Agriculture Case Study - Manual handling
Problems and solutions
In agriculture, back, neck and limb disorders are the most common types of ill health. Many of the injuries are caused or made worse by poor manual handling practice. They can arise from stresses and strains over a period of time rather than from a single event.
Handling spare and dual tractor wheels
Spare tractor wheels are heavy, awkward loads that are frequently moved, eg when fitting dual wheels or as part of changing between conventional, row crop and low ground pressure sizes. The effort needed to roll the wheel when it is vertical can be deceptively small but, once the wheel starts to lean, it quickly becomes unstable and a major manual handling problem.
The risk of injury is even greater when you have to align wheel studs and can be increased by the ground surface where the wheels are handled. It is tempting for one person to try to do the job alone and often people will leave wheels leaning against a wall when they have finished, making the next move possible but causing unacceptable risks to children.
Use a mechanical wheel handler, either as a free-standing unit or as an attachment on a lift truck. Wheel handlers can lift, carry, rotate and tilt wheels to aid fitting and removal from the tractor. See Figure 1.
Handling bagged products
Even though most feed and fertiliser is now handled in bulk or big bags that can be moved mechanically, there are still some 40kg and 50kg bags used, eg with seed corn.
Where it is not feasible to change to bulk or big bag systems, eg with some specialist, small-volume fertilisers or on smaller farms with limited mechanisation, considerable amounts of lifting can be required.
Handling materials in 50kg bags into a high hopper, such as on a seed drill or up steps into a loft, involves increased risks. Where there is a poor working surface, eg slippery concrete or freshly cultivated soil, the problems are worse.
- Use big bags or bulk systems with loaders, pipelines or augers to move the material wherever possible.
- Tote bins can help to mechanise and reduce manual effort.
- Aim to use the optimum spreader or drill hopper size for the scale of your enterprise to increase the opportunities for bulk systems.
- Palletise 50kg bags wherever and for as long as possible. Aim to keep the pallets intact from lorry to store, to trailer, to spreader or drill.
- Use the height of delivery trailers to your advantage so that bags are presented at the best height for carrying.
- Position trailers and spreaders or drills so that bags can be moved to the hopper in one movement, avoiding difficult access over coulters etc.
- If you do have to move bags or bulk material by hand, especially over uneven or muck-laden ground, consider trolleys and feed barrows which have larger wheels and pneumatic tyres, or which are motorised. See Figure 2.
Lifting chemical and oil containers
Despite many pesticide formulations becoming less bulky, some packs of liquid products delivered onto farms are still difficult to handle, particularly into stores and other buildings. Some containers which provide excellent control of chemical risks through closed transfer technology can cause manual handling problems if you don't properly plan how you will move them – and use the right equipment, eg for handling and agitation. Larger (eg 200 litre) oil or dairy chemical drums avoid much manual handling but still have to be moved from a delivery lorry to where they will be used.
- Use a drum cradle to move and tilt larger containers. See Figure 3.
- Plan your storage arrangements to reduce the distance containers have to be moved.
- Install ramps at the entrance to chemical stores to allow rolling of containers.
- Use bulk containers that are only handled by a lift truck.
- Fit low-level filling points on sprayers – never lift large containers up a ladder to the top lid.
- Use automated dairy bulk-tank washers to reduce chemical handling.
- Always consider pumps, siphons or gravity taps to remove the contents.
- Use the manual handling risk as one of your criteria when deciding which chemical formulation is most appropriate for your farm.
Handling and casting sheep
Handling sheep regularly for routine flock management involves a lot of manual effort. One example is casting adult sheep for foot trimming. The risks arise both from the effort in turning the sheep and then from the awkward posture reaching down to the animal.
As with many risks, avoiding the job or doing it less often is the preferred solution, eg avoid introducing footrot: vaccinate, use a footbath or, where possible, allow access to stony ground. However, where sheep have to be cast, and especially where this involves a group of animals, a turnover crate will reduce the manual handling risks. A turnover crate can also be used in conjunction with a handling system to aid the flow of animals, enable shedding and, with some, present the sheep on an elevated platform to reduce bending when drenching, dagging etc (see Figure 4). A number of different designs are available.
Consider a turnover crate and handling system to:
- present the sheep at the right height and the right way up;
- make sheep struggle less;
- avoid lifting forces – good designs rotate without raising the sheep's centre of gravity too much;
- avoid sitting sheep on dirty ground, contaminating wool and risking flystrike.
Shearing is a high-risk job involving the entire adult flock for a short time and requiring substantial manual effort. While contractors shearing many thousands of sheep may be considered at higher risk, often a farmer who is less practised at the job will have a poorer technique and work in less suitable surroundings.
Traditionally, the physical options for reducing the risks during shearing have been limited to the workstation layout. The best practice of presenting sheep to the shearer in a close, small pen and allowing rapid exit of the shorn animal, away from the wrapping point, has been achieved in purpose-designed shearing sheds or mobile shearing trailers. However, these features can be employed at any shearing site.
Manual effort can be further reduced by a shearing back-aid (see Figure 5). Back-aids are widely used in Australia and in other sheep-rearing countries and are available in the UK. The 'Warrie back-aid'® helps by carrying some of the shearer's upper body weight while they are bent over the sheep.
The device uses sound ergonomic principles and in a well-designed workplace can make the difference between lifelong back problems and years of skilled shearing.
Many farming systems involve handling hay, silage or straw bales. The most important step is to match the optimum bale type to your available storage and system of use. While silage bales will normally be handled entirely mechanically, others may not.
If you cannot use larger bales, eg if you farm a smaller unit or, as in some parts of the country where the fields, storage facilities and methods of using hay or straw would not support bigger bales, you need to make sure you have controlled the risks properly.
- Transporting, putting into store and using conventional bales on small units, eg where bales are stored in small stone barns, lofts etc.
- Outdoor stacks with bales which are spoiled by rain and very heavy.
- Handling small bales into straw choppers with a high hopper (necessary to protect against contact with blades).
- Moving pedestrian bale choppers around the farm.
- Use traditional aids such as pitchforks, bale hooks or slat elevators.
- Store bales close to where you will use them, eg over livestock pens.
- Use sledges, accumulators, grabs and other mechanical aids to handle bales in groups, where possible.
- Try to use storage buildings which allow easy access for a materials handler or accumulator trailer.
- Where possible, switch to large-bale systems.
Round and large square bales
While most handling will be mechanical, these bales sometimes have to be moved by hand, eg in livestock pens.
- Unrolling round bales in less suitable livestock pens, especially when turning corners.
- Restricted access into buildings such as cubicle sheds.
- Playful cattle can be an additional hazard and may need to be excluded if you have to go into the pen.
- When large square bales of poor-quality straw are cut, the flakes can themselves be very heavy.
- Use chopped straw from a tractor-mounted chopper. See Figure 6.
- Consider an automated unwrapper or other mechanised feeding process. See Figure 7.
- Use a purpose-designed carrier – effectively fitting wheels to the bale.
- Use a loader attachment that allows large square bales to be gradually released for bedding yards.
- Break open bales outside areas with restricted access and move the flakes on a trailer or trolley with large wheels.
- Consider alternative bedding systems using wood shavings, rubber mats or water beds in cubicles.