102 – Safety Engineering -1
Mechanical material handling
What should your employees know before moving, handling, and storing materials?
What are the precautions to be taken while handling equipment?
What are the potential hazards for workers?
What precautions should workers take when moving materials manually?
What precautions should workers take when moving materials mechanically?
What precautions must workers take to avoid storage hazards?
What safeguards must workers follow when stacking materials?
What safety measures should employers take regarding conveyors?
What safety measures should employers take regarding cranes?
What must employers do to ensure the safe use of slings?
What must employers do to protect workers who operate powered industrial trucks?
What are the safety requirements for design?
What are the safety requirements for modification?
What are the safety requirements for modification?
What safety precautions should employers and workers observe when operating or maintaining powered industrial trucks?
Are there any training requirements for operators of powered industrial trucks?
Basic Safety and Health Principles?
What is ergonomics?
Introduction
Handling and storing materials involve diverse operations such as hoisting tons of steel with a crane; driving a truck loaded with concrete blocks; carrying bags or materials manually; and stacking palletized bricks or other materials such as drums, barrels, kegs, and lumber.
The efficient handling and storing of materials are vital to industry. In addition to raw materials, these operations provide a continuous flow of parts and assemblies through the workplace and ensure that materials are available when needed. Unfortunately, the improper handling and storing of materials often result in costly injuries.
What are the precautions to be taken while handling equipment?
5 safety precautions to consider when operating lifting equipment
Always check equipment over before you use it.
Stow cranes properly for transit.
Never position yourself underneath the load.
Don't work on a truck bed.
Ensure that your training is up to date.
What are the potential hazards for workers?
▪ Strains and sprains from lifting loads improperly or from carrying loads that are either too large or too heavy,
▪ Fractures and bruises caused by being struck by materials or by being caught in pinch points, and
▪ Cuts and bruises caused by falling materials that have been improperly stored or by incorrectly cutting ties or other securing devices.
What precautions should workers take when moving materials manually?
When moving materials manually, workers should attach handles or holders to loads. In addition, workers should always wear appropriate personal protective
equipment and use proper lifting techniques. To prevent injury from oversize loads, workers should seek help in the following:
▪ When a load is so bulky that employees cannot properly grasp or lift it,
▪ When employees cannot see around or over a load, or
▪ When employees cannot safely handle a load.
Using the following personal protective equipment prevents needless injuries when manually moving materials:
▪ Hand and forearm protection, such as gloves, for loads with sharp or rough edges.
▪ Eye protection.
▪ Steel-toed safety shoes or boots.
▪ Metal, fibre, or plastic metatarsal guards to protect the instep area from impact or compression.
Employees should use blocking materials to manage loads safely. Workers should also be cautious when placing blocks under a raised load to ensure that the load is not released before removing their hands from under the load. Blocking materials and timbers should be large and strong enough to support the load safely. In addition to materials with cracks, workers should not use materials with rounded corners, splintered pieces, or dry rot for blocking.
What precautions should workers take when moving materials mechanically?
Using mechanical equipment to move and store materials increases the potential for employee injuries. Workers must be aware of both manual handling safety concerns and safe equipment operating techniques. Employees should avoid overloading equipment when moving materials mechanically by letting the weight, size, and shape of the material being moved dictate the type of equipment used. All materials-handling equipment has rated capacities that determine the maximum weight the equipment can safely handle and the conditions under which it can handle that weight. Employers must ensure that the equipment-rated capacity is displayed on each piece of equipment and is not exceeded except for load testing.
Although workers may be knowledgeable about powered equipment, they should take precautions when stacking and storing material. When picking up items with a powered industrial truck, workers must do the following:
▪ Centre the load on the forks as close to the mast as possible to minimize the potential for the truck tipping or the load falling,
▪ Avoid overloading a lift truck because it impairs control and causes tipping over,
▪ Do not place extra weight on the rear of a counterbalanced forklift to allow an overload,
▪ Adjust the load to the lowest position when travelling,
▪ Follow the truck manufacturer's operational requirements, and
▪ Pile and cross-tier all stacked loads correctly when possible.
What precautions must workers take to avoid storage hazards?
Stored materials must not create a hazard for employees. Employers should make workers aware of such factors as the materials' height and weight, how accessible the stored materials are to the user, and the condition of the containers where the materials are being stored when stacking and piling materials. To prevent creating hazards when storing materials, employers must do the following:
▪ Keep storage areas free from accumulated materials that cause tripping, fires, or explosions, or that may contribute to the harboring of rats and other pests;
▪ Place stored materials inside buildings that are under construction and at least 6 feet from hoist ways, or inside floor openings and at least 10 feet away from exterior walls;
▪ Separate non-compatible material; and
▪ Equip employees who work on stored grain in silos, hoppers, or tanks, with lifelines and safety belts.
In addition, workers should consider placing bound material on racks, and secure it by stacking, blocking, or interlocking to prevent it from sliding, falling, or collapsing.
What safeguards must workers follow when stacking materials?
Stacking materials can be dangerous if workers do not follow safety guidelines. Falling materials and collapsing loads can crush or pin workers, causing injuries or
death. To help prevent injuries when stacking materials, workers must do the following:
▪ Stack lumber no more than 16 feet high if it is handled manually, and no more than 20 feet if using a forklift;
▪ Remove all nails from used lumber before stacking;
▪ Stack and level lumber on solidly supported bracing;
▪ Ensure that stacks are stable and self-supporting;
▪ Do not store pipes and bars in racks that face main aisles to avoid creating a hazard to passersby when removing supplies;
▪ Stack bags and bundles in interlocking rows to keep them secure; and
▪ Stack bagged material by stepping back the layers and cross-keying the bags at least every ten layers (to remove bags from the stack, start from the top row first).
During materials stacking activities, workers must also do the following:
▪ Store baled paper and rags inside a building no closer than 18 inches to the walls, partitions, or sprinkler heads;
▪ Band boxed materials or secure them with cross-ties or shrink plastic fiber;
▪ Stack drums, barrels, and kegs symmetrically;
▪ Block the bottom tiers of drums, barrels, and kegs to keep them from rolling if stored on their sides;
▪ Place planks, sheets of plywood dunnage, or pallets between each tier of drums, barrels, and kegs to make a firm, flat, stacking surface when stacking on end;
▪ Chock the bottom tier of drums, barrels, and kegs on each side to prevent shifting in either direction when stacking two or more tiers high; and
▪ Stack and block poles as well as structural steel, bar stock, and other cylindrical materials to prevent spreading or tilting unless they are in racks.
In addition, workers should do the following:
▪ Paint walls or posts with stripes to indicate maximum stacking heights for quick reference;
▪ Observe height limitations when stacking materials;
▪ Consider the need for availability of the material; and
▪ Stack loose bricks no more than 7 feet in height. (When these stacks reach a height of 4 feet, taper them back 2 inches for every foot of height above the 4-foot level. When masonry blocks are stacked higher than 6 feet, taper the stacks back one-half block for each tier above the 6-foot level.)
Important Safety Measures
To reduce the number of accidents associated with workplace equipment, employers must train employees in the proper use and limitations of the equipment they operate. In addition to powered industrial trucks, this includes knowing how to safely and effectively use equipment such as conveyors, cranes, and slings.
What safety measures should employer stake regarding conveyors?
When using conveyors, workers may get their hands caught in nip points where the conveyor medium runs near the frame or over support members or rollers. Workers also may be struck by material falling off the conveyor, or they may get caught in the conveyor and drawn into the conveyor path as a result. To prevent or reduce the severity of an injury, employers must take the following precautions to protect workers:
▪ Install an emergency button or pull cord designed to stop the conveyor at the employee's work station.
▪ Install emergency stop cables that extend the entire length of continuously accessible conveyor belts so that the cables can be accessed from any location along the conveyor.
▪ Design the emergency stop switch so that it must be reset before the conveyor can be restarted.
▪ Ensure that appropriate personnel inspect the conveyor and clear the stoppage before restarting a conveyor that has stopped due to an overload.
▪ Prohibit employees from riding on a materials-handling conveyor.
▪ Provide guards where conveyors pass over work areas or aisles to keep employees from being struck by falling material. (If the crossover is low enough for workers to run into it, mark the guard with a warning sign or paint it a bright color to protect employees.)
▪ Cover screw conveyors completely except at loading and discharging points. (At those points, guards must protect employees against
contacting the moving screw. The guards are movable, and they must be interlocked to prevent conveyor movement when the guards are not in place.)
What safety measures should employer stake regarding cranes?
Employers must permit only thoroughly trained and competent workers to operate cranes. Operators should know what they are lifting and what it weighs. For example, the rated capacity of mobile cranes varies with the length of the boom and the boom radius. When a crane has a telescoping boom, a load may be safe to lift at a short boom length or a short boom radius, but may overload the crane when the boom is extended and the radius increases.
To reduce the severity of an injury, employers must take the following precautions:
▪ Equip all cranes that have adjustable booms with boom angle indicators.
▪ Provide cranes with telescoping booms with some means to determine boom lengths unless the load rating is independent of the boom length.
▪ Post load rating charts in the cab of cab-operated cranes. (All cranes do not have uniform capacities for the same boom length and radius in all directions around the chassis of the vehicle.)
▪ Require workers to always check the crane's load chart to ensure that the crane will not be overloaded by operating conditions.
▪ Instruct workers to plan lifts before starting them to ensure that they are safe.
▪ Tell workers to take additional precautions and exercise extra care when operating around power lines.
▪ Teach workers that outriggers on mobile cranes must rest on firm ground, on timbers, or be sufficiently cribbed to spread the weight of the crane and the load over a large enough area. (Some mobile cranes cannot operate with outriggers in the traveling position.)
▪ Direct workers to always keep hoisting chains and ropes free of kinks or twists and never wrapped around a load.
▪ Train workers to attach loads to the load hook by slings, fixtures, and other devices that have the capacity to support the load on the hook.
▪ Instruct workers to pad sharp edges of loads to prevent cutting slings.
▪ Teach workers to maintain proper sling angles so that slings are not loaded in excess of their capacity.
▪ Ensure that all cranes are inspected frequently by persons thoroughly familiar with the crane, the methods of inspecting the crane, and what
can make the crane unserviceable. Crane activity, the severity of use, and environmental conditions should determine inspection schedules.
▪ Ensure that the critical parts of a crane—such as crane operating mechanisms, hooks, air, or hydraulic system components and other load-carrying components—are inspected daily for any maladjustment, deterioration, leakage, deformation, or other damage.
What must employers do to ensure the safe use of slings?
As an employer, you must designate a competent person to conduct inspections of slings before and during use, especially when service conditions warrant. In addition, you must ensure that workers observe the following precautions when working with slings:
▪ Remove immediately damaged or defective slings from service.
▪ Do not shorten slings with knots or bolts or other makeshift devices.
▪ Do not kink sling legs.
▪ Do not load slings beyond their rated capacity.
▪ Keep suspended loads clear of all obstructions.
▪ Remain clear of loads about to be lifted and suspended.
▪ Do not engage in shock loading.
▪ Avoid sudden crane acceleration and deceleration when moving suspended loads.
What must employers do to protect workers who operate powered industrial trucks?
Workers who handle and store materials often use fork trucks, platform lift trucks, motorized hand trucks, and other specialized industrial trucks powered by electrical motors or internal combustion engines. Employers must make these workers aware of the safety requirements pertaining the design, maintenance, and use of these trucks.
What are the safety requirements for design?
All new powered industrial trucks, except vehicles intended primarily for earth moving or over-the-road hauling, must meet the design and construction requirements for powered industrial trucks established in the American National Standard for Powered Industrial Trucks, Part II, ANSI B56.1-1969. Trucks approved for fire safety also must bear a label, or some other identifying mark, indicating acceptance by a nationally recognized testing laboratory.
What are the safety requirements for modification?
You and your employees must not make modifications and additions affecting capacity and safe operation of the trucks without the manufacturer's prior written approval. In these cases, you must change capacity, operation, and maintenance instruction plates and tags or decals to reflect the new information. If the truck is equipped with front-end attachments that are not factory installed, the user must request that the truck be marked to identify these attachments and show the truck's approximate weight— including the installed attachment—when it is at maximum elevation with its load laterally centred.
What safety precautions should employers and workers observe when operating or maintaining powered industrial trucks?
When operating or maintaining powered industrial trucks, you and your employees must consider the following safety precautions:
Fit high-lift rider trucks with an overhead guard if permitted by operating conditions.
Equip fork trucks with vertical load backrest extensions according to manufacturers' specifications if the load presents a hazard.
Locate battery-charging installations in designated areas.
Provide facilities for flushing and neutralizing spilled electrolytes when changing or recharging batteries to prevent fires, to protect the charging apparatus from being damaged by the trucks, and to adequately ventilate fumes in the charging area from gassing batteries.
Provide conveyor, overhead hoist, or equivalent materials handling equipment for handling batteries.
Provide auxiliary directional lighting on the truck where general lighting is less than 2 lumens per square foot.
Do not place arms and legs between the uprights of the mast or outside the running lines of the truck.
Set brakes and put other adequate protection in place to prevent movement of trucks, trailers, or railroad cars when using
powered industrial trucks to load or unload materials onto them.
Provide sufficient headroom under overhead installations, lights, pipes, and sprinkler systems.
Provide personnel on the loading platform with the means to shut off power to the truck whenever a truck is equipped with vertical only (or vertical and horizontal) controls elevatable with the lifting carriage or forks for lifting personnel.
Secure dock boards or bridge plates properly so they won't move when equipment moves over them.
Handle only stable or safely arranged loads.
Exercise caution when handling tools.
Disconnect batteries before repairing electrical systems on trucks.
Ensure that replacement parts on industrial trucks are equivalent to the original ones.
What Is Ergonomics?
Ergonomics is defined as the study of work and is based on the principle that the job should be adapted to fit the person rather than forcing the person to fit the job. Ergonomics focuses on the work environment, such as its design and function, as well as items—such as the design and function of work stations, controls, displays, safety devices, tools, and lighting to fit the employees' physical requirements and to ensure their health and well being.
Ergonomics includes restructuring or changing workplace conditions, to make the job easier, and reducing stressors that cause musculoskeletal disorders. In the area of materials handling and storing, ergonomic principles may require controls such as reducing the size or weight of the objects lifted, installing a mechanical lifting aid, or changing the height of a pallet or shelf.
Although no approach eliminates back injuries resulting from lifting materials, you can prevent a substantial number of lifting injuries by implementing an effective ergonomics program and by training your employees in appropriate lifting techniques.
