Occupational Safety and Standards in Milling

13 August 201425 min reading
Aiming the protection of employees, the business and the production in a business from any hazard and damage; occupational safety still does not have sufficient importance in the developing or underdeveloped countries while it is a significantly important concept for the businesses in the developed countries. Therefore a large number loss of lives, loss of limbs and injuries continue to occur due to the occupational accidents. The only way that the businesses can get rid of the occupational accidents causing these kinds of losses is to apply a proper occupational safety system. The concept of occupational safety includes the protection of business employees, the business itself and production from any hazard and damage. However, business and the production safety are of secondary importance as human life is first and foremost. Thus, it is more proper to discuss occupational safety with an approach of "employees 'safety' priority basically. Whereas any financial loss can be compensated, there is no possibility of compensating human life. Businesses should aim to prevent standard hazards, foresee possible risks and eliminating or minimizing these risks while making studies on occupational safety. OCCUPATIONAL SAFETY RISKS IN FLOUR MILLS Flour mills are included within the manufacturing industry on the workplace hazard classes list published by General Directorate of Development of Legislation and Publication in Turkey and considered in the “Dangerous” class. On a sample risk assessment report made for a flour plant; possible risk sources that may be encountered in plants’ various parts such as office building, the boiler room, transport and storage of raw materials, production, laboratory, packaging and transport or throughout the plant are discussed. - Electrical Installations and Fire Extinguishing Systems Major elements that may pose a risk throughout the plant are electrical panels and installations. Possible electrical leakage in those parts can cause serious results such as injury or death. Precautions that should be taken for this issue are making electrical grounding measurements annually, making maintenance of electrical panels regularly, hanging warning signs on the electrical boards, putting insulating mats in front of the electrical boards and realization of the maintenance by authorized personnel. Another risk factor is fire-extinguishing system. Lack of fire-extinguishing systems, not easily accessible placement of these systems or being neglected of these systems would hinder a possible intervention in case of fire. As a result of that; injury, death or material damages are likely to occur. In order not to encounter these risks; effective and adequate fire-fighting equipment and fire detectors and alarm systems when necessary should be kept indoor and outdoor spaces in the workplace depending on the size of the workplace, on the nature of the work performed, and the physical and chemical properties of the materials used on the number of employees. Firefighting equipment should be used easily, placed at visible and easily accessible places and there should not be obstacles in front of them. Motor pumps and motor pumps with piping that will draw the water should be kept in in the workplaces in a condition of working properly all the time. Motor pumps should be checked at least every 6 months and the checking dates should be written on the motor pump. Fire hydrants in the workplaces should be kept easily accessible places and the installation should be protected as required in order to prevent water freezing in cold weather. Fire hydrants should be opened and drained often and thus the accumulation of residues inside the pies and plants should be prevented. Fire hoses in sufficient numbers should be kept in the suitable places of the workplaces; fire hoses, fire hydrants and other fire protection equipment connections (record and valves) should be pursuant to the local fire norms. - Lightning Systems Lack of lightning system (lightning rod) in the plants and insufficient periodical controls of these systems are another risk factor. A possible streak of lightning and fire and explosions as a result of that can cause injury, death and material damages. In order not to experience these situations; the work equipment whose usage may cause streak of lightning should be protected by appropriate means against the effects of lightning. Lightning rods and other protective installations against lightning should be checked by qualified personnel at least once a year. - Alert and Warning Signs and Boards Lack of alert and warning sign and board increases the occupational accidents. Therefore; shape and color of the signs that would be used for prohibitions, warnings, orders, escape way in case of emergency or that indicating equipment for firefighting should be designed according to their specific objectives. The signs should be made of impact and weather resistant material that is appropriate for the environment. The size and colorimetric and photometric features of the signs would ensure that they are easily visible and understandable. - Showers, Sinks, Toilets and Locker Rooms Showers, sinks, toilets, locker rooms and cloth closets are important in terms of infectious diseases. These places are effective in the increase of occupational diseases, infection of various bacteria and harmful microorganisms. Thus, aspiration and ventilation apparatus suitable for adequate ventilation in the shower cabins should be kept and the odor and dirt should be prevented. The shower cabins should be heated sufficiently according to the seasons and the temperature should not below 250C. It is essential that hot and cold running water in the showers should be set to be in a good condition and flow with sufficient pressure. Soap and other material necessary for taking a shower should be provided by the employer. Clean towels and peshtemals for using in the showers should be kept in special cabinets; the used ones should be washed and dried and should be used by somebody else before being cleaned well. Special baskets for dirty towels and similar material and special waste bins whose top are clamped should be kept in the shower lockers. Besides regular cleaning and maintenance, showers should be washed and cleaned well and disinfected every 15 days. Sewage systems should be pursuant to the regulation and cesspits should only be allowed in which there are not any sewer system and connections. The cesspits should not be built 30 meters closer to the places where foodstuffs are stored or processed. The closets of the workers should be locked and the cleaning of them should be made according to a directive prepared by the employer. In poisonous, hazardous, dusty and dirty workplaces; workers should have 2 separate closets that are not adjoined for putting work clothes and other clothes separately. The maintenance of lockers, wardrobes and closets should be made and the workers should not work in wet clothes. - Working in Shifts Working in shifts creates sleeplessness and tiredness and these bring carelessness during working and may cause occupational accidents. Therefore, workers should work at most 7,5 hours on the night shifts. In the workplaces that are operated day and night and in which worker teams work in shifts, the workers that work at night at most one week should work in the day shift in the following second work week. Fortnightly alternation basis with day and night shifts can be applied for the qualification and execution of the work by considering the occupational health and safety. At the shift changes, the workers should rest for at least 11 hours continuously before starting to work. The workers should also have breaks. These breaks are included in the legal regulations of many countries. - Emergency Exit Routes and Doors Improper emergency exit routes and doors may cause that the employees cannot leave the danger zone in a possible case of danger. Emergency exit routes and doors should be opened to outside or to a safe place and there should not be any hinder that prevents the exit. In any case of danger, it should be made possible for all of the employees to leave the workplace promptly and safely. The number, size and places of the emergency routes and doors should be suitable for the qualification of the work performed, size of the workplace and the number of the employees. Rail or revolving doors should be used as emergency door, the doors should be opened to outside, they should not be locked or tied up and should be opened promptly and easily by the employees in case of emergency. Spare lighting system that would provide the sufficient lighting in case of power failure at the emergency route and doors that are needed be lightened should be kept. - Fuel Tank Fuel tanks bring fire and explosion risks together. Therefore, the storages made for fuel on the ground should be sited on a solid base and surrounded by proper safety walls. Ceiling of these storages should be made of iron sheet thinner than the ones on the sides. Remote controlled fire extinguishing equipment, pressure valve that automatically opens and closes in certain pressure change, a ladder that provides comfortable climbing to the measurement opening, a railing surrounding the floor and similar protective equipment should be kept in the storages on the ground. - Occupational Health and Safety Training The lack of Occupational Health and Safety training for the employees is an effective factor in the increase of occupational accidents. Occupational health and safety training should be provided to the employees. This training should be provided especially before starting to work, in case of workplace or work change, working equipment change or application of new technology. The training should be renewed according to the change and formation of new risks and should be repeated regularly when necessary. Especially the employee representatives should be trained. - Inadequate Ventilation and Inappropriate Ambient Temperature Inadequate ventilation and inappropriate ambient temperature cause work stress, inattention and suffocation for the workers and thus bring occupational accidents. Sufficient fresh air needed by the employees depending on the way of work and the work they do should be provided in the indoor workplaces. When the forced ventilation system is used, the system should also be in a condition of working properly all the time; if the failure of the ventilation system is hazardous for the health of the employees, there should be a warning system that reports the failure. Air flow in the artificial ventilation systems should not disturb the employees. Residues and contaminants that may harm the employees’ health by polluting the air of the work environment should be thrown outside. The temperature of the work environment should be suitable for the way of work and the effort of the employees. Resting areas, dressing rooms, shower and toilets, waiting areas, cafeterias, canteens and first aid rooms should have sufficient temperature according to the purpose of usage; windows and ceiling lighting should prevent the adverse effects of the sun light depending on the workplace and the feature of the work done. - Inadequate Lighting Inadequate lighting causes poor visibility and thus increase in the occupational accidents. It is essential for the workplaces to be lightened by the day light sufficiently. Proper and sufficient lighting with artificial light should be provided when the situations in which people cannot benefit adequately from daylight due to the nature of the work or the construction type of the workplace or at the night shifts. Lighting systems in work places and passageways should not pose accident risk for the employees and should be placed properly. Spare lighting system that would provide emergency and sufficient lighting in case of any failure of the lighting system that may pose risk for the employees should be kept. - Slippery Surfaces Slippery surfaces can cause injuries as a result of falling. Thus; floor coverings and coatings should be firm, dry and as flat and nonslip as possible; there should not be dangerous slope, pits and obstacles; the surfaces should be made of the material suitable for cleaning that provides proper hygiene conditions. - Movement of Pedestrians and Vehicles The movements of the pedestrians and vehicles should be taken into consideration as they pose the risk of being hit and crashed. Regulations that would provide safe movement of the pedestrians and vehicles in the indoor and outdoor workplaces; there should be sufficient distance between roads and doors open to vehicular traffic and pedestrian passageways. The entry of people who are not authorized into the dangerous areas in which there is the risk of falling of material or employees depending on the features of the work done should be prevented with proper tools and equipment. Appropriate measures should be taken for the protection of the people who has the authority to enter the dangerous areas and those areas should be clearly indicated. - Lack of Check-ups of the Employees Check-up of the employees on a regular basis minimizes the risk of increase in the occupational diseases. The employees that do not get the health report from the Occupational Physician should not be allowed to work, periodic health checks of the hired employees should be made once every three months and the results should be included on the health reports. The ones who are found to be germ carrier by the check-up should receive treatment immediately and the ones who complete their treatment and cannot get a clean bill of health should not be allowed to work. The ones who has inflammatory disease, skin disease or diarrhea should be sent to the health institution for examination. - Boiler Room Inappropriate place of the boiler room or neglected boiler brings the risk of fire and explosion. Thus; all the boilers used in the workplace should be kept in a separate part or building resistant to fire and explosion and the workers should not be allowed to work on the floor above the boiler room. Ceiling of the boiler rooms should be high enough to facilitate working with the boiler when necessary, boiler rooms should be constantly ventilated and proper aspiration installation should be made when the ventilations is not enough by itself. Before mounting the boilers or in case of change and maintenance, they should be checked and proper and safe working condition of the boilers should be certified. Periodic maintenance should be made at least once a year and all maintenance and repairs should be recorded. The maintenance should be made after the experts take all kinds of security measures. RISKS IN THE FIELD OF RAW MATERIAL, DISCHARGE AND STORAGE - Trucks, wheat powder and compressors Major risks in raw material discharge area are freight trucks, wheat powder and compressor. Trucks can cause serious accidents due to the crashing or rollover during pulling up alongside of the lift. Therefore, there should be a guide to pull up the truck alongside of the wheat discharge area, the driver should wait in a safe area outside the vehicle during the lift is lifting the truck. Lifting machines and vehicles should be checked by the operators before starting to work each time and the operator should be allowed to control the machine from a safe distance. There should be stable chocks under the back of the tires in order that the truck does not slide back during the lifting process. Being highly exposed to wheat powder arising during the evacuation of the raw material can cause lung respiratory diseases. Therefore; the station in which the load is discharged should be closed enough to prevent the dust spreading around, there should not be any employee in this area during the load discharge and there should be proper aspiration system that vacuums the wheat powder from the environment in a short time. No one should enter into this area before the entire dust is cleaned. Compressor is an important risk factor that has the possibility of an explosion. Compressors should be stopped from a distant place in case of emergency. There should be safety valve in the air tanks of the compressors; the necessary precautions should be taken against the gas leaking from these valves and appropriate warning equipment reporting that safety valves are open. Special compressor oil that is specific to each compressor should be used, the tanks of the stable compressors should be in a durable division resistant to explosions and portable compressors should be kept at least 10 meters away from the employees or in a durable division. When the pressure in the compressors reach to the level set, the compressor motor should stop automatically; if the stopping of the motor delays, there should be safety equipment that would intervene to the pressure air. The speed regulators of the air compressors should be checked periodically, kept in a condition of working properly all the time and there should be equipment in which the flow of the cooling water can be seen. Stable compressors should intake fresh air; absorption of explosive, noxious and toxic gases, smoke and dust should be avoided. There should be oil and moisture separators between the air compressors and air tanks and these should not be taken off in any condition. When there is a stop valve on the outlet pipe of the air compressors, a safety valve should be placed between the compressor and this valve. Before the compressors are mounted and start to be used or in case of change and maintenance, they should be checked and it should be certified that they are working properly and safe. Periodical maintenance should be made at least once a year and all maintenance and repairs should be recorded. The maintenance should be made after the experts take all kinds of security measures. - Elevator and Conveying Transporters Elevator and conveying transporters have the risk of hand and arm injuries or losses for the employees. Therefore, employees should not put their hands or arms on the open parts of the elevator, should act from a safe distance, the protective parts should not be removed. The protectors that are disassembled during maintenance should be assembled before starting to be operated; the motion of the elevator shaft should be stopped completely in order for repairing the breakdown in case of blockage. During excessive heating, there should be a safety system that stops the motion of the elevator automatically. The materials sticking on the top cylinders or drums of the belt conveyors should not be cleaned by hand; they should be cleaned by proper knives or rotary brushes. Grounding should be made in order to prevent the formation of static electricity on the elevators and belt transporters. - Silos Silos can cause serious results such as injury, death and material damage in case of dust explosion. In order to be protected from these risks, welding and cutting should not be realized in the silos without taking sufficient precautions. Grain silo and storages should have dust-proof covers, waterproof coverings and air exchange assemblies. Grain drying parts should be made of fire resistant material; they should be placed at a sufficient distance from the elevators and storages or at suitably isolated places. During the maintenance, inside of the silos should be ventilated sufficiently and the employees working inside should be watched by other employees outside of the silos. Lightning conductor and grounding should be kept in the silos in case of static electricity formation or streak of lightning. Before starting to maintenance and repair; the power connection of the mixing equipment should be cut and the mixing equipment should be wedged, supported or tied up properly. Another risk factor in the silos is falling down from height. Therefore; the employees should use personal protective equipment such as seat belt, double-legged lanyard life rope, wire rope holder that prevents falling during the climbing to the silo stairs. During working on the top of the silo, employees should tie up themselves on a solid ground via personal protective belt. - Blending Machine Another risk factor in the storage is the blending machine that causes accidents such as hand or arm injury or loss. The protectors made for the machine should cover the all of the dangerous parts by cutting any contact during operation. Protectors should be made of fire and rust resistant material that does not need much maintenance; should be made of casting, sheet, tube or profile iron, wire mesh, wood, plastic or another material with proper strength and this material should not create danger by itself. Pulleys that are cracked or chipped should not be used in any way and the ones on the shaft should be removed. Transmission belt tensioner should be solidly made and tied in a way that it would prevent any accident in case of broken belt; it should not include attachments and if it does, the attachment parts should be solidly tied up with stitching, rivets and special fasteners. RISKS IN THE FIELD OF PRODUCTION There are general risks such as electrical leakage, receiving electric shock, lack of fire extinguishing systems or that they are not placed to be easily reached and being neglected, lack of warning and alert signs, unsuitable hygiene conditions among the risk in the field of production just like throughout the plant. These risks are discussed shortly in the previous section. Similar precautions are valid for the production. However, production field has also specific risks. - Electrical Leakage in the Machines If the machine has power supply, all the hazards arising from electricity should be prevented. For that; electrical installation should be insulated inside the conduit, the trunk grounding of the machines should be made and insulating mats should put under the operating parts of the machine. - Inadequate Machine Protectors The protectors in the machines are significantly important as they carry the risk of flying object and arm or hand injury or loss. These protectors should be solidly made, should not create additional hazards, should not be easily removed or inactivated and should be placed at enough distance from the hazard area. Besides the protectors should not limit the vision of the equipment operation points more than the required amount, it should only limit the access of the operation area and part assembly or disassembly or the necessary actions for maintenance should be done without removing the protectors. - Rollers and Intensive Dampener Machines Rollers and intensive dampener machines carry the risks of injury or loss of arms or hands and hearing loss due to the excessive loss. In order to minimize these risks, switch and the control buttons on the machine should be made in shape and functionality that do not move the machine spontaneously or with any hit and should be placed in the areas where workers can easily use. When an employee has to work on some parts of a machine or counter, this counter should include multiple stop and one operation buttons. If there are more than one electric motors on a machine and counter, the counter should have a main switch or one or more stop button that stops the entire operation of the counter and the operations button should be in green and the stop buttons should be in red. Besides the separate stop devices of a machine or counter in a workshop, a main switch or another device that would stop the machine and counters completely in the workshop or area should be kept. All the moving parts and transmission equipment of drive machinery and the dangerous parts of the machines should be protected properly; putting hands into the dangerous parts of the machine should be prevented and each machine should be grounded separately. Removal or making useless of the transmission equipment, protectors of the counter and machines, safety devices and equipment are forbidden. These protectors should only be removed during control, adjustment, maintenance and repair and should be put again as soon as these activities are completed. In case of breakdown in a counter or machine or determining a fault or insufficiency on the protectors of these, the machine and the counter should be stopped immediately and precautions that prevent other people’s working on these machine or counters should be taken by informing the authorized persons. Transmission belt tensioner should be solidly made and tied up in a way that would prevent accidents in case of broken belt. These belts should not be directly transferred by hand, removed or put, resining of them should be made on the part where the belt is separated from the pulley and that should not be done by hand directly. Transmission bearings should be placed on a parallel axes, should be properly maintained and should not be lubricated during operation. The oiler and grease should not be placed on the dangerous parts of the bearings that are not easily accessed and the inlets of these should be extended to the places without danger and easily accessed. If lubrications are needed to be done during operation technically, special hand oilers with long inlets should be used. In order to prevent issues like hearing loss due to excessive noise, general health examinations of the employees working in the noisy environments should be done periodically and if reduction in the case of hearing or any other disorder is determined, these people should receive treatment. Besides employees who have ear and nerve disease or hypertension should not work in the noisy areas and should receive treatment. The employer should provide ear protectors for the employees and these should be ready for use. When the noise exceeds the maximum level, these earphones should be used. The earphones should eliminate or decrease the risk about hearing to minimum. The employer should make every effort for providing the usage of the ear protectors and check the efficiency of the precautions to be taken. - Pneumatic Fans and Screens Pneumatic fans can cause serious problems like fire and explosion. In order not to have these issues, the ducts or pipes used in the aspiration installment should be made of fireproof material and spiral or tilting hoses should be used on the portable absorption inlets of these systems. The pipes and ducts should be made according to techniques; they should be attached and tied up solidly on the vents. If there are flammable or combustible materials inside the absorbed air; the duct, hub and trunk of the aspirator propeller should not be made of iron or steel material; the propeller bearing should be lubricated well and dust-proof and solid wire mesh should be put on the exhaust vents. Electric motors of the aspirators should be suitable for its environment; if there are flammable and combustible substances in the absorbed air, motor should be mounted properly against the flammable and combustible substances or made of material resistant to these substances. Daily maintenance and cleaning should be made and general check-up and cleaning should also be made every three months; the characteristics of the installation should not be damaged after the repairs. Screen can cause risks like catching onto and falling. Therefore, there should be railings that would prevent to get much closer to the screens in the screen floor from a specific distance. Besides, while the machines are being operated, only authorized persons should enter this area. RISKS IN THE AREA OF PACKING AND LOADING - Packaging Machinery and Conveyor Belts Packaging machinery and conveyor belts can cause injury or limb loss. Therefore, the employees should be trained and each of them should use personal protectors. The rotary parts of the conveyors should be covered in order to prevent putting arm or hand. The materials sticking on the top cylinders or drums of the belt conveyors should not be cleaned by hand; they should be cleaned by proper knives or rotary brushes. When there is an opening over 15 centimeters between the rollers of roller conveyors; they should be covered with proper and resistant covers made of metal, wood or another material and the shafts and bend gears should be protected properly. When the transporters are in the pits or at ground level, these and the openings should be protected with railings and plinths. In case the belts are broken loose from the belt transporters, proper protectors should be used and these should be extended at least 1 meter from the both ends of the cylinder. In order to prevent problems like electric shocking in the belt conveyors; the damaged cables should be changed, the control device should be hanged on an appropriate place and it should not be left in the wet environments. System grounding of the electric installation should be made and proper personal protectors (insulating gloves) should be supplied and used. - Sack Filling Machines Sack filling machines threaten the employees with lung and respiratory tract disorders arising from being exposed to excessive flour dust. In this area, the front of the filler pipe in the sack filling machines should be covered with preferably transparent and hinged covers. - Manual Handling Manual handling can cause muscle and skeleton system diseases as it forces employees physically. Necessary precautions should be taken in the workplaces in order to make work organization in a way that the load does not need to be handled by hand and to provide that the load is handled by proper methods and especially by using mechanical systems. INTERNATIONAL STANDARDS IN THE OCCUPATIONAL SAFETY The occupational safety risks discussed so far and the issues to be considered for minimizing these risks includes only a small and basic part of the risks to be encountered and the precautions to be taken in a flour mill or any other production workshop. Besides these, there are many risk factors and risk control methods that are not mentioned above. Therefore the companies that care the occupational safety or obligate to apply the occupational safety system due to the legal regulations get support from the experts and apply various international standards in order not to skip any point. Although there are specific legal regulations and standards on occupational safety for different occupational groups in each country, the most widely accepted system on the international scale is OHSAS 18001 standard prepared by British Standards Institute. OHSAS is a management model that envisages keeping the risks, which may affect the health and safety of the employees in the workplaces, under control systematically. You can find the significant basic sections of the OHSAS standard on the following pages.  
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