Last year, we set out guidance for employers across Northern Ireland and Great Britain on managing extreme weather at work here. This insight provides a refresher on employers’ obligations and practical steps to keep your workforce safe and productive when the mercury rises.

Do employees in Northern Ireland have a legal right to down tools if it gets “too hot”?

Not necessarily, in Northern Ireland there is no absolute right to stop working simply because it is “too hot”, and the law does not set a specific upper limit at which employees can automatically down tools. Under health and safety law, employers must ensure indoor workplace temperatures are “reasonable” and that every outdoor workstation, so far as reasonably practicable, provides protection from adverse weather.

Employees also have the right not to be subjected to any detriment for leaving or refusing to return to a workplace in circumstances of danger they “reasonably believed to be serious and imminent”. This could potentially include, for example, a genuine risk of heat exhaustion, fainting or heat stroke.

Employers should consider what steps may be appropriate in their particular workplaces during periods of extreme heat, particularly as heatwave warnings become more frequent.. From an employee relations perspective, visible and proportionate steps can also help reassure staff and support attendance.

What should employers actually be doing?

General duty

Under the Health and Safety at Work (Northern Ireland) Order 1978, employers in Northern Ireland must provide employees with a safe place of work. This means taking all reasonably practicable steps to protect employees’ health, safety, and welfare, both in the workplace and wherever they are working, and includes protecting staff from the risks linked to extremes of heat.

In such conditions, employee welfare centres on ‘thermal comfort’ – how acceptable a person considers their current temperature. This is influenced by both workplace conditions (such as heat and humidity) and individual factors (such as clothing and level of exertion). The Health and Safety Executive NI (HSENI) suggests the following practical measures:

• adjust or provide air conditioning units
• increase the number of open windows
• provide staff with fans
• install blinds on windows to reduce heat gain
• provide cold drinking water
• insulate hot plants or pipework
• place workstations away from direct sunlight
• job rotation
• relax requirements on the wearing of a uniform

While none of these measures are specific legal requirements, failing to meet your health and safety obligations can lead to serious penalties. Directors can be held personally liable if they allowed, were involved in, or failed to prevent a breach, and employees who suffer harm may also bring personal injury claims.

Dress codes – time to loosen the collar?

There is no specific legal requirement to relax dress codes or uniform requirements during extreme heat. However, the HSE recognises clothing as a relevant factor in thermal comfort, and where a risk assessment identifies that compulsory workwear may contribute to heat stress, complying with your duty of care will likely include relaxing the dress code. In practice, many employers adopt a common-sense approach and permit lighter clothing during heatwaves, even where a formal dress code ordinarily applies. This would need to be balanced with any competing safety requirements, for example steel-capped boots or overalls/Hi-vis jackets. 

When reviewing dress codes, you should also be aware of the potential risks of indirectly discriminating against some employees. Dress code requirements that may disproportionately affect employees with particular protected characteristics, for example, those interacting with religious dress, would need careful consideration. We would advise taking a flexible approach, for example simply allowing or recommending relaxation of any dress codes, rather than enforcing changes, and seeking specific legal advice if you have any concerns.

Protecting employees at particular risk

Extreme temperatures do not affect everyone equally, and employers should pay particular attention to employees for whom heat presents additional risks. This includes pregnant employees, those with disabilities or health conditions (such as cardiovascular or respiratory issues, or conditions affecting thermoregulation), and those taking medication that affects heat tolerance.

The duty to make reasonable adjustments under the Disability Discrimination Act 1995 requires employers who know, or ought reasonably to know, of an employee’s disability and disadvantage to take proactive steps, particularly when extreme heat is forecast.

It is also worth remembering that menopause symptoms, including hot flushes, fatigue, and difficulty concentrating, can be made worse by already high temperatures. Employers should think proactively about how to support any affected employees, keeping thermal comfort in mind.

Handling complaints

Employers should take complaints about extreme heat seriously and address them appropriately. The potential consequences of failing to do so were illustrated in the English Tribunal case of Miss L Ayad v WL Retail Ltd, decided last year. In that case, a café worker raised concerns that the workplace was too cold (as low as 12°C), pointing to health and safety guidance recommending a minimum of 16°C. Although the case concerned cold rather than heat, the Tribunal accepted that raising these concerns could amount to protected disclosures about health and safety. The employee's dismissal was ultimately found to be automatically unfair on the basis of those disclosures, and she was awarded £22,000 in compensation.

This case serves as a clear reminder that employers who dismiss or ignore employees' complaints about unsafe working temperatures, whether too hot or too cold, risk not only regulatory scrutiny but also significant legal liability, making it essential to have robust procedures in place for logging, investigating, and acting on such concerns promptly.

Adapting to rising temperatures

The current legal framework in Northern Ireland remains largely flexible and risk‑based, and setting a legal maximum working temperature does not appear to be high on the government’s agenda. However, with extreme, record-breaking weather becoming the norm rather than a rare exception, employers should keep an eye to future potential obligations.

In June 2025, Unite published a report calling for increased protection for workers during extreme weather in Northern Ireland and called for the introduction of clearer regulatory and legislative protections for workers. Suggestions included maximum workplace temperatures and more specific duties on employers to manage heat at work. 

For now, the focus remains on taking sensible, practical steps to look after workers’ wellbeing and help them work safely through rising temperatures. Whilst we await further regulation in this area, employers could consider the following when tackling workplace issues during extreme weather:

• Develop and communicate watertight extreme weather policies (with clear alert-based responses established).
• Ensure risk assessments are up-to-date, documented, and consulted on with worker representatives (including for workers travelling to and from work during extreme weather and those working from home).
• Carry out vulnerability assessments to determine which workers are more exposed to extreme weather-related risks (and when, how, and why)
• Assess the potential impact on more vulnerable groups of workers, such as pregnant workers, older workers, and those with chronic health conditions or disabilities.
• Establish clear communication channels so that expectations during extreme weather can be delivered to employees promptly.
• Consider, and when necessary, prepare for the financial implications of paid climate leave.
• Consider whether PPE should be modified to adapt to extreme weather.
• Review and adapt workplace infrastructure and practices to comply with temperature and safety standards (for example, ensuring suitable air conditioning provisions are in place).
• Engage proactively with unions and regulatory bodies to ensure compliance and protect both staff and organisational reputation.