Total Rewards Asia Summit 2024 Singapore
Your guide to ensuring workplace safety & health amidst climate change: Excessive heat, extreme weather, and more

Your guide to ensuring workplace safety & health amidst climate change: Excessive heat, extreme weather, and more

As global occupational safety & health protections struggle to keep up with the evolving risks from climate change, the impact is felt in worker mortality and morbidity.

From excessive heat to extreme weather events, the impact of climate change is being felt all around the world. In fact, the earth’s average surface temperature in 2023 was the warmest on record, with July 2023 being the hottest month ever recorded. 

Naturally, the effects of such a phenomenon extend all the way to the safety and health of workers in all parts of the world.

According to the International Labour Organisation (ILO), workers – especially those working outdoors – are among those most exposed to climate change hazards. They are often the first to be exposed to the effects of climate change, often for longer periods and at greater intensities than the general population. 
Despite dangerous conditions, they frequently still have no choice but to continue working. 

As global occupational safety and health (OSH) protections struggle to keep up with the evolving risks from climate change, the impact is felt in worker mortality and morbidity.

The Ensuring safety and health at work in a changing climate report emphasises the importance of collaborative efforts to develop and implement effective mitigation and adaptation measures to protect workers across the globe. The report aims to bring attention to the following key issues:

  • Excessive heat
  • Ultraviolet (UV) radiation
  • Extreme weather events
  • Workplace air pollution
  • Vector-borne diseases
  • Agrochemicals

The report acknowledges that whilst some of these risks may be considered as primary consequences of climate change (e.g., excessive heat), others can be regarded as secondary impacts (e.g., vector-borne diseases and wildfires). These topics were selected due to the severity and magnitude of their effects on worker populations.

For each of these risks, the report aims to provide evidence regarding worker exposures and the main safety & health effects that result, while also detailing existing responses to the risk.

Excessive heat

Workers at high-risk: Workers in agriculture, environmental goods and services (natural resource management), construction, refuse collection, emergency repair work, transport, tourism, and sports.

Primary health impact: Heat stress, heatstroke, heat exhaustion, rhabdomyolysis, heat syncope, heat cramps, heat rash, cardiovascular disease, acute kidney injury, chronic kidney disease, physical injury.

Global burden of occupational exposures: At least 2.41bn workers exposed to excessive heat annually. 

As the report clarifies, workplace heat stress refers to the excess heat load a worker can be exposed to due to different contributing factors, acting alone or in combination. These include environmental conditions, such as air temperature and humidity, and heat sources from industrial settings, such as heat-emitting sources and machinery. 

Factors which increase heat-stress risks:

  1. Environmental heat exposures - e.g., increased air temperature/humidity, limited air flow, radiant heat sources
  2. Metabolic heat production - e.g., performing physically demanding tasks
  3. Thermal insulation - e.g., work clothing and/or PPE

In response, some countries are including heat-related risks as a key priority in national OSH policies and strategies. For example, legislation in Thailand has instructed that work must be stopped when the wet bulb globe temperature (WBGT) rises above 34°C for low intensity work, 32°C for moderate intensity work, and 30°C for very high intensity work (Occupational Standard 2016).

In Singapore, the temperature in any working chamber, man-lock, or medical lock in a worksite shall not exceed 29°C (Workplace Safety and Health (Construction) Regulations 2007).

The ILO Code of Practice on Ambient Factors in the Workplace: Chapter 8 Heat and Cold has outlined the following:

Where assessment shows that the workers may be at risk from heat stress, employers should, if practicable, eliminate the need for work in hot conditions or, if elimination is not practicable, take measures to reduce the thermal load from the environment.

Where the assessment shows that health or discomfort conditions arise from increased air temperature, the employer should implement means to reduce air temperature, such as a ventilation system. The design should take into account seasonal and sudden temperature changes in make-up air brought from outside. If the air temperature is below about 36°C, increasing air movement (for example by fans) will cool the workers; above that temperature it will heat them further.

Ultraviolet (UV) radiation 

Workers at high-risk: Outdoor workers, including in construction and agriculture, lifeguards, power utility workers, gardeners, postal workers and dock workers.

Primary health impact: Sunburn, skin blistering, acute eye damage, weakened immune systems, pterygium, cataracts, skin cancers.

Global burden of occupational exposures: 1.6bn workers exposed annually to solar UV radiations.

According to the report, solar UV radiation is a form of non-ionizing radiation. Short-term injuries from UV exposure include sunburn, skin blistering and eye damage, and are normally temporary. However long-term effects can be serious. These include cataracts, macular degeneration, pterygium, weakened immune systems and skin cancers, such as melanoma.

Existing policies include the Philippines' Occupational Safety and Health Standards (art 1076.05 (2)), which contain provisions to protect workers against radiation in general. More specifically, the Labour Advisory No. 03 (2016) states that PPE for the head, body and extremities must be provided, including hats, goggles or UV protective eyewear and comfortable, light long-sleeve t-shirts, to mitigate the effects of extreme heat at work.

The ILO Code of Practice on Ambient Factors in the Workplace: Chapter 8 Optical radiation has outlined the following:

7.3.7. Employers should, where practicable, in the case of outdoor work:

    • minimise exposure of workers to the sun by organising the work so that it can be carried out in the shade;
    • protect workers by appropriate clothing and personal protection, such as sunscreen ointment or lotions and eye protection, when necessary.

    7.5.1. Employers should inform workers likely to be exposed to significant levels of optical radiation and/or involved in work with lasers:

    • about the hazards to health of optical radiation and the sources and activities that may pose a risk of exposure, especially about the need for protection against the effects of the sun;
    • of the importance in outdoor work of using any available shade and personal protection, where indicated, including protective clothing and sunscreen ointments and lotions; and
    • that some perfumes and medicines can cause sensitisation on exposure to UV radiation and that they may need to consult their physician.

    Extreme weather events

    Workers at high-risk: Medical personnel, firefighters, other emergency workers, construction workers involved in clean-up, agricultural and fishing workers.

    Primary health impact: Various.

    Global burden of occupational exposures: Limited data.

    The ILO Guidance to protect workers in extreme weather events has outlined:

    According to Article 9, in respect of each major hazard installation employers shall establish and maintain a documented system of major hazard control which includes provision for: […]

    (d) emergency plans and procedures, including:

    • the preparation of effective site emergency plans and procedures, including emergency medical procedures, to be applied in case of major accidents or threat thereof, with periodic testing and evaluation of their effectiveness and revision as necessary;
    • the provision of information on potential accidents and site emergency plans to authorities and bodies responsible for the preparation of emergency plans and procedures for the protection of the public and the environment outside the site of the installation;
    • any necessary consultation with such authorities and bodies.

    Workplace air pollution

    Workers at high-risk: All workers, particularly outdoor workers, transport workers and firefighters.

    Primary health impact: Cancer (lung),respiratory disease, cardiovascular disease.

    Global burden of occupational exposures: Increased risk of exposure to air pollution for the 1.6bn outdoor workers.

    As the changing climates modify weather patterns, the levels and location of pollutants have also been impacted, such as ground-level ozone, fine and coarse particulate matter, nitrogen dioxide and sulphur dioxide.

    The Working Environment (Air Pollution, Noise and Vibration) Convention, 1977 (No. 148),Working Environment (Air Pollution, Noise and Vibration) Convention, 1977 (No. 148) has outlined:

    Article 9

    As far as possible, the working environment shall be kept free from any hazard due to air pollution, noise or vibration--

    • (a) by technical measures applied to new plant or processes in design or installation, or added to existing plant or processes; or, where this is not possible,
    • (b) by supplementary organisational measures.

    Vector-borne diseases

    Workers at high-risk: Outdoor workers including farmers, foresters, landscapers, groundskeepers, gardeners, painters, roofers, pavers, construction workers, firefighters, among others.

    Primary health impact: Diseases such as malaria, Lyme disease, dengue, schistosomiasis, leishmaniasis, Chagas disease and African trypanosomiasis, among others.

    Global burden of occupational exposures: Limited data.

    The report defines vector-borne diseases as illnesses caused by parasites, viruses and bacteria that are transmitted by vectors. A large proportion of burden of such diseases lies in tropical and subtropical areas. Some examples of vectors and the diseases they cause are as follows:

    Studies have shown a link between climate change and an increased risk of vector-borne diseases in workers — as climate change is expected to alter the seasonality, distribution, and prevalence of existing vector-borne diseases, such alterations can impact disease incidence through effects on vector population sizes, survival rates, and reproduction.

    Citing the World Health Organisation, the ILO points out that the need for protective measures at the workplace level is most acute for dengue fever, chikungunya, leishmaniasis, and Chagas disease, as there are no obvious methods of treatment nor effective vaccines.


    Workers at high-risk: Workers in agriculture, plantations, chemical industries, forestry, pesticide sales, green space, vector control.

    Primary health impact: Poisoning, cancer, neurotoxicity, endocrine disruption, reproductive disorders, cardiovascular disease, COPD, immune suppression.

    Global burden of occupational exposures: Increased risk of exposure to agrochemicals for a significant number of the 873mn workers employed in agriculture.

    With approximately 873mn workers employed in agriculture worldwide, the workers are particularly at risk for exposure to pesticides and other agrochemicals, such as fertilisers. 

    The changing climate also impacts fertilisers. 

    Exposure to workplace is frequently sustained over years of work and can lead to both acute and chronic health effects. Occupational exposure occurs during handling, dilution, mixing, application, and disposal of pesticides, as well as during cleaning of containers and handling of crops.

    The first step to ensure the safety & health of workers who may be exposed to pesticides is to conduct a thorough risk assessment should be carried out at the workplace level to identify hazards, assess risks, and implement appropriate control measures. Start by identifying pesticides present in the workplace and the workers exposed to them. Hazards should be identified and the risks assessed before a new process is started for work activities, or involving the use of pesticides or if new pesticides are introduced.

    Following the risk assessment, there is a hierarchy of controls should be applied in order to eliminate or minimise the risks from pesticide exposures. The most effective way to prevent exposure is through elimination or substitution with viable, less toxic alternatives. On the lower end of the spectrum, PPE should only be relied upon where it is not possible or practicable to control exposure by one or more of the other control measures.

    Lead image and infographics / Ensuring safety and health at work in a changing climate

    Follow us on Telegram and on Instagram @humanresourcesonline for all the latest HR and manpower news from around the region!

    Free newsletter

    Get the daily lowdown on Asia's top Human Resources stories.

    We break down the big and messy topics of the day so you're updated on the most important developments in Asia's Human Resources development – for free.

    subscribe now open in new window