protected from the heat.
The hot machines or processes should be located outside or at least near the outside so that the heat can escape. Hot surfaces should be insulated by the use of material such as foam or polyester over the metallic surface. This keeps the heat in, saves fuel costs, and reduces the possibility of accidents through contact with the body.
Air-conditioning provides an indoor climate conducive to the health and comfort of people. An air-conditioning system usually simultaneously controls temperature, humidity and cleanliness of the air. Air-conditioning is costly, especially in factories, but it is sometimes a worth-while investment. It is known that air-conditoning increases productivity, helps reduce accidents decreases absenteeism and improves human relations.
To keep the body cool
The heat generated inside the body by physical work adds to the heat coming in from the surrounding. Many people working heavy jobs in front of furnaces and similar equipment have a body temperature reaching 39°C (100F). To cope with the hot temperature, we need to reduce physical workload and secure rest breaks.
It is helpful to learn how to keep the body cool, besides all these technical measures. Heat energy comes from inside the body. There are means to restrict heat gain and facilitate heat loss from the body.
Avoid unnecessarily quick movements. Think out how to do physical work in a less heavy way and with less exposure to hot surroundings; keep out of the direct sunlight. Stand or sit in a place where there is a breeze from open doors or windows or fans. Avoid closed positions where air circulation is restricted. If seated, use a seat in which air can be circulated. Keep away from sources of heat such as hot liquids, machines and fires. Consider whether any barrier can be placed. Never wear any tight clothes or those which prevent evaporation of perspiration. Take cool drinks regularly. Organise a cooler place for rest pauses.
Improving conditions of work and welfare facilities is essential for work in a hot zone. The effects of heat, combined with physical workload, tend to accumulate. Arrangement of working time is particularly important. Avoid long hours of work when heat conditions are particularly severe. Ensure sufficient work breaks. Provide places to cool off away from work; LI ensure a supply of cold drinking water near the workplace. Liquids should be taken in small quantities and often. Provide good washing facilities and access to cleaning of work clothes.
Although cold is not usually a serious problem in the tropical climate, it can occur at high altitudes at night and in the morning in places well away from the sea. The sea and large lakes have a very strong influence in reducing the temperature difference between night and day This is because water absorbs more heat during the day and releases it more slowly at night.
Cold has a great influence on safety, even if the worker is exposed to cold for very short periods. People working with cooled or frozen foods are also exposed to a cold surrounding. The large temperature difference between the cool room and the outside climate is uncomfortable and may be unhealthy. Exposure to cold for short periods of time can produce serious effects, especially when exposed to temperatures below 10° C. The loss of body heat is uncomfortable and quickly affect work efficiency.
Exposure to cold can be reduced by wearing, thick clothing and gloves. In a cold zone, body heat loss is accelerated by air movement. In fact the best protection against cold is to reduce air movement over the skin thus reducing heat loss through convection and evaporation. This can be done by both clothing and protection from the wind.
The hands and feet feel the cold first, then the arms, the legs and finally the rest of the body. The worker will show a lack of co-ordination which reduces the speed and quality of work as well as safety. Bulky clothing can also be dangerous. It interferes with movements and it can easily get caught in the working parts of machines. The same applies to thick gloves. Handling metal or liquids causes the hands to become cold more quickly. Exposure to cold, especially at temperatures below 0° C, may result in frostbite of the fingers, toes, nose and earlobes. This is irritating, painful and dangerous. Damp cold is less pleasant than dry cold. This is mainly because dampness reduces the insulating properties of all clothing except wool.
Heating is less expensive than air conditioning, and well designed clothing can provide protection against almost any climatic conditions. Choice of clothing should take into account the protection from wet and wind and the escape moisture. The body perspires at all temperatures. Waterproof clothing tends to prevent evaporation. The clothing then gets wet from the inside. Adequate protection allows moisture to escape but does not allow rain and wind to penetrate.
Bulky clothes should be avoided as they hamper movement. Hands and feet are particularly susceptible to cold. Older people need more protection against cold than do younger people. Machinery and tasks must be carefully designed to make them less hazardous and easier to perform. Provision of comfortable, heated rest facilities is essential.