Heat stress at work—a political emergency

Climate change is creating new risks, requiring a minimum protective threshold for all workers in Europe. 

In 2022, 61,000 deaths in the European Union were attributed to summer heat. Likely  an underestimate, this is only one of many indicators of the growing and unavoidable challenge posed by the impacts of climate change on public health and the world of work. The European Environment Agency forecasts a steady rise in average temperatures, as well as increasingly frequent and intense heatwaves, which have been described as ‘silent, invisible killers of silent, invisible people’.

According to Eurofound, 23 per cent of workers in the EU are exposed to high temperatures for at least a quarter of their working hours; that climbs to 36 per cent in agriculture and industry and to 38 per cent in construction. These sectors are known for precarious working conditions and recruitment of more vulnerable (temporary and migrant) workers.

Workers are also at risk from other aspects of climate change and ever-more-extreme weather conditions. The European Agency for Safety and Health at Work (EU-OSHA) warns of extensive repercussions, particularly in emergency services, water supply, energy, transport and construction.

High-risk situations

Those working outside, such as in construction, agriculture or maintenance of public spaces, are most exposed to extreme climate conditions (including ultra-violet radiation). Those working in the emergency, rescue and cleaning/maintenance services often find themselves meanwhile in high-risk situations because of floods, landslides, storms, droughts and wildfires—yet climate emergencies will only increase the need for such assistance from often cash-strapped services.

Indoor workers whose jobs require physical effort, as in warehouses or on production lines, will also be affected by rising temperatures and humidity. The impact on health can be immediate, ranging from cramp and oedema (local build-up of body fluids) to loss of consciousness and even death. Studies also however point to the long-term risk of exposure to intense heat, with the potential for heart, kidney or liver damage, as well as chronic tiredness, sleep disturbance and temporary infertility . 

In France, the National Scientific Research Institute (INRS) and the Agency for Food, Environmental and Occupational Health and Safety (ANSES) have registered the extra psychosocial risks associated with global heating. Heat is tiring and adds cognitive strain, which can spark irritability or even violence, risking tensions and conflict among workers and with non-colleagues. Cognitive fatigue also increases the risk of accidents at work, especially because it reduces concentration and can lead to fuzzy decision-making, posing extreme danger when driving or operating machinery. 

As EU-OSHA has stressed in its guidance, heat stress also has indirect effects on workers, exacerbating risks stemming from air pollution, self-heating materials, biological agents and chemical substances. Heat can also affect the application of certain health-and-safety measures, notably the wearing of personal protective equipment—potentially even turning it into a risk itself. 

Preventive measures

Incorporating climate hazards into occupational risk assessments is emerging as a key issue for workers’ safety in Europe. The imperative of sector-appropriate preventive measures, acknowledging that climate impacts depend on the type of work, underlines the importance of social-partner involvement. Where heat-related risks are concerned, EU-OSHA’s recent guide shows it is perfectly possible within an organisation to implement a system of preventive measures. 

The principles in the 1989 framework directive (89/391/EEC) on health and safety at work can be applied to heat stress. These include the employer obligation to evaluate all workplace risks and to adopt preventive measures—first collective, then individual—following an information-and-consultation process with workers and/or their representatives.

Employers should evaluate the risks created by climate change, taking various factors into account, including a worker’s protective clothing, age and health. For heat exposure, biological differences should also be considered, given that some studies note women may be less heat-tolerant than men. 

According to EU-OSHA, application of the existing obligation to develop a comprehensive, consistent policy to prevent heat stress should lead to implementation of action plans, an early-warning system and safe working practices. The risk assessment should be succeeded by a hierarchy of controls, perhaps including emergency procedures and a ‘buddy’ system. Working in isolation poses a considerable risk, given that it is very difficult for someone to assess their own heat tolerance—if an incident occurs, assistance from a third party is vital for administering first aid and raising the alarm.  

The information workers receive on the dangers of heat stress should include descriptions to help them recognise the symptoms of heat-related injuries and illnesses, measures to reduce the risk, acclimatisation and procedures to follow in the event of heat-related illness. In the absence of specific legislation on heat stress, however, there is no guarantee employers will abide by these recommendations. 

Legislative void 

The measures EU-OSHA urges require the option for workers of adjusting their time schedules and a needs-based reduction in labour intensity, regardless of economic pressures, which may require a larger workforce. Especially in sectors with a vulnerable workforce, power differentials will not make it easy for workers to behave in a way that prioritises their health. In France, the sociologist Annie Thébaud-Mony, a specialist in occupational health, is thus advocating express reference to heat-related risks in the Labour Code—so far without success—including changes to working schedules during periods of high temperatures.

In Greece, the guards working in the Acropolis have secured an adjustment to their schedules that avoids afternoons during heatwaves. This flexibility is vital to protect workers’ health but should apply across the board so that all sectors can benefit. 

Legislation varies considerably from one country to another. In Spain, measures based on weather alerts are in place to prohibit outdoor working in periods of extreme heat. In Portugal, the temperature of a workplace must be between 18 and 22 Celsius and there must be a system to manage humidity. In the Belgian ‘law on thermal environmental factors’, targeted at heat and cold, action is mandatory when the occupational-exposure temperature limit is exceeded (according to the wet-bulb globe temperature index, which takes in humidity and wind). in Germany, despite recommendations to this effect, there is no occupational exposure limit on heat stress. Legislation needs to be harmonised to provide a minimum protective threshold for all workers in Europe. 

In this ‘legislative void’, national case law has begun to provide some ad hoc protection. In 2015 in France, roofers exercised their ‘right to withdraw’ in the event of serious, imminent danger and stopped working during a heatwave. In Italy that year, a ruling found that where working conditions were unsafe or temperatures were ‘prohibitive’ workers had the right to stop working with no loss of earnings or risk of dismissal.

Restoring autonomy

Today, we face a political emergency. Outdoor workers are excluded from the protective scope of some European directives. The sectors most affected are also those where precariousness is greatest. We must resist the fatalistic narrative that nothing can be done—that it is ‘all part of the job’.

Ensuring workers are genuinely protected means revising economic needs and objectives downwards. We must restore human beings to the heart of how work is organised. Workplaces must see an increase in available resources or a reduction in the pressures of work.

All the indicators point in one direction: the best preventive measures require workers to be able to regulate their own hours and tasks, so they can alternate rest periods with work. This means restoring some autonomy to workers but that will only be genuine if it is exercised in an environment where economic pressures and power are constrained.

It would be naïve to assume workers will prioritise their own health and that of their colleagues if doing so would put their jobs at risk. We need Europe-wide measures that will enable workers to be heard, empowered, recognised and protected.

Explore the topic ‘Workers and the climate challenge’ in the latest HesaMag, the health-and-safety magazine with a European perspective from the European Trade Union Institute