There is better understanding of the heat risks facing livestock than there is of the hot weather threat to the agricultural workers who care for them.

So said the British Occupational Hygiene Society which, as the thermometers tilt towards a record-breaking 40 degrees in parts of the UK, has called for greater awareness of the risks to agricultural workers during heatwaves.

The Society has highlighted the direct impact of heat stress on the human body – workers not acclimatised to working in heat or without hydration and shade run the risk of heat exhaustion, which can manifest as fatigue, giddiness, nausea and headaches.

“With seasonal workers operating over long shifts over the summer harvest period, the combination of heat exhaustion and the operation of farm machinery is a recipe for expensive and potentially dangerous mistakes,” said BOHS president Chris Keen. “With record temperatures and pressure on to harvest and process food, there is a genuine risk of heat stroke, which can lead to loss of consciousness and can result in death if not detected at an early stage.”

The Society points out that each year, during heatwaves in the UK, hundreds of working age people die from heatstroke. BOHS is calling for farming organisations to do more to highlight the direct health risks associated with heat stress and the broader impacts of heat stress on safety, mental health, and long-term ill health.

This call comes as Westminster MPs have tabled an early day motion to limit the threshold for working temperature to 30 degrees.

“Livestock farmers are very familiar with the impact of heat on animal welfare and there is widespread information and focus on managing it," said BOHS CEO, Professor Kevin Bampton. "We would like to see farm workers treated with at least as much care and attention as farm animals.

“Of course, we are very concerned about the welfare of all workers across sectors such as baking, foundries, construction and hospitality where heat is a risk factor, but we are particularly concerned that there is very little clear messaging through the farming community about the steps that they should be taking to protect their workers, who are often temporary seasonal workers.”

The scientific charity for worker health protection has drawn attention to research it promoted by the European Heatshield project and Loughborough University that showed that 50% of agricultural workers started their shift already dehydrated. As well as the health effects, the impact of poor support for workers on productivity was demonstrated by the research, with a 16% reduction in productivity when temperatures reached over 29 degrees.

“The steps to prevent heat stress are simple. Make sure that there is easy and immediate access to clean, cold water; provide shade, at the very least in rest areas; ensure clothing is suitable; schedule tasks for cooler parts of the day; provide adequate breaks, ensure farm vehicle air conditioning systems are working, ensure all workers and supervisors are aware of the risks; discourage the drinking of caffeinated and, particularly, alcoholic drinks.”

Alongside ensuring sun protection against the risk of skin cancer, the Society believes that these simple steps, if widely promoted can save lives and have a positive impact on food production at a time of rising food prices.