Climate as a Workplace Hazard: How HSE Leaders Must Rethink Risk in the Age of Extreme Weather

There is a dangerous assumption embedded in most corporate Health, Safety, and Environment (HSE) frameworks — the assumption that the climate is essentially a backdrop. Weather is something you plan around; you issue a heat advisory when it’s hot, you watch the forecast before an offshore operation, you add “flood” to your emergency checklist and call it climate-ready. This was the mindset until 2024, when the International Labour Organisation (ILO) called attention to the connection between climate change and occupational health and safety, framing it as the theme for the World Day for Safety and Health at Work: “The Impacts of Climate Change on Occupational Safety and Health.”

The world changed definitively in 2024. The World Meteorological Organization confirmed it as the hottest year in recorded human history, with the temperature 1.55°C above pre-industrial temperatures — and that record was set not in a particularly active El Niño year but as part of a straight-line trend that shows no sign of reversal. Daytime temperatures above 40°C are no longer anomalies confined to the Gulf or the Sahel. They are appearing across southern Europe, South Asia, and parts of West Africa with a regularity that is forcing a fundamental reconceptualisation of what we mean by a “normal” operating environment.

This is the challenge facing every HSE leader and ESG professional right now: climate-driven risks have migrated from the “long-term” column of the risk register to the “immediate” one. They are physical, they are measurable, and increasingly they are legally actionable. The organisations that fail to reclassify them will pay in injuries, in productivity losses, in litigation, and in reputational damage that no sustainability report can undo.

The Numbers Behind the Emergency

More than 2.4 billion workers are globally exposed to excessive heat each year. An estimated 18,970 fatalities and 22.85 million occupational injuries per year are linked to excessive heat. In 2024 alone, $320 billion was lost to natural disasters globally. And for every degree the ambient temperature climbs above 20°C, worker productivity drops by approximately 2–3%.

The extreme weather events make the news. What rarely makes the news is the slower, quieter toll that compounds in every workday between those headline disasters. Consider that 2–3% productivity reduction per degree above 20°C — a conclusion drawing on five decades of occupational health research, as synthesised in the joint WHO-WMO guidance published in 2025. For an outdoor construction crew in Lagos, Karachi, or Seville during a July heatwave, that is not an abstraction. It is concrete operational inefficiency that cascades through project timelines, labour costs, and quality control. Multiply that effect across an entire supply chain and the financial exposure becomes material in ways that CFOs and investors are only beginning to price.

But productivity loss is only the most easily quantified harm. The WHO-WMO report also detailed the health consequences of chronic heat exposure: heat stroke, kidney dysfunction, cardiovascular disease, and neurological disorders — conditions that don’t announce themselves in a single dramatic incident but develop silently over seasons of exposure. A construction worker who spent three summers working in dangerously high temperatures and develops chronic kidney disease at 48 is a climate-related occupational casualty, even if no one will ever classify it that way. This attribution gap — the difficulty of connecting individual health outcomes to climate conditions — is one of the most consequential blind spots in current HSE frameworks.

The other dimension that gets routinely underweighted is the cascading nature of climate risk. When Hurricane Helene struck the southeastern United States in October 2024, it didn’t just damage local infrastructure — it disrupted facilities responsible for a significant share of global high-purity quartz production, sending shockwaves through semiconductor supply chains worldwide. A drought in southern Brazil’s Rio Grande do Sul state in 2024 affected a region accounting for 12.7% of the country’s agricultural output. These are not exceptions. They are the new logic of physical risk: geographically concentrated, systemically amplified, and far more interconnected than traditional risk registers assume.

The Strategic Failure of the “Emergency Preparedness Checklist” Approach

Most organisations currently address climate-related workplace risks through one of two approaches — both of which are inadequate for the environment we are now operating in.

The first is the reactive approach: wait for an extreme weather event, activate emergency protocols, recover, and return to normal operations. This model was designed for discrete, infrequent disruptions. It has no architecture for managing risks that are now essentially continuous, where “normal” operating conditions in many regions already exceed historical safety thresholds for significant portions of the year.

The second is the compliance approach: meet the minimum legal standard for temperature, ventilation, and emergency preparedness, and treat that as the finish line. This approach mistakes the absence of prosecution for the presence of safety. In most jurisdictions, those minimum standards were written in a different climatic era and have not been updated to reflect the current thermal baseline. An employer who complies with a 1980s-era heat exposure standard is not protecting their workers from a 2026 heatwave. They are merely insulating themselves from yesterday’s liability while accruing tomorrow’s.

Four Dimensions of Climate-as-Hazard That HSE Leaders Must Own

On thermal stress: The WHO-WMO 2025 report explicitly noted that workers in both outdoor and indoor environments are affected. As urban heat island effects intensify and air conditioning infrastructure fails to scale in many parts of the Global South, indoor workplaces that were once considered thermally safe are becoming hazardous during extended heatwaves. A robust heat risk framework must account for individual vulnerability — including age, chronic conditions, physical fitness, and medications — not just aggregate ambient conditions.

On air quality: A logistics company whose drivers are on the road during a wildfire smoke event, a construction company whose crews are working in ozone-elevated conditions during a heatwave, a utility company whose field engineers are deployed after a flood into an environment with elevated chemical contamination — all face climate-amplified occupational exposures that their standard risk assessments were not designed to evaluate.

On psychosocial risk: Workers in climate-exposed sectors are not only physically stressed by climate conditions. They are increasingly experiencing what researchers have termed “eco-anxiety” and climate grief: the sustained psychological distress arising from the awareness of accelerating environmental degradation, the experience of repeated climate-related disruptions, and uncertainty about the future viability of their work and communities.

The ESG-HSE Integration Gap

There is a strategic paradox that should trouble every ESG professional: most large organisations are simultaneously producing increasingly sophisticated ESG disclosures about climate risk and running HSE functions that have not yet integrated climate as a core hazard category. These two functions report to different parts of the organisation, use different frameworks, speak different languages, and rarely share data.

The result is a systematic gap between what companies say about climate risk in their sustainability reports and what they actually do about it in their operations. As CSRD, TCFD, and emerging national reporting requirements demand greater specificity about how physical climate risks affect the workforce, organisations that cannot demonstrate operational integration will face scrutiny from regulators, investors, and plaintiffs alike.

The World Economic Forum’s Global Risks Report 2025 ranked extreme weather events as the second-highest global risk in the two-year outlook and the top risk in the ten-year outlook. Climate attribution science — the field that connects specific climate events to anthropogenic warming — has advanced rapidly. Researchers can now quantify with increasing precision how much more likely a particular heatwave was because of climate change. This science is finding its way into courtrooms. An employer whose worker suffers heat stroke in conditions that climate science characterises as significantly intensified by climate change, and who had not updated their heat risk protocols beyond decades-old standards, faces a legal exposure that their team should be urgently assessing.

A Structured Path Forward

The tools, frameworks, and evidence base for managing climate as a workplace hazard are more developed than most HSE functions have yet utilised. The challenge is less about knowledge than about integration and will.

The Opportunity Side

Organisations that move early and deliberately will find genuine advantages. Insurers and lenders are already pricing physical climate risk into their books, and demonstrated robust risk management is opening access to preferential terms. Many interventions that reduce climate-related health risk — better scheduling, improved shelter, acclimatisation protocols, real-time environmental monitoring — also reduce inefficiency, absenteeism, and turnover.

• In a globally uneven regulatory environment, adopting higher standards than local jurisdictions require insulates organisations from disruption when standards eventually catch up.
• Genuine operational integration of climate risk management is a form of ESG credibility that no marketing budget can replicate — particularly as scrutiny of corporate sustainability claims intensifies.
• Insurers and lenders are already pricing physical climate risk into their books — demonstrated robust risk management opens access to preferential financing terms.
• In physically demanding sectors, workers are increasingly choosing employers they trust to keep them safe — climate resilience is becoming a talent retention differentiator.