1026 Int Diploma IB10 v2
March 25, 2017 | Author: farhat ali | Category: N/A
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Element IB10: Work Environment Risks and Controls
Element IB10: Work Environment Risks and Controls
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Element IB10: Work Environment Risks and Controls
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Element IB10: Work Environment Risks and Controls
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Element IB10: Work Environment Risks and Controls
Contents Introduction General Requirements
Extremes of Hot and Cold Health Effects of Exposure to Extreme Temperatures Measurement of the Thermal Environment Control
Lighting Types of Lighting Hazards Associated with Lighting Measurement of Illuminance
Welfare Facilities Sanitary Conveniences Washing Faciliti Facilities es Drinking Water Clothing Accommodation Facilities for Changing Clothing Rest and Eating Facilities Disabled Persons
First Aid
5 5 8 8 14 20 22 22 24 26 28 28 29 29 30 30 31 31
Introduction Assessment of First-Aid First-Aid Requirements Requirements
32 32 33
References
36
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Element IB10: Work Environment Risks and Controls
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Element IB10: Work Environment Risks and Controls
Introduction This Element will explain the requirements relating to the workplace environment plus providing further information regarding the details and the provision of rst-aid cover.
General Requirements Employers should ensure that every workplace, modication, extension or conversion which is under his control and where any of his employees work, complies with the foll owing requirements. People other than employers also have duties if t hey have control, to any extent, of a workplace, e.g. owners and landlords (of business premises) should ensure that common parts, common facilities, common services and means of access within their control, comply. Tenant employers are responsible for ensuring that the workplace which they control complies, and that facilities, particularly welfare provisions, are provided. Where a workplace is in a building, the building should have a stability and solidity appropriate to the nature of the use of the workplace.
Maintenance The workplace, and equipment and devices, should be maintained in an efcient state, in efcient working order and in good repair. ‘Efcient’ in this context means efcient from the view of health, safety and welfare (not productivity or economy). The frequency of regular maintenance, and precisely what it involves, will depend on the equipment or device concerned. The likelihood of defects developing, and the foreseeable consequences, are highly relevant. The age and condition of equipment, how it is used and how often it is used should also be taken into account. Sources of advice include published ILO guidance, and EU standards and other authoritative guidance, manufacturers’ information and instructions.
Ventilation Effective and suitable provision should be made to ensure that every enclosed workplace is ventilated by a sufcient quantity of fresh or puried air. Enclosed workplaces should be sufciently well ventilated so that stale air, and air which is hot or humid because of the processes or equipment in the workplace, is replaced at a reasonable rate. In many cases, windows or other openings will provide sufcient ventilation in some or all parts of the workplace. Where necessary, mechanical ventilation sys tems should be provided for parts or all of the workplace, as appropriate. This section covers general workplace ventilation and not Local Exhaust Ventilation (LEV) which is covered in Element B3. In the case of mechanical ventilation systems which re-circulate air, including air-conditioning systems, re-circulated air should be adequately ltered to remove impurities. Ventilation systems should be subject to a suitable system of maintenance. Where necessary for reasons of health and safety, mechanical ventilation systems should include an effective device to give visible or audible warning of any failure. This will not apply in most workplaces. It will, however, apply to ‘dilution ventilation’ systems used to reduce concentrations of dust or fumes in the atmosphere and to any other situation where a breakdown in the ventilation system would be likely to result in harm to workers. Workers should not be subject to uncomfortable draughts. In the case of mechanical ventilation systems it may be necessary to control the direction or velocity of air ow. Workstations should be re-sited or screened if necessary.
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Element IB10: Work Environment Risks and Controls
Temperature in Indoor Workplaces The temperature in workrooms should provide reasonable comfort without the need for special clothing. Where such a temperature is impractical because of hot or cold processes, all reasonable steps should be taken to achieve a temperature that is as close as possible to comfortable. Excessive effects of sunlight on temperature should also be avoided. Methods of heating or cooling which results in the escape into a workplace of fumes, gas or vapour of such character and to such extent that they are likely to be injurious or offensive to any person should not be used, e.g. xed heating systems should be installed and maintained in such a way that the products of combustion do not enter the workplace. Where the temperature in a workroom would otherwise be uncomfortably high, e.g. because of hot processes or the design of the building, all reasonable steps should be taken to achieve a reasonably comfortable temperature. Where a reasonably comfortable temperature cannot be achieved throughout a workroom, local heating or cooling (as appropriate) should be provided. Sufcient thermometers should be provided. Workplaces should be adequately thermally insulated where necessary, having regard to the type of work carried out and the physical activity of the persons carrying out the work, and excessive effects of sunlight on temperature should be avoided.
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Element IB10: Work Environment Risks and Controls
Thermal Comfort – Workplace Design Thermal comfort is very difcult to dene, normally because a range of environmental and personal factors need to be taken into account when deciding on the temperatures and ventilation that will make the employees feel comfortable. The most that can realistically be achieved is a thermal environment that satises the majority of the employees. The most effective way of ensuring thermal comfort is to design the workplace appropriately. A number of issues can be addressed as follows: ▪
Heating: Many types of heating are available, such as hot air heated by gas or oil burners, central heating by steam heat circulated through radiators, combined heating and ventilating systems where the air-conditioning system is used to heat air which is then circulated, electric heaters, oor heating or overhead radiant heating from gas or electric;
▪
Air movement: Small personal fans can provide a refreshing movement of air on the face and larger oscillating fans can provide a swirling air movement, although some people nd this ‘draughty’. Large diameter fans suspended from the ceiling can provide a swirling air movement that is effective over wide areas. Exhaust fans mounted in the roofs and walls are useful for removing heated air, however, whilst improving general air movement they may have little effect on thermal comfort;
▪
Air-conditioning: This can range from small units that lower the air temperature but do not control humidity levels or air movement, to large units that can cope with extreme conditions, and also control humidity and air movement;
▪
Evaporative cooling: These produce a moderate reduction in air temperature and increase humidity. They operate by passing hot air over water-saturated pads and the water evaporation effect reduces the dry–bulb temperature; and
▪
Thermal insulation: There are many different types of thermal insulation materials such as loose lls, foams, rock wool and boards. The material acts as a barrier that retards heat ow in the summer and heat loss in the winter. It is only effective where there is a temperature difference between the inside and the outside of the building or between two areas inside a building.
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Element IB10: Work Environment Risks and Controls
Extremes of Hot and Cold Health Effects of Exposure to Extreme Temperatures Heat The body reacts to heat by increasing the blood ow to the skin’s surface, and by sweating. This results in cooling as sweat evaporates from the body’s surface and heat is carried to the surface of the body from within by the increased blood ow. Heat can also be lost by radiation and convection from the body’s surface. Typical symptoms include: ▪
An inability to concentrate;
▪
Muscle cramps;
▪
Heat rash;
▪
Severe thirst - a late symptom of heat stress;
▪
Fainting;
▪
Heat exhaustion - fatigue, dizziness, nausea, headache, moist skin; and
▪
Heat stroke - hot dry skin, confusion, convulsions and eventual loss of consciousness. This is the most severe disorder and can result in death if not detected at an early stage.
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Element IB10: Work Environment Risks and Controls
Where Does Heat Stress Occur? Examples of workplaces where people might suffer from heat stress because of the hot environment created by the process, or restricted spaces are: ▪
Compressed air tunnels;
▪
Conventional and nuclear power plants;
▪
Foundries and smelting operations;
▪
Brick-ring and ceramics plants;
▪
Boiler rooms;
▪
Bakeries and catering kitchens; and
▪
Laundries.
In these industries working in the heat may be the norm. For others it will be encountered more irregularly depending on the type of work being done and changes in the working environment, e.g. seasonal changes in outside air temperature can be a signicant contributor to heat stress. Someone wearing protective clothing and performing heavy work in hot and humid conditions could be at risk of heat stress because: ▪
Sweat evaporation is restricted by the type of clothing and the humidity of the environment;
▪
Heat will be produced within the body due to the work rate and, if insufcient heat is lost, deep body temperature will rise;
▪
As deep body temperature rises the body reacts by increasing the amount of sweat produced, which may lead to dehydration;
▪
Heart rate also increases which puts additional strain on the body; and
▪
Should the body gain more heat than it can lose the deep body temperature will continue to rise. Eventually it reaches a point when the body’s control mechanism itself starts to fail. The symptoms will worsen the longer they remain working in the same conditions.
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Element IB10: Work Environment Risks and Controls
Cold The effect of exposure to low temperatures is to cause a nerve reaction causing vascular constriction of the skins blood vessels. This restriction has the effect of increasing the body surface insulation. This also has the effect of increasing the arterial blood pressure. Skin temperature gradually falls and the increased insulation of the shell of the body maintains deep body temperature, but with more prolonged cold stress internal heat production may then increase. This is brought about by an involuntary reex increasing muscle tone that eventually results in shivering. During bursts of intense shivering total oxygen consumption can increase by up to 5 times the basal level. Toes, ngers, ears and nose are at greatest risk bec ause these areas do not have major muscles to produce heat. In addition, the body will preserve heat by favouring the internal organs and thus reducing the ow of blood to the extremities under cold conditions. Hands and feet tend to get cold more quickly than the torso because: ▪
They lose heat more rapidly since they have a higher surface area-to-volume ratio; and
▪
They are more likely to be in contact with colder surfaces than other parts of the body.
If the eyes are not protected with goggles in high wind chill conditions, the corneas of the eyes may freeze. The most severe cold injury is hypothermia which occurs from excessive loss of body heat and the consequent lowering of the inner core temperature (internal temperature of the body). Hypothermia can be fatal and is caused when body’s core temperature starts to fall. The sensation of cold followed by pain in exposed parts of the body is one of the rst signs of mild hypothermia. As the temperature continues to drop, or as the exposure time increases, the feeling of cold and pain starts to diminish because of increasing numbness. If no pain can be felt, serious injury can occur without the victim noticing it. Next, muscular weakness and drowsiness are experienced. This condition is called hypothermia and usually occurs when body temperature falls below 33°C. Additional symptoms of hypothermia include interruption of shivering, diminished consciousness and dilated pupils. When body temperature reaches 27°C, coma (profound unconsciousness) sets in. Heart activity stops around 20°C and the brain stops functioning around 17°C.
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Element IB10: Work Environment Risks and Controls
Other Effects of Exposure to Extremes of Cold Chilblains These are a mild cold injury caused by prolonged and repeated exposure for several hours to cold air temperatures. In the affected skin area there will be redness, swelling, tingling, and pain.
Immersion Foot This occurs in individuals whose feet have been wet, but not freezing cold, for days or weeks. It can occur at temperatures up to 10°C. The primary injury is to nerve and muscle tissue. Symptoms include tingling and numbness; itching, pain, swelling of the legs, feet, or hands; or blisters may develop. The skin may be red initially and turn to blue or purple as the injury progresses. In severe cases, gangrene may develop.
Trench Foot This is ‘wet cold disease’ resulting from prolonged exposure in a damp or wet environment from above the freezing point to about 10°C. Depending on the temperature, an onset of symptoms may range from several hours to many days but the average is three days. Trench foot is more likely to occur at lower temperatures, whereas an immersion foot is more likely to occur at higher temperatures and longer exposure times. A similar condition of the hands can occur if a person wears wet gloves for a prolonged period under cold conditions described above. Symptoms are similar to an immersion foot.
Frostnip This is the mildest form of a freezing cold injury. It occurs when ear lobes, noses, cheeks, ngers, or toes are exposed to the cold and the top layers of a skin freeze. The skin of the affected area turns white and it may feel numb. The top layer of skin feels hard but the deeper tissue still feels normal (soft).
Frostbite This is a common injury caused by exposure to extreme cold or by contact with extremely cold objects (especially those made of metal). It may also occur in normal temperatures from contact with cooled or compressed gases. Frostbite occurs when tissue temperature falls below the freezing point, or when blood ow is obstructed. Blood vess els may be severely and permanently damaged, and blood circulation may stop in the affected tissue. In mild cases, the symptoms include inammation of the skin in patches accompanied by slight pain. In severe cases, there could be tissue damage without pain, or there could be burning or prickling sensations resulting in blisters. Frostbitten skin is highly susceptible to infection, and gangrene (local death of soft tissues due to loss of blood supply) may develop.
Where Does Cold Stress Occur? Articially cold workplaces include cold storage rooms, freezers, and refrigerated transportation units. Industries where workers may be exposed to natural cold include, but are not limited to, shing, forestry, construction and petroleum.
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Element IB10: Work Environment Risks and Controls
Thermal Parameters Thermo-regulation is integrated by a controlling system in the central nervous system of the body which responds to the heat content of tissues. Thermo-receptors sensitive to heat information from the skins deep tissues and central nervous system provide the feedback signals to the central controller in the hypothalamus. The temperature of the blood owing through the hypothalamus is the major regulator of body temperature. The deep body or core temperature of a narrow range around 37°C is the temperature of the deep body tissues.
Thermal Balance The body’s core temperature remains constant when there is an equilibrium between internal heat production and heat loss from the surface. Respiratory heat loss (RHS) occurs in cool environments because expired air is warmer and has a higher humidity than inspired air. For a person expending energy at 400 Wm -2 in an air temperature of minus 10°C, the RHS will be 44 W (25 Wm -2). For normal indoor activities (seated / standing) in 20°C ambient temperature, the heat loss by respiration is small (2 to 5 Wm-2) and hence is sometimes neglected. The human body may be considered to be a chemical engine, and foods with different energy content, the fuel. At rest, some of the chemical energy of food is transformed into mechanical work, e.g. in the heart beat and respiratory movements. This accounts for less than 10% of the energy produced at rest, the remainder being used in maintaining ionic gradients in the tissues and in chemical reactions in the cells, tissues and body uids. All this energy is ultimately lost from the body in the form of heat and the balance of intake and loss maintained during daily physical activity. In general, energy intake from food balances energy expenditure, except in those cases where body weight is changing rapidly. In the absence of marked weight changes, measurement of food consumption may be used in assessing habitual activity or energy expenditure, though in practice energy balance is only achieved over a period of more than one week. Energy released in the body by metabolism can be derived from measurements of oxygen consumption. The value of metabolic heat production in the basal state with complete physical and mental rest is about 45 Wm -2 for an adult male of 30 years and 41 Wm -2 for a female of the same age. Maximum values are obtained during severe muscular work and may be as high as 900 Wm-2 for brief periods. Such a high rate can seldom be maintained and performance at 400~500 Wm-2 is very heavy exercise but an overall rate that may be continued for about one hour. Metabolic heat is largely determined by muscle activity during physical work but may be increased at rest in the cold by involuntary muscle contractions during shivering.
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Element IB10: Work Environment Risks and Controls
Heat Balance In normal conditions body temperature ranges between 36 and 39°C where a thermal balance is maintained between metabolic heat, evaporation, convection, conduction radiation and heat storage (insulation). Physical law (Le Chatelier’s principle) means that when there is a ‘concentration’ of heat, it will try to ow into regions where heat energy is less concentrated. In terms of temperature, heat will therefore always ow from a high temperature to a low temperature. Body heat is transferred in four ways, this is known as the heat balance equation: M = K ± C ± R ± E: where: ▪
Conduction (K);
▪
Convection (C);
▪
Evaporation (E); and
▪
Radiation (R).
Conduction (K) Conduction is the transfer of heat through a solid. The rate at which heat is transferred by conduction depends on the temperature difference between the body and the surrounding medium, the conductance (K) and the area of contact.
Convection (C) Normally, the surface temperature of a person is higher than that of the surrounding air so that heated air close to the body will move upwards by natural convection as colder air takes its place.
Evaporation (E) Evaporative cooling is a physical phenomenon in which evaporation of a liquid, typically into surrounding air, cools an object or a liquid in contact with the air. The simplest example would be perspiration, or sweat, which the body secretes in order to cool itself. The amount of heat transfer depends on the evaporation rate, which in turn depends on the humidity of the air and its temperature, which is why humans sweat more on hot, humid days.
Radiation (R) This mode of heat transfer is completely different from conduction, convection and evaporation, which require material to transfer heat. Radiation needs no material and can pass through a vacuum. Solar heat is derived totally from radiation. Radiation energy is transferred as wave energy. It is similar to light and has similar properties: ▪
It can be transmitted through a material and will therefore not give up its energy and warm the material, e.g. air or glass (to a large extent);
▪
It may be reected from a surface. A polished or white surface has the best reective powers. Again, the temperature of the material is not raised; and
▪
It may be absorbed by material. When this occurs, the radiant energy is converted to heat energy and the temperature of the material will rise. Black surfaces are best for absorbing radiant energy. Radiant waves travel in straight lines from the heat source, therefore the intensity of the radiation decreases as the waves travel away from the source.
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Element IB10: Work Environment Risks and Controls
Measurement of the Thermal Environment The thermal environment around the body, which affects heat ow, is measured using the following parameters: ▪
The dry bulb temperature of the air;
▪
The moisture content or water vapour pressure of the air;
▪
The air velocity; and
▪
Radiant heat exchange from the skin.
Temperature Thermal comfort cannot be simply measured with a thermometer. For example, a normal or ‘dry-bulb’ thermometer in a workplace may read 21°C but if humidity is high, people are likely to feel uncomfortable unless some form of air-cooling or ventilation is provided. An acceptable zone of thermal comfort for most people lies roughly between 13°C and 30°C, with acceptable temperatures for more strenuous work activities concentrated towards the bottom end of the range, and more sedentary activities towards the higher end.
Humidity Humidity is a measure of the concentration of water vapour in the atmosphere. Where conditions of maximum vapour pressure occur, the air is said to be saturated. Humidity is expressed in terms of relative humidity. Relative humidity (RH) is a ratio and therefore has no units and is the ratio of the water vapour present to the mass of water required to saturate the same mass (at same volume and temperature). In practice, relative humidity measurement has been simplied by the use of dry air and wet bulb thermometer readings in a given atmosphere.
Relative Humidity Relative humidity (RH) is a ratio; it has no units and is dened by the following formula: Mass of water vapour in a given volume of air at a given temperature RH =
x 100 Mass of water required to saturate that volume of air at the same temperature
In practice, relative humidity measurement has been simplied by the use of dry air and wet bulb thermometer readings in a given atmosphere.
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Element IB10: Work Environment Risks and Controls
The instruments used to measure humidity are called hygrometers. There are two main types: ▪
Paper or hair hygrometers; and
▪
Whirling or wet and dry hygrometer
Both types of instrumentation work upon the comparative difference between two medium (materials or dry / wet bulbs).
Heat Flow Measurement Dry Bulb Air Temperature The dry bulb air temperature can be measured using mercury / alcohol in glass thermometers, thermocouples or resistance thermometers.
Wet Bulb Air Temperature The wet bulb temperature is obtained with the sensing head covered with a muslin sock wetted with distilled water and protected from radiant heat. Air has to ow past the wet bulb at a minimum velocity of about 4 m/s, which can be achieved by drawing air over it using a clockwork or electrically driven fan.
Black Globe (or Globe) Thermometer Measurements of radiant temperature are usually made with a black globe thermometer. It is made of a 150 mm diameter hollow copper sphere painted matt black, into which a thermometer is inserted with its bulb at the centre of the globe. The instrument has a slow response, taking about 20-30 minutes to reach equilibrium.
Kata Thermometer Air velocity is measured using an anemometer unless the value is low, in which case a kata thermometer is used. Although called a thermometer, is not strictly true as it is used to determine wind velocities. The Kata thermometers are used in conjunction with nomographs which relate the cooling times to wind velocity. The bulb is rst cleaned and then heated in hot water until the alcohol has risen to the top reservoir. The bulb is removed from the ask, dried with a clean tissue or cloth and as the thermometer cools the rate of fall of the temperature between two marks is measured. The wind speed is then determined from the Kata factor, which is engraved on the stem of the thermometer, the dry bulb air temperature and the cooling time, using the appropriate nomogram. When considering water evaporating into air, comparison between the wet bulb temperature and dry bulb temperature is a measure of the potential for evaporative cooling. The greater the difference between the two temperatures, the greater the evaporative cooling effect. When the temperatures are the same, no net evaporation of water in air occurs, thus there is no cooling effect.
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Element IB10: Work Environment Risks and Controls
Predicted Mean Vote (PMV) and Percentage People Dissatised (PPD) Index A human being’s thermal sensation is mainly related to the thermal balance of the body as a whole. This balance is inuenced by physical activity and clothing, as well as the environmental parameters: air temperature, mean radiant temperature, air velocity and air humidity. When these factors have been estimated or measured, the thermal sensation for the body as a whole can be predicted by calculating the predicted mean vote (PMV). The predicted percentage dissatised (PPD) index provides information on thermal discomfort or thermal dissatisfaction by predicting the percentage of people likely to feel too warm or too cool in a given environment. The PPD can be obtained from the PMV. The PMV is an index that predicts the mean value of the votes of a large group of persons on the 7-point thermal sensation scale.
Seven-point Thermal Sensation Scale + 3 = Hot + 2 = Warm + 1 = Slightly warm 0 = Neutral − 1 = Slightly cool − 2 = Cool − 3 = Cold
Predicted Percentage Dissatisfed (PPD) The PMV predicts the mean value of the thermal votes of a large group of people exposed to the same environment. But individual votes are scattered around this mean value and it is useful to be able to predict the number of people likely to feel uncomfortably warm or cool. The PPD is an index that establishes a quantitative prediction of the percentage of thermally dissatised people who feel too cool or too warm. The PMV and PPD express warm and cold discomfort for the body as a whole. But thermal dissatisfaction can also be caused by unwanted cooling or heating of one particular part of the body. This is known as local discomfort . The most common cause of local discomfort is draught. But local discomfort can also be caused by an abnormally high vertical temperature difference between the head and ankles, by too warm or too cool a oor. It is mainly people at light sedentary activity who are sensitive to local discomfort. These will have a thermal sensation for the whole body close to neutral. At higher levels of activity, people are less thermally sensitive and consequently the risk of local discomfort is lower. Due to individual differences, it is impossible to specify a thermal environment that will satisfy everybody. There will always be a percentage dissatised occupants. But it is possible to specify environments predicted to be acceptable by a certain percentage of the occupants. There are two published standards that can be used to work out thermal comfort: ▪
ISO 10551:2001 Assessment of the inuence of the thermal environment using subjective judgement scales.
▪
BS EN ISO 7730:2005 Analytical determination and interpretation of thermal comfort using calculation of the PMV and PPD indices and local thermal comfort criteria.
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Element IB10: Work Environment Risks and Controls
Heat Gain and Loss Other factors that affect bodily heat gain and loss are: ▪
The metabolic rate;
▪
The type of clothing worn; and
▪
The duration of exposure.
An individual’s metabolic rate of an individual is governed largely by his / her activity or work rate. Work rates tend to be self-regulating as workers will voluntarily reduce their work rate when they feel overheated. For the human body there are three different components which inuence the rate of heat transfer, the insulation factors of the skin tissues, clothing and the air. An arbitrary unit of insulation, the Clo, is used for assessing the insulation value of ‘clothing assemblies’. Clothing assemblies have varying resistances to heat ow. Examples of typical clothing insulation values are given in Table 1. Table 1: Examples of typical clothing and insulation values Type of Clothing
Id(Clo)
Nude.
0
Shorts only.
0.1
Summer clothing.
0.5
Suit.
1.5
Winter clothing (coat, gloves, etc).
2.0
Specialist thermal clothing.
3 to 5
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Element IB10: Work Environment Risks and Controls
Heat Indices To assess a thermal environment the following indices are used when evaluating the effects of heat and cold.
Effective Temperature (ET) This takes into account wet bulb temperature, dry bulb temperature and air veloci ty. Using these measurements the ET is derived from ‘basic’, ‘normal’ and ‘adjusted’ scales on nomograms. The scales were derived from subjective studies with environments providing the same sensation allocated equal values. The basic scale relates to a worker stripped to the waist, the normal scale relates to a lightly clothed worker and the adjusted scale takes account of the work rate.
The Corrected Effective Temperature (CET) This uses the same principles as effective temperature but corrects the index to take account of radiant heat, so the globe temperature reading is used instead of the dry bulb temperature.
The Heat Stress Index (HSI) This aims to predict thermal effects on the body by balancing heat inputs (from the environment and from the metabolic rate) against heat loss by the evaporation of sweat. The index takes into account all the environmental parameters, work rate, and clothing, as well as the evaporative efciency of sweat rate. HSI is the ratio of the required heat loss, Ereq (depending on metabolic rate, radiation loss and convection loss) to the maximum loss available by evaporation, Emax (depending on air velocity and humidity). The index is expressed as a number between 0 and 100. Conditions giving an HSI below 40 are not considered to pose a risk to health; above 40 the risk increases; and 100 represents the situation where the heat gain just matches that lost by evaporation. Over 100 there is a net heat gain to the body which means that the body core temperature will rise unless the exposure time is limited.
The Predicted 4-hour Sweat Rate (P4SR) This uses six different thermal parameters to calculate a nominal sweat rate that would be necessary to maintain thermal equilibrium. This sweat rate can be used as an index of strain on the individual and limiting values can be set for different circumstances.
The Wind Chill Index This is a measure of heat loss from the body to quantify the risk resulting from the combined cooling effect of wind and cold conditions. It is an empirical index based on measurements made on an articial human under different conditions of wind speed and temperature. The index is often used by weather forecasters to indicate the equivalent perceived temperature on cold and windy days. The index is useful in identifying conditions of potential danger when skin surfaces are exposed. For example, a wind chill index of 1,392 W/m2 is equivalent to a chilling temperature of -21°C and has the effect of freezing exposed esh after 60 minutes. However, under more extreme conditions a wind chill index of 2,784 W/m2 is equivalent to a chilling temperature of -76°C and has the effect of freezing exposed esh after only one minute.
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Element IB10: Work Environment Risks and Controls
Using These Heat Indices There are a number of indices of increasing complexity. In principle these are calculated from a combination of environmental / physiological parameters to give a single number. This number is then compared with a table of limiting values which will indicate the maximum time that the person should work under this heat stress. Corrected Effective Temperature Index (CET) can be obtained from a chart and takes into account work rate and clothing. Wet Bulb Globe Temperature Index (WBGT) calculated as follows: INDOORS: WBGT = 0.7 x Wet Bulb Temp + 0.3 x Globe Temp. OUTDOORS: WBGT = 0.7 x Wet Bulb Temp + 0.2 x Globe Temp + 0.1 x Dry Bulb. The duration of exposure can be varied by work / rest regimes. Table 2: WGBT’s (°C) and Recommended Work/Rest Regimes Workload (Total) Light
Moderate
Heavy
Continuous
30.0
26.7
25.0
75% work, 25% rest each hour
30.6
28.0
25.0
50% work, 50% rest each hour
31.4
29.4
27.9
25% work, 75% rest each hour
32.2
31.1
30.0
Table 2 illustrates how the WBGT can be used to set work / rest regimes. For example, at a WBGT of 30°C, an individual could undertake light work continuously, but if heavy work was involved he / she could only maintain it for 25% of the time in any hour. H.S.I. - can be calculated or obtained from charts and takes into account clothing and work rate, and from it can be obtained recommended duration’s of work and rest periods. P4SR - can be obtained from charts and takes into account work rate and clothing.
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Element IB10: Work Environment Risks and Controls
Control There a range of factors to consider when developing appropriate controls for extremes of temperature. The following control strategies are recommended: ▪
If possible remove or reduce the sources of heat; and
▪
Control the temperature using engineering solutions, e.g. building design the most effective way of ensuring thermal comfort is to design the workplace appropriately.
A number of issues can be addressed as follows: ▪
Heating. Many types of heating are available such as hot air heated by gas or oil burners, central heating by steam heat circulated through radiators, combined heating and ventilating systems where the air-conditioning system is used to heat air which is then circulated, electric heaters, oor heating or overhead radiant heating from gas or electric;
▪
Air Movement. Small personal fans can provide a refreshing movement of air on the face and larger oscillating fans can provide a swirling air movement, although some people nd this ‘draughty’. Large diameter fans suspended from the ceiling can provide a swirling air movement that is effective over wide areas. Exhaust fans mounted in the roofs and walls are useful for removing heated air, however, whilst improving general air movement they may have little effect on thermal comfort;
▪
Air-Conditioning. This can range from small units that lower the air temperature but do not control humidity levels or air movement, to large units that can cope with extreme conditions, and also control humidity and air movement;
▪
Evaporative Cooling. These produce a moderate reduction in air temperature and increase humidity. They operate by passing hot air over water-saturated pads and the water evaporation effect reduces the dry-bulb temperature;
▪
Thermal Insulation. There are many different types of thermal insulation materials such as loose lls, foams, rock wool and boards. The material acts as a barrier that retards heat ow in the summer and heat loss in the winter. It is only effective where there is a temperature difference between the inside and the outside of the building or between two areas inside a building;
Regulate the length of exposure to hot environments by: ▪
Allowing workers to enter only when the temperature is below a set level or at cooler times of the day;
▪
Issuing permits-to-work that specify how long your workers should work in situations where there is a risk; and
▪
Providing periodic rest breaks and rest facilities in cooler conditions.
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Prevent dehydration. Working in a hot environment causes sweating which helps keep people cool but means losing vital water that must be replaced. Provide cool water in the workplace and encourage workers to drink it frequently in small amounts before, during and after working; Provide personal protective equipment. Specialised personal protective clothing is available which incorporates, for example, personal cooling systems or breathable fabrics. This may help protect workers in certain hot environments. Protective clothing or respiratory protective equipment is often required when there will be exposure to some other hazard at work, e.g. asbestos. This type of equipment, while protecting from the other hazard, may increase the risk of heat stress; Provide training, especially new and young employees, telling them about the risks of heat stress associated with their work, what symptoms to look out for, safe working practices and emergency procedures; allow workers to acclimatise to their environment and identify which workers are acclimatised / assessed as t to work in hot conditions; Identify employees who are more susceptible to heat stress either because of an illness / condition or medication that may encourage the early onset of heat stress, e.g. pregnant women or those with heart conditions; and Monitor the health of workers at risk. Where it is considered that a residual risk remains after implementing as many control measures as practicable, the health of workers exposed to the risk may need to be monitored.
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Element IB10: Work Environment Risks and Controls
Lighting Lighting should be sufcient to enable people to work, use facilities and move from place to place safely and without experiencing eye-strain. Stairs should be well lit in such a way that shadows are not cast over the main part of the treads. Where necessary, local lighting should be provided at individual workstations, and at places of particular risk, such as pedestrian crossing points on vehicular trafc routes. Ideally, good lighting should ‘guarantee’: ▪
Employee safety;
▪
Acceptable job performance; and
▪
Good workplace atmosphere, comfort and appearance.
This is not just a matter of maintaining of correct lighting levels. To accommodate these ‘requirements’, a combination of general and localised lighting (not to be confused with ‘local’ lighting, e.g. desk light) is necessary.
Types of Lighting Natural Lighting Daylight is the natural, and cheapest, form of lighting, but it has only limited application to places of work where production is required beyond the hours of daylight. However good the outside daylight, windows can rarely provide adequate lighting alone for the interior of large oor areas. Single storey buildings can, of course, make use of insulated opaque roong materials, but the most common provision of daylight is by side windows. There is also the fact that the larger the glazing area of the building, the more other factors such as noise, heat loss in winter, and unsatisfactory thermal conditions in summer must be considered. Modern conditions, where the creation of pleasant building interior environment requires the balanced integration of lighting, heating, air conditioning, acoustic treatment, etc. are such that lighting cannot be considered in isolation. At the very least, natural lighting will have to be supplemented for most of the time with articial lighting, the most common source being electric lighting.
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Element IB10: Work Environment Risks and Controls
Articial Lighting Capital costs, running costs and replacement costs of various types of electric lighting have a direct bearing on the selection of the sources of electric lighting for particular application. Such costs are as important considerations as the size, heat and colour effects required of the lighting. The efciency of any type of lamp used for lighting is measured as light output, in lumens per watt of electricity. In general, the common incandescent lamps (coiled lament lamps, the temperature of which is raised to white heat by the passage of current, thus giving out light) are relatively cheap to install but have relatively expensive running costs. A discharge or uorescent lighting scheme (which works on the principle of electric current passing through certain gases and thereby producing an emission of light) has higher capital costs but higher running efciency, lower running costs and longer lamp life. In larger places of work the choice is often between discharge and uorescent lamps.
Lighting Design While the quantity of lighting afforded to a particular location or task in terms of standard service illuminance is an important feature of lighting design, it is also necessary to consider the qualitative aspects of lighting, which have both direct and indirect effects on the way people perceive their work activities and dangers that may be present. The presence or absence of glare, the distribution of the light, brightness, diffusion and colour rendition affects the quality of lighting.
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Hazards Associated with Lighting Glare This is the effect of light that causes impaired vision or discomfort experienced when parts of the visual eld are excessively bright compared with the general surroundings. Glare can be experienced in three different forms: ▪
Disability glare – the visually disabling effect caused by bright bare lamps directly in the line of vision, e.g. at night, a car with its lights on full beam;
▪
Discomfort glare – caused by too much contrast of brightness between an object and its background, and frequently associated with poor lighting design. It can cause discomfort without necessarily impairing the ability to see detail. Over a period it can cause visual fatigue, headaches and general fatigue; and
▪
Refected glare – is the reection of bright light sources on shiny or wet work surfaces, such as plated metal or glass, which can almost entirely conceal the detail in or behind the object that is glinting.
Colour Rendition Colour rendition refers to the appearance of an object under a specic light source, compared to its colour under a reference illuminant, e.g. natural light. Good standards of colour rendition allow the colour appearance of an object to be properly perceived. Generally, the colour rendering properties of luminaires should not clash with those of natural light, and should be just as effective at night when there is no daylight contribution to the total illumination of the working area.
Stroboscopic Effect One aspect of lighting quality that formerly gave troubl e was the stroboscopic effect of uorescent tubes that gave the illusion of motion or even the illusion that a rotating part of machinery was stationary. With modern designs of uorescent tubes, this effect has largely been eliminated.
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Flicker Light modulation at lower frequencies (about 50 Hz or less) which is visible to most people, is called icker. Flicker is a source of both discomfort and distraction, and may even cause epileptic seizures in some people. Sensitivity to icker varies widely between individuals. The perceptibility of icker is inuenced by the frequency and amplitude of the modulation and the area of vision over which it occurs. The eye is most sensitive to icker at the edge of the eld of view; thus visibly ickering overhead lights can be a source of great discomfort.
Veiling Reections Veiling reections are high-luminance reections that overlay the detail of the task. Such reections may be sharp-edged or vague in outline, but regardless of form they may affect task performance and cause discomfort. Task performance will be affected because veiling reections usually reduce the contrast of a task, making task details difcult to see, and may give rise to discomfort, e.g. reections on a computer screen.
Radiation All light sources radiate energy at shorter wavelengths in the ultra-violet as well as at longer wavelengths in the infrared parts of the spectrum. This radiation can promote physiological effects that are either a benet or a hazard.
Lasers See Element B7 for details of the hazards associated with the use of lasers.
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Element IB10: Work Environment Risks and Controls
Measurement of Illuminance The standard of illuminance (i.e. the amount of light) required for a given location or activity depends on a number of variables, including general comfort considerations and the visual efciency required. The unit of illuminance is the ‘lux’, which equals one lumen per square metre: this unit has now replaced the ‘foot candle’ which was the number of lumens per square foot. The term ‘lumen’ is the unit of luminous ux, describing the quantity of light received by a surface or emitted by a source of light.
Light Measuring Instruments Measurement at a particular working point requires a reliable instrument. Such an instrument, suitable for most measurements, is a pocket lightmeter that incorporates the principle of the photo-electric cell, which generates a tiny electric current in proportion to the light at the point of measurement. This current deects a pointer on a graduated scale measured in lux. Manufacturers’ instructions should, of course, be followed in the care and use of such instruments.
Average Illuminance and Minimum Measured Illuminance Illuminance levels need to be related to the degree or extent of detail that needs to be seen in a particular task or situation. Various guidance exists, identifying recommendations both for average illuminance for the work area as a whole and for minimum measured illuminance at any position within it. As the illuminance produced by any lighting installation is rarely uniform, the use of the average illuminance gure alone could result in the presence of a few positions with much lower illuminance that pose a threat to health and safety. The minimum measured illuminance is therefore the lowest illuminance permitted in the work area taking health and safety requirements into account. The planes on which the illuminances should be provided depend on the layout of the task. If predominantly on one plane, e.g. horizontal, as with an ofce desk, or vertical, as in a warehouse, the recommended illuminances should be provided for that plane. Where there is either no well dened plane or more than one, the recommended illuminances should be provided on the horizontal plane and care taken to ensure that the reectance of surfaces in working areas are high. Table 3: Illuminance standards (HSG38 Lighting as Work) Nature of Work Example
Illumination (Lux)
Rough Tasks Large detail: heavy machinery, stores, corridors.
300
Ordinary Tasks Medium detail: general assembly work, ofces.
500
Severe Tasks Small details: clothing manufacture, drawing ofce, typing.
750
Prolonged Tasks Small detail. Minute detail.
1,000 1,500 – 3,000
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Illuminance Ratios The relationship between the lighting of the work area and adjacent areas is signicant. Large differences in illuminance between these areas may cause visual discomfort or even affect safety levels where there is frequent movement, e.g. fork-lift trucks. This problem arises most often where local or localised lighting in an interior exposes a person to a range of illuminance for a long period, or where there is movement between interior and exterior working areas exposing a person to a sudden change of illuminance.
Maintenance of Light Fitments The lighting output of a given lamp will reduce gradually in the course of its life but regular cleaning and maintenance, not only of the lamp itself but also of the reectors, diffusers and other parts of the luminaire, can obtain an improvement. A sensible and economic lamp replacement policy is called for (e.g. it may be more economical, in labour cost terms to change a batch of lamps than deal with them singly as they wear out).
Distribution Distribution is concerned with the way light is spread. The actual spacing of luminaires is also important when considering good lighting distribution. To ensure evenness of illuminance at operating positions, the ratio between the height of the luminaire and the spacing of it must be considered. The IES spacing: height ratio provides a basic guide to such arrangements. Under normal circumstances, e.g. ofces, workshops and stores, this ratio should be between 11/2:1 and 1:1 according to the type of luminaire.
Brightness Brightness or ‘luminosity’ is very much a subjective sensation and, therefore, cannot be measured. However, it is possible to consider a brightness ratio, which is the ratio of apparent luminosity between a task object and its surroundings. To ensure the correct brightness ratio, the reectance (i.e. the ability of a surface to reect light) of all surfaces in the working area should be well maintained and consideration given to reectance values in the design of interiors. Given a task illuminance factor (i.e. the recommended illuminance level for a particular task) of 1, the effective reectance values should be ceilings – 0.6, walls – 0.3 to 0.8, and oors – 0.2 to 0.3.
Diffusion This is the projection of light in all directions with no predominant direction. The directional ow of light can often determine the density of shadows, which may prejudice safety standards or reduce lighting efciency. Diffused lighting will reduce the amount of glare experienced from bare luminaires.
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Welfare Facilities ‘Welfare facilities’ is a wide term, embracing both sanitary and washing accommodation at workplaces, provision of drinking water, clothing accommodation (including facilities for changing clothes) and facilities for rest and eating meals. The International Labour Standard R102 Welfare Facilities Recommendation, 1956, establis hes requirements in relation to feeding, rest and recreational facilities. The need for sufcient suitable hygienic lavatory and washing facilities in all workplaces is obvious. Sufcient facilities must be provided to enable everyone at work to use them without undue delay. They do not have to be in the actual workplace but ideally should be situated in the building(s) containing them and they should provide protection from the weather, be wellventilated, well-lit and enjoy a reasonable temperature. Where disabled workers are employed, special provision should be made for their sanitary and washing requirements. Wash basins should allow washing of hands, face and forearms and, where work is particularly strenuous, dirty, or results in skin contamination (e.g. molten metal work), showers or baths should be provided. In the case of showers, they should be fed by hot and cold water and tted with a thermostatic mixer valve. Washing facilities should ensure privacy for the user and be separate from the water closet, with a door that can be secured from the inside; nor should it be possible to see urinals or the communal shower from outside the facilities when the entrance/exit door opens. Entrance / exit doors should be tted to both washing and sanitary facilities (unless there are other means of ensuring privacy). Windows to sanitary accommodat ion, showers and bathrooms should be obscured, either by being frosted or by blinds or curtains (unless it is impossible to see into them from outside).
Sanitary Conveniences Suitable and sufcient sanitary conveniences should be provided at readily accessible places. In particular: ▪
The rooms containing them must be adequately ventilated and lit;
▪
They (and the rooms in which they are situated) must be kept clean and in an orderly condition; and
▪
Separate rooms containing conveniences must be provided for men and women except where the convenience is in a separate room which can be locked from the inside.
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Washing Facilities Suitable and sufcient washing facilities (including showers where necessary), should be provided at readily accessible places or points. In particular, facilities should: ▪
Be provided in the immediate vicinity of every sanitary convenience (whether or not provided elsewhere);
▪
Be provided in the vicinity of any changing rooms – whether or not provided elsewhere;
▪
▪
include a supply of clean hot and cold or warm water (if possible, running water);
▪
include soap (or something similar);
▪
include towels (or the equivalent);
▪
be in rooms sufciently well-ventilated and well-lit;
Be kept clean and in an orderly condition (including rooms in which they are situated); and be separate for men and women, except where they are provided in a lockable room intended to be used by one person at a time, or where they are provided for the purposes of washing hands, forearms and face only, where separate provision is not necessary.
At temporary work sites suitable and sufcient sanitary conveniences and washing facilities should be provided so far as is reasonably practicable. If possible, these should incorporate ushing sanitary conveniences and washing facilities with running water.
Drinking Water An adequate supply of wholesome drinking water should be provided for all persons at work in the workplace. It should be readily accessible at suitable places and conspicuously marked, unless non-drinkable cold water supplies are clearly marked. In addition, there must be provided a sufcient number of suitable cups (or other drinking vessels), unless the water supply is in a jet. Where water cannot be obtained from the mains supply, it should only be provided in rellable containers. The containers should be enclosed to prevent contamination and relled at least daily.
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Element IB10: Work Environment Risks and Controls
Clothing Accommodation Suitable and sufcient accommodation must be provided for: ▪
Any person at work’s own clothing which is not worn during working hours; and
▪
Special clothing which is worn by any person at work but which is not taken home, for example overalls, uniforms and thermal clothing.
Accommodation is not suitable unless it: ▪
Provides suitable security for the person’s own clothing where changing facilities are required;
▪
Includes separate accommodation for clothing worn at work and for other clothing, where necessary to avoid risks to health or damage to clothing;
▪
So far as is reasonably practicable, allows or includes facilities for drying clothing; and
▪
Is in a suitable location.
Work clothing is overalls, uniforms, thermal clothing and hats worn for hygiene purposes. Workers’ own clothing should be able to hang in a clean, warm, dry, well-ventilated place. If this is not possible in the workroom, then it should be put elsewhere. Accommodation should take the form of a separate hook or peg. Clothing which is dirty, damp or contaminated owing to work should be accommodated separately from the worker’s own clothes.
Facilities for Changing Clothing Suitable and sufcient facilities must be provided for any person at work in the workplace to change clothing where: ▪
The person has to wear special clothing for work; and
▪
The person cannot be expected to change in another room; and
▪
The facilities are easily accessible, of sufcient capacity and provided with seating.
Facilities are not suitable unless they include: ▪
Separate facilities for men and women, or
▪
Separate use of facilities by men and women.
Changing rooms (or room) should be provided for workers who change into special work clothing and where they remove more than outer clothing; also where it is necessary to prevent workers’ own clothes being contaminated by a harmful substance. Changing facilities should be easily accessible from workrooms and eating places. They should contain adequate seating and clothing accommodation, and showers or baths if these are provided. Privacy of user should be ensured. The facilities should be large enough to cater for the maximum number of persons at work expected to use them at any one time without overcrowding or undue delay.
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Rest and Eating Facilities Suitable and sufcient rest facilities should be provided at readily accessible places. ▪
Appropriate facilities for eating meals where food eaten in the workplace would otherwise be likely to become contaminated;
▪
Suitable arrangements for protecting non-smokers from discomfort caused by tobacco smoke;
▪
An adequate number of tables and adequate seating with backs for the number of persons at work likely to use them at any one time;
▪
Seating which is adequate for the number of disabled persons at work and suitable for them; and
▪
Facility for a pregnant or nursing mother to rest in.
Rest facilities should be large enough, and have enough seats with backrests and tables, for the number of workers likely to use them at one time and seating which is adequate for the number of disabled persons at work and suitable for them. Where workers regularly eat meals at work, there should be suitable and sufcient facilities. These should be provided where food would otherwise be contaminated, by dust or water, for example. Seats in work areas can be suitable for eating facilities, provided the work area is clean. There should be a means to prepare or obtain a hot drink, and where persons work at places where hot food cannot be readily obtained, there should be the means for heating their own food. Eating facilities should be kept clean.
Disabled Persons Where necessary, parts of the workplace (including in particular doors, passageways, stairs, showers, washbasins, lavatories and workstations) used or occupied directly by disabled persons at work should be organised to take account of such persons.
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First Aid Introduction The ILO dene First aid as: ‘the assessment and intervention that can be performed by a rst aider during an emergency with minimal equipment until appropriate medical personnel arrive’ The aim of First-aid is: ▪
Preserve life
▪
Prevent illness or injury from becoming worse
▪
Reduce pain
▪
Promote recovery; and
▪
Care of unconscious.
The ILO Code of Practice: Safety in the use of chemicals at work implementing the Chemicals Convention 1990 (No. 170) identify that ‘ Arrangements should be made to deal at all times, and in accordance with any requirements laid down by the competent authority or as advised by the assessment of risks, with emergencies and accidents which might arise from the use of hazardous chemicals at work’.
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Assessment of First-Aid Requirements An employer should make an assessment of rst-aid needs. Consideration of the following is required: ▪
Workplace hazards and risks, e.g. if an electro-plating operation where cyanide salts are used there will be a potential risk of cyanide poisoning, which requires very specic treatment;
▪
The size of the organisation;
▪
The organisation’s history of accidents;
▪
The nature and distribution of the workforce;
▪
The remoteness of the site from emergency medical services;
▪
The needs of travelling, remote and lone workers;
▪
Employees working on shared or multi-occupied sites; and
▪
Annual leave and other absences of rst-aiders and appointed persons.
Having made this assessment, the employer will then be able to work out the number and size of rst-aid boxes required. At least one will always be required. Additional facilities such as a stretcher or rst-aid room may also be appropriate. The employer must ensure that adequate numbers of ‘suitable persons’ are provided to administer rst-aid. Suitable persons are those who have received training and acquired a qualication, and any additional training which might be appropriate under the circumstances, such as in relation to any special hazard. All relevant factors have to be taken into account when deciding how many ‘suitable persons’ will be needed. These include: ▪
Situations where access to treatment is difcult. First-aiders would be required where work activities are a long distance from accident and emergency facilities;
▪
Sharing rst-aiders. Arrangements can be made to share the expertise of personnel. Usually, as on a multi-contractor site, one contractor supplies the personnel;
▪
Employees regularly working away from the employer’s premises;
▪
The numbers of the employees, including uctuations caused by shift patterns. The more employees there are, the higher the probability of injury; and
▪
Absence of rst-aiders through illness and annual leave.
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Number of Appointed Persons and First-Aiders The ILO Code species that ‘As far as is practicable, appropriate means and trained personnel for rendering rst aid should be readily available at all times during the use of hazardous chemicals at work’ For example within the UK as a minimum, the employer should provide rst aid provision as detailed in the table 4: Table 4: Suggested Numbers of First Aid Personnel in the UK Category of risk
Numbers employed at any location personnel
Suggested number of rst-aiders
Lower risk, e.g. shops, ofces, libraries.
Fewer than 50
At least one appointed person.
50 – 100
At least one rst-aider.
More than 100
One additional rst aider for every 100 employed.
Fewer than 20
At least one appointed person.
20 -100
At least one rst-aider for every 50 employed (or part thereof).
More than 100
One additional rst-aider for every 100 employed.
Fewer than 5
At least one appointed person.
5 – 50
At least one rst-aider.
More than 50
One additional rst-aider for every 50 employed
Where there are hazards for which additional rst-aid skills are necessary
In addition, at least one rst-aider trained in the specic emergency action.
Medium risk, e.g. light engineering and assembly work, food processing, warehousing.
Higher risk, eg. most construction, slaughterhouse, chemical manufacture, extensive work with dangerous machinery or sharp instruments.
In circumstances where the rst-aider is absent in temporary and exceptional circumstances such as sudden illness (but not through planned annual leave), an employer can appoint a person to take charge in an emergency including the equipment and facilities provided. Also, in appropriate circumstances, an employer can provide an ‘appointed person’ instead of a rstaider. He must rst consider the nature of the work, the number of employees and the location of the workplace. The ‘appointed person’ only will be adequate. However, as a minimum an employer must provide an ‘appointed person’ at all times when employees are at work. Self-employed people must ensure that adequate and suitable provision is made for administering rst-aid while at work. Again, an assessment has to be made of the likely hazards and risks to determine the extent and nature of what needs to be provided. It is also possible for the self-employed to make arrangements to share facilities.
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First-Aid Rooms Employers should provide a suitable rst-aid room (or rooms) where the assessment of rstaid needs identies this as necessary. The rst-aid room(s) should contain essential rst-aid facilities and equipment, be easily accessible to stretchers, and be clearly signposted and identied. If possible the room(s) should be reserved exclusively for giving rst-aid. A rst-aid room (or rooms) will usually be necessary in establishments with high risks, e.g. chemical industries, large construction sites and in larger premises at a distance from medical services. A designated person should be given responsibility for the room.
Information for Employees Employers should inform employees about the rst-aid arrangements, including the location of equipment, facilities and identication of trained personnel. This is normally provided at induction training, or when commencing work in a new area. This is normally done by describing the arrangements in the safety policy statement, displaying at least one notice giving details of the location of facilities and trained personnel.
First-Aid Boxes The ILO Code of Practice requires that ‘adequate rst-aid arrangements should be provided. These arrangements should take account of the hazardous chemicals used at work, ease of communications, and the emergency services and facilities available. They should be in accordance with any requirements laid down by the competent authority’. For example the USA OSHA standard 1910.151 (b) rst aid training in general industry, also states an employer must have “adequate rst aid supplies...readily available,” although specic rst aid supplies are not listed. OSHA does not have a minimum requirement, but references ANSI Z308.1-2003 Minimum Requirements for Workplace First Aid Kits. First-aid boxes, which are to form part of an establishment’s permanent rst-aid provision, should contain only those items that a rst-aider has been trained to use. Sufcient quantities of each item should always be available in every rst-aid box or container. In most cases these will be: ▪
One guidance card;
▪
Twenty individually wrapped sterile adhesive dressings (assorted sizes) appropriate to the work environment (which may be detectable for the catering industry);
▪
Two sterile eye pads, with attachment;
▪
Six individually wrapped triangular bandages;
▪
Six safety pins;
▪
Six medium sized individually wrapped sterile un-medicated wound dressings (approx. 10 cm x 8 cm);
▪
Two large sterile individually wrapped un-mediated wound dressings; and
▪
Three extra sterile individually wrapped un-medicated wound dressings (approx. 28 cm x 17.5 cm).
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