The NFU Mutual, which deals with hundreds of harvest-time machinery fires each year, says even wet harvests bring fires because of the extra strain on machinery - in particular overheating bearings. It advises the following pre-harvest checks:

• Look for vermin and corrosion damage from over the winter, which can lead to problems on start up - even on combines which received a thorough post-harvest clean-up and service
• Keep a close watch for the first few minutes of running. This can prevent overheating or a short circuit that could cause a fire to break out before the machine has even got to the field
• If it's the first start-up of the summer, don't leave the combine warming up next to a shed while you have breakfast. The NFU Mutual says many fires break out at this early point
• Most combines have extinguishers on hand to deal with combine fires but they should be regularly tested to ensure they are fit for use. Also, do you and your staff know how to use them?
• Trim overgrown hedges around field entrances, especially where they are accessed from a public road
• Keep it clean. You can never overdo the cleaning out of dust and chaff from hot spots
• Resist the urge to keep going when the temperature gauge is in the red
• Never try to clear blockages or carry out maintenance with the machine still running. Taking short cuts here regularly leads to horrific injuries and deaths
• Power lines. Forgetting that the kit you are using is taller than the machine it replaced has led to a number of electrocutions. Other accidents have resulted from power lines sagging and hitting machines that passed underneath safely the previous year
• In very dry conditions, keep a sprayer filled with water on hand attached to a tractor to lay a fire break in the event of a crop fire
• If there are young children on the farm, keep them well away from working areas
• Grain drier fires are common, too, so it's important to clean dust off regularly