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Pushing & Pulling - Handcarts
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Are there hazards associated with using hand carts?
What should I consider when selecting a hand cart?
What should I know about handling the carts?
What other factors influence the amount of weight than can be on a cart?
Are there hazards associated with using hand carts? The use of hand carts to transport loads instead of carrying them saves workers a lot of effort. It decreases the risk of overexertion injury in jobs that include manual materials handling. Pushing, pulling, and maneuvering hand carts, however, still involve some of the old hazards (overexertion) and create new ones. The most common injuries that result from hand cart operations are: - fingers and hands being caught in, on, or between the cart and other objects,
- toes, feet and lower legs being bumped or crushed by the cart, and
- strained arms, shoulder and back muscles and joints.
What should I consider when selecting a hand cart? Good design of the workplace and the selection of a hand cart suitable for the task can reduce the risk of injury of any kind. Points to consider when selecting carts include: - expected load (weight, size, shape),
- frequency of use,
- distances to cover,
- work area characteristics (aisle width, type of flooring), and
- type of wheels or casters.
There are currently no numerical standards on acceptable loads or forces required while operating hand carts. Recommendations presented in Table 1 are adopted from guidelines developed by the Ergonomics Group of Eastman Kodak Co. who compiled data from various studies. General recommendations for selection are: - the load on two-, three-, and four- wheel hand carts should not exceed 200 Kg (approximately 450 lbs)
- the load on hand pallet carts can be up to approximately 700 Kg (1500 lbs)
- manual carts should not be used more than 200 times a work day
- the load should not be transported more than 30-35 meters (about 100 feet) per "shipment"
Where there is a need to move heavier loads over longer distances, using powered trucks or a powered conveyor system should be considered. Table 1
Recommended Limits in the Selection of
Hand and Powered Trucks and Carts |
Type of Truck or Cart | Maximum Load | Maximum Transport Distance | Maximum Frequency Units (per 8 hr - shift) | Minimum Aisle Width | Type of Transfer to and from Truck (+) | | kg | lb | m | ft | m | ft | | 2-wheeled hand cart | 114 | 250 | 16 | 50 | 200 | 1.0 | 3 | Ma, P | | 3-wheeled hand cart | 227 | 500 | 16 | 50 | 200 | 1.0 | 3 | Ma, P | | 4-wheeled hand cart | 227 | 500 | 33 | 100 | 200 | 1.3 | 4 | Ma, P | | Hand pallet truck | 682 | 1500 | 33 | 100 | 200 | 1.3 | 4 | Me, UL | | Electric pallet truck | 2273 | 5000 | 82 | 250 | 400 | 1.3 | 4 | Me, UL | | Electric hand-jack lift truck | 2273 | 5000 | 33 | 100 | 400 | 1.3 | 4 | Me, UL | | Power low lift truck | 2273 | 5000 | 328 | 1000 | 400 | 2.0 | 6 | Me, P, UL | | Electric handstacking truck | 682 | 1500 | 82 | 250 | 400 | 1.3 | 4++ | Me, UL | | Power fork truck | 2273 | 5000 | 164 | 500 | 400 | 2.0 | 6++ | Me, UL | + Ma = Manual; Me = Mechanical; P = Parts; UL = Unit Load ++ These trucks have tiering capability. In order to use it, ceiling must be more than 4 m (12 ft) high. Adapted from: Ergonomic Design for People at Work : Vol. 2, by Eastman Kodak Company. Van Nostrand Reinhold, 1986. What should I know about handling the carts? There are no guidelines for forces needed to operate a cart or truck other than the suggestions in Table 1 on how heavy a load can be moved. It is important to be aware that the forces in these tables are not the same as the weight of objects being pushed or pulled. They indicate the amount of force that a worker can exert safely. This restricts the direct application of the recommended limits for weight limits that can be pushed or pulled in the workplace. Only trained personnel using special equipment can measure the forces exerted by a worker. Operating a cart involves three components: starting, maintaining in motion and stopping. Each of these is limited differently: - starting - up to 225 N (25 Kgf or 55 lbf)
- maintaining in motion - up to 120 N (approximately 15 Kgf or 30 lbf) for 1 min.
- stopping (within 1 meter) - up to 360 N (40 Kgf or 90 lbf)
What other factors influence the amount of weight than can be on a cart? There are certain conditions that should be examined in order to modify the above limits. Floors that are in poor shape (cracked, etched, uneven) make operating carts more difficult. The remedy for this situation is to use a cart with bigger wheels or to reduce the load. If ramps are used, the limits must be lowered. Complicated maneuvering calls for a considerably lower limit, particularly where there is not enough space to get one's body weight behind the cart. It is also recommended that the cart should not exceed the speed of a person's walking pace (3-4 km/h or about 1.9 - 2.5 mph). Modifying force limits for pushing, pulling or maneuvering for any given work situation is essential not only for the safety of the operator but also for other workers within the work area.
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Document last updated on November 27, 1997
Copyright ©1997-2008 Canadian Centre for Occupational Health & Safety
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