Serious and fatal accidents can arise from work activities associated with incorrect stacking and unsafe storage of bales. With harvest around the corner, it is worth refreshing yourself with the guidance below to keep everyone safe around stacked bales.
Where to stack bales
- Anyone stacking bales should know how to do so safely, or they should be directly supervised by someone with this knowledge.
- Bale stacks must be built on firm, dry, level, freely draining ground which should be open and well-ventilated and away from overhead power lines.
- Use stones or crushed rock on the ground beneath a stack to make it level. This may also help trap water and prevent it going into the stack.
- Select a site away from any potential fire hazards and sources of ignition.
- Good road access is beneficial so bales can be transported to and from the stack safely.
- Sufficient space should be provided to allow tractors, trailers, and other vehicles adequate room to manoeuvre.
- The need to fence-off stacks should be assessed if livestock have access, or if the stack is close to a footpath or boundary.
- If it is not possible to build stacks away from areas where the public have access, provide signs to warn people to keep clear (e.g., risk of falling bales, fire etc)
Big square / high-density bales
Stacks of big square bales are more stable than stacks of small conventional bales, but they can cause fatal and serious injuries if they fall on a person due to their weight and size.
Stacks should be constructed with:
- A wide base that narrows slightly as it gets higher.
- Alternating layers of single or double bales that ‘tie in’ those below, i.e., there should be an overlap of half a bale width all round to add enough stability and strength to stop the stack from splitting. This is especially important if stacks are close to public roads, footpaths or in an area where people may be present.
Big square / high-density bale stacks should not be built higher than:
- One-and-a-half times the width of the base.
- The reach of the equipment available to de-stack it.
- Ten bales on hard-standing or concrete.
- Eight bales on sites where no hard standing is available.
Small square / conventional bales
Small bales should be interlocked closely, with alternate layers rotated and slightly offset so that each bale is locked in, e.g., in a pattern similar to brickwork.
The part of the stack from where bales will be removed when required for use should be built in ‘steps’ to allow safe access for stacking and de-stacking. However, this may also provide easy access for children and so it may be necessary to block up the steps by leaving a few bales in place until access is needed.
Round bales
The safest method of stacking round bales is on their sides in a pyramid but ensure that:
- The bottom rows of outside bales are chocked or fitted with stakes or supports.
- Layers are overlapped by half a bale front to end.
Stacking round bales on their ends can lead to unstable stacks because inconsistent bale densities allow bales to settle and shift. Only consider stacking round bales on their ends if they are stored in a building with walls or other suitable measures to reduce the risk of bales collapsing.
Example bale stacking patterns:
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| Big square / high-density bales | Small square bales | Round bales |
Further guidance from the HSE on safe working with bales in agriculture is available here: Safe working with bales in agriculture INDG125 (hse.gov.uk)
