The Heat is On: Protecting workers from extreme heat - A roadmap for Climate Resilient Supply Chains

By Tek Singh Bhat and Ana Maria Soto Bernal

Keywords: extreme heat, migrant workers, supply chains, worker well-being, labor rights, heat stress, climate resilience, ethical sourcing

When the Temperature Rises, So Does the Risk

According to NASA, 2024 was the warmest year on record since 1880 - and here in Bangkok it feels like it keeps getting hotter. In Thailand and Malaysia, last year between March and May, temperatures reached up to 42.3°C in some provinces in Thailand and 37°C in some areas in  Malaysia, often with suffocating humidity. 

With up to 10.5 million migrant workers powering the economies of Thailand and Malaysia, these workers form the backbone of global supply chains in manufacturing, agriculture, and construction. To understand how rising temperatures affect this critical workforce, Issara conducted an assessment of 250 workers from Bangladesh, Cambodia, Myanmar, and Nepal. 

The aim was to:

• Assess how extreme heat impacts workers’ health, productivity, and well-being.

• Understand workers’ awareness of heat prevention practices like hydration, shade, and rest breaks.

• Identify gaps between awareness and actual workplace safety conditions.

• Strengthen access to information and promote safer, climate-resilient workplaces.

  
  

The findings provide a clear picture of the serious impact of climate change on workers’ health. 87% of worker respondents said they experienced physical problems when it got too hot, sweating excessively, feeling dizzy, feeling tired, or having headaches. About half said they had to stop or rest because the heat became unbearable. 

The impact from extreme heat didn’t stop when work ended. 82% of workers stated that they could not sleep properly at night due to the high temperatures, leaving them feeling drained and restless. And this constant fatigue was more than just discomfort; it accumulated over time. Nine in ten workers said they felt more exhausted at work because they hadn’t slept well. For some workers, the heat followed them everywhere, from the factory floor to their dorm rooms, turning daily life into a cycle of fatigue and struggle.

Struggling to Stay Cool: Unsafe Conditions and Lack of Protection for Workers

The findings underscore how workplace readiness for extreme heat is falling short in many areas. Only 38% of workers reported that their workspaces were properly shaded or ventilated. Alarmingly, 60% said they spend most of their day working under direct sunlight or inside hot, enclosed workshops. In Thailand, migrant workers from Myanmar and Cambodia reported often lacking proper rest areas, fans, and even access to drinking water. Although Nepali and Bangladeshi workers in Malaysia reported slightly better conditions, heat exposure remains a widespread issue across the board.

Additionally, inappropriate clothing further increases risks for workers. Only 60% said their clothing or gear was suitable for hot weather, while 23% reported they had no proper clothing at all, for example not having breathable or lightweight clothing. Over 80% of workers - especially workers in Thailand from Myanmar and Cambodia - reported that such clothing would help.

While extreme heat risks to workers can be missed by companies and audits, they can be easily and safely reported by workers through anonymized and safeguarded worker voice channels. Employers can then take action. For instance, during the summer months of 2025, Issara regularly received calls and messages from workers reporting overheated workplaces, lack of drinking water, no proper rest areas, or absence of cooling equipment like fans or air coolers. By collaborating with suppliers / employers, these issues were able to be raised and resolved quickly - improving outcomes for both workers and the businesses. 

But what if workers have limited ways to raise their voices? This is a critical issue for responsible sourcing and ensuring ethical workplace conditions. It requires urgent attention. Action can be taken from all actors in the supply chain, starting with simply ensuring that there are safe channels available for workers to report extreme heat conditions and impacts, and employers communicating their openness to hear from workers about it. This will go a long way to guiding preventive actions to providing safe and healthy working conditions as temperatures rise.

Why should companies take action now?

It has been well documented that high temperatures in the workplace can impact the health and productivity of workers and the company’s bottom line. Studies on the direct impact of extreme heat risk on global supply chains also show a direct link between global heat stress and labor productivity loss, including indirect losses due to economic disruptions cascading through supply chains. The ILO projects that 2.2% of total working hours worldwide will be lost due to high temperatures by 2030. And Southeast Asia is projected to be the region most impacted.  We are already seeing these impacts. From Issara’s assessment of the 250 workers, 48% reported that heat forced them to stop working and rest. And as temperature continues to rise year by year, action to mitigate these risks needs to happen now.

From Response to Prevention: recommendations for action  

These findings are not only data and statistics, they are a wakeup call. Extreme heat isn't just an environmental crisis — it’s a labor rights crisis. It is destabilizing global supply chains and the products we rely on. 

If almost half the workers in this assessment alone reported stopping work due to extreme heat and 80% are distressed by sleep loss because of heat, then the question for governments and businesses is very clear:  “Are adequate steps being taken to protect workers and strong enough signals and support provided to business to prioritize extreme heat risks and to build more resilient supply chains?”

We aim to amplify the voices of workers and help build safer supply chains in an overheating world. Worker feedback makes one thing undeniable: as temperatures rise, workers are suffering in silence. It is time to turn that silence into action.

Here are some recommendations on what can be done to prepare for this summer:

Civil Society Organizations can also play a key role in raising awareness and providing support to prevent workers from facing health issues caused by extremely high temperatures.  Example activities at Issara include: educating and empowering workers via social media, Facebook live streaming information sessions, and Golden Dreams app; sharing awareness posts and resources provided by fellow non-profit organizations; engaging businesses and providing safe channels for workers to report extreme heat conditions; providing psycho-social counselling; and empowering workers to recognize the early signs of heat stress and dehydration and encouraging hydration, rest, and self-care.  

Key Take Aways 

• Heat is a Labor and Economic Issue: When 87% of workers report physical heat-related problems and 48% are forced to stop work or rest, the health of workers and the resilience of global supply chains are directly impacted. 

• The Safety Gap is Critical: Workplace readiness is alarmingly low, with 60% of respondents exposed to direct heat for most of the day, and only 38% of workspaces reported to provide proper shade or ventilation.

• Awareness and Training is Urgently Needed: While nearly all workers (98%) know that water and shade prevent heat stress, less than half (45.2%) are aware of early heat illness symptoms, and only 28.8% have received formal orientation or training on the risks.

• Go Beyond the Workplace: The impact extends beyond the shift and worksite, with 82% of workers reporting that extreme heat affected their sleep, leading to greater exhaustion and difficulty at work.

  
  

Our final call to action: The Pivot to Prevention

All actors in global supply chains can and should take action now - moving from awareness to managing heat risks to preventing it. 

For Global Brands and Retailers: 

• Integrate heat protection as a core element of your ethical sourcing policies and code of conduct 

• Partner with your suppliers and support them to make necessary investments in infrastructure such as cooling areas and climate-safe gear.

• Ensure there are safe channels for workers to report extreme heat conditions and risks 

  
  

For Suppliers/employers: 

Enhance workers well-being by implementing the full suite of protections: 

• Conduct thorough risk assessments and provide channels to hear from workers 

• Develop Occupational Heat Action Plans including formal triggers for work-rest cycles based on Wet Bulb Globe Temperature (WBGT) that takes into account temperature, humidity, wind speed, and sunlight.

• Provide accessible cooling areas and rest time, 

• Ensure suitable clothing and safe living spaces, 

• Ensure heat protection and communications are considered at every stage - during the recruitment process, at the workplace, during transportation, and at housing / dormitories. 

  
  

And most critically, for everyone: We cannot solve what we cannot see. Strengthen worker voice channels to monitor concerns in real-time and commit to taking immediate, life-saving action based on that feedback.

Ethical sourcing is not just about fair pay or decent housing. It is also about protecting workers from a changing, warming world. 

Let’s work together - companies, suppliers, workers, and civil society - to build supply chains that are safe, fair, and ready for the future. Because no one should have to risk their health just to do their job.