It’s increasingly important for those working in health and safety to take the effects of climate change into consideration, as Bridget Leathley explains.

It should be obvious why we should care about the way we treat the place we live and do our best to cause as little harm as possible. But as individuals we can feel that our personal efforts to reduce, reuse and recycle have a negligible impact on the climate. In January 2025, climate scientists confirmed that in 2024 we breached the precious 1.5°C target – that is, Earth’s average temperature climbed to more than 1.5°C above pre-industrial levels.

But if you have responsibilities for the safety, health or welfare of workers there are things you can do that will make an impact – not to stop climate change, but to manage its harmful effects on your workforce by including climate hazards in your risk assessments.

The weather

The weather is probably the first hazard we think of when considering climate change. The impact of storms and floods on outdoor work is obvious, and those driving for work might feel pressurised to make journeys in heavy rain or storms, when conditions on the road are hazardous.

High temperatures can make concentration on a complex task more difficult, and physical tasks more exhausting. One study shows that on days with temperatures above 32°C, workers have at least a six per cent higher chance of injuries than on cooler days, and temperatures above 38°C increase the risk by up to 15 per cent. The International Labour Organization (ILO) estimates that worldwide, 22.85 million occupational injuries each year have excessive heat as a cause.

Without additional controls, climate change means outdoor workers will be exposed to more UV radiation – a recognised cause of cancer. The ILO predicts an increase in skin cancer of 11 per cent by 2050, with workers in traditionally cold climates also being affected.

Indoor workers are not immune from the impact of weather. Will your existing heating and ventilation systems be able to manage the extremes of temperature predicted with climate change?

Changing patterns of rainfall and flooding can affect the foundations of buildings and external walls, and storms when trees are in full leaf will have more impact than traditional winter storms, potentially leaving trees dangerously unstable.

Don’t forget the mundane – do you have the resources needed to manage icy pavements outside your building if it becomes more difficult to predict when cold weather snaps will occur, and if they happen more often? If people become cold while working, they are more error-prone and more susceptible to soft tissue damage, chilblains, vibration injuries and in extreme cases, frostbite.

Air pollution

If you use labelled substances that are known to be respiratory hazards, you already have controls in place – substitute or reduce, isolate, ventilate, use PPE and carry out health surveillance. But what about the substances in the air that aren’t labelled?

Multiple climate factors conspire to make air pollution worse. As weather patterns change there is pressure on farmers to use artificial fertilizers and pesticides to maintain yields from the land. These can add to air pollution during spraying, when dust that the chemicals adhere to blows into the air, and when farmers burn pesticide-treated crop residues. Wildfires, such as those seen in London in 2022, release particulate matter into the atmosphere.

Higher temperatures increase ground-level ozone and accelerate the formation of some air pollutants. Deforestation has reduced the ability of trees to filter pollutants out of the air, making the problem worse.

The ILO estimated in 2021 that across the world, there were 860,000 deaths because of exposure to air pollution amongst outdoor workers. Although a high proportion of these deaths are in lower and middle-income countries, a study by Kings College London in 2020 found that outdoor workers in London were exposed to 15 per cent more pollution than the average Londoner, with exposure well above WHO recommended limits.

But climate change is also increasing indoor air pollution. As well as the outdoor pollutants that enter a building, increased temperatures make VOCs (volatile organic compounds) present in our workplaces more volatile. VOCs cause symptoms from irritation of the eyes, nose and throat through to severe respiratory issues, and can be carcinogenic.

Biological hazards

Milder winters and warmer temperatures could change the wildlife that thrives on the British Isles, including rodent and insect pests along with the diseases they carry. Using pesticides and poisons to manage the problem will add to the hazardous substances already in the environment.

In 2024 the medical journal, the Lancet, published a paper explaining how climate change is leading to an increase in fungal diseases, as fungi are benefiting from warmer temperatures, and the increasing vulnerability of humans.

Variations in indoor temperature and humidity increases mould growth on building surfaces. Mould can trigger allergic reactions, exacerbate asthma, and in severe cases result in death from infections or toxins.

Flooding can bring people into closer contact with traditional biological hazards – such as when sewers overflow during floods.

Action

While we can still take measures to reduce the rate at which climate change impacts us, it’s too late to stop it. These five steps can help mitigate the impacts:

1. Identify who will be most affected by climate change. If people are doing strenuous work outdoors, they will breathe more heavily and inhale pollutants more quickly. People with pre-existing respiratory conditions such as asthma will be at greater risk. Those working with animals, or with human waste, will be more exposed to pests and disease, and outdoor workers have less protection from the extremes of weather.
    
2. Monitor. Measure working temperatures, air quality and exposure to sunshine. Building management information systems might be able to provide information for inside, or for smaller premises you can buy portable digital devices which measure and record temperature and humidity, as well as particulates, CO₂, formaldehyde (which contributes to ozone) and VOCs in the air. For outdoor workers, mobile monitoring devices allow you to track individuals’ exposure through the day. Make sure your inspection regime for walls, buildings and trees takes account of the impacts of heavy rain, unseasonal windstorms and droughts.
    
3. Reduce the hazard at source. Do you need to change your pest control regime? Can machinery take over strenuous tasks, with workers controlling equipment remotely? Can you improve the air quality by reducing VOCs and improving ventilation? Can you change how water flows on your premises, channelling floods away from vulnerable structures?
    
4. Limit exposure to hazards. Plan jobs to avoid working at the hottest or coldest times. Make sure welfare requirements, such as water, shelter and appropriate clothing are provided, and give workers flexibility about when to take breaks.
    
5. Health surveillance. Provide workers with advice about relevant symptoms to report. As well as physical symptoms such as skin rashes and respiratory conditions, ask about psychological symptoms, such as fatigue, difficulty in concentrating and minor errors. Use the feedback to determine what additional controls are needed.
    

Green hazards

As we rush to find green solutions to climate change, we must stop to consider any unintended consequences. Reducing diesel emissions with electric vehicles changes the way we manage fire risk; asking employees to use public transport instead of driving could increase lone-worker or manual handling hazards for some roles and improved insulation to save energy can reduce ventilation needed to prevent indoor air pollution building up.

Mental health hazards

Stress, anxiety and depression have overtaken musculoskeletal injuries as the leading reason for work absences. Employers must identify and reduce work-related causes of stress, but it’s in the interests of businesses to help people cope with external stressors like the economy and global conflicts. Eco-anxiety has been defined as “a chronic fear of environmental doom”, so when raising workers’ awareness of the changes needed to respond to climate change, we must be careful not to feed this fear.

Conclusion

If protecting lives and health isn’t enough of an argument for those holding the resources you need to manage the impacts of climate change, talk about productivity losses. The ILO estimates that by 2030, 2.2 per cent of working hours will be lost to high temperatures. That’s like losing the work of one worker from every 45 people you employ. That seems like a good reason to start including climate hazards in your risk assessments.
 

With a first degree in computer science and psychology, Bridget Leathley started her working life in human factors, initially in IT and later in high-hazard industries. After completing an MSc in Occupational Health and Safety Management, she moved full-time into occupational health and safety consultancy, training and writing.