UNDERSTANDING AND PREVENTING HEATSTROKE AT SEA

Published: 15 May 2025

For seafarers, exposure to extreme temperatures is often part of the job. Whether working on deck in humid and/or sunny conditions, in a hot engine room, or in an enclosed space with poor ventilation, the risk of heat related illnesses, including heatstroke, is a serious concern. Heatstroke is a life-threatening condition that occurs when the body overheats and can no longer regulate its temperature. Left untreated, it can lead to organ failure, brain damage or even death.

WHAT IS HEATSTROKE?

Heatstroke is the most severe form of heat illness and occurs when the body’s core temperature rises to dangerous levels, typically above 40°C. Unlike heat exhaustion, which can often be managed with rest and hydration, heatstroke is a medical emergency requiring immediate intervention. High temperatures, humidity and prolonged exposure to heat can overwhelm the body’s cooling mechanisms, leading to heatstroke.

SIGNS AND SYMPTOMS OF HEATSTROKE

Recognising the symptoms of heatstroke early can mean the difference between life and death. The following signs indicate heatstroke and require urgent medical attention:

High body temperature: A core temperature above 40°C

Hot or dry skin: Sweating may stop, making the skin feel dry and hot to the touch

Confusion or disorientation: A person may appear confused, dizzy, or have difficulty thinking clearly

Rapid heartbeat and breathing: The body works harder to cool down, leading to an increased heart rate and fast, shallow breathing

Nausea and vomiting: Feeling sick or vomiting is common in heatstroke cases

Seizures or loss of consciousness: In severe cases, heatstroke can lead to fainting or even seizures.

If any of these symptoms appear, immediate action must be taken to cool the individual down and seek medical assistance.

TIPS TO PREVENT HEATSTROKE

Preventing heatstroke is far easier than treating it. Seafarers working in hot conditions should follow these essential precautions:

Stay Hydrated

Dehydration is a major risk factor for heatstroke. Drink plenty of fluids, preferably water or electrolyte-rich drinks, throughout the day. Provide cool drinks at the work site to allow seafarers to hydrate as necessary. Avoid excessive caffeine and alcohol, as they can contribute to dehydration. A good rule of thumb is to drink water even before feeling thirsty.

Plan for breaks in the shade

Prolonged exposure to direct sunlight, especially in tropical regions, can quickly lead to overheating. Where possible, schedule work to avoid the hottest part of the day. Before commencing work, highlight the dangers of heatstroke in a toolbox talk and the warning signs to be aware of. Plan for frequent breaks to allow personnel to cool down and recover.

Wear appropriate clothing for the environment

Personal Protective Equipment must be worn as required by company policy. However, when a ship trades regularly in hot and humid locations, consideration should be given to providing light-coloured, loose-fitting clothing made of moisture wicking materials to allow the body to cool more efficiently. A hat and UV-protective sunglasses can also help protect against excessive sun exposure and should be considered as part of any risk assessment prior to working in exposed areas.

Use cooling and protective measures

Apply a damp cloth to the neck, wrists and forehead to help cool down. When working at a static site, consider the rigging of temporary shading, or the provision of air blowers to help reduce the heat exposure of workers.

Apply sunscreen liberally at regular intervals to exposed skin. Skin that has not been exposed to sun for several months burns more easily.

Acclimatise to the Heat

Keep a close eye on new crew members or those returning from cooler climates. These crew members should be allowed time to adjust to the heat. Gradually increasing time spent in hot environments over several days can help the body adapt. This is particularly true of trainee or less experienced crew members.

Recognise and respond to early symptoms

If you or a colleague starts showing signs of heat exhaustion, such as heavy sweating, weakness, dizziness or nausea, take immediate action. Report this condition to the officer of the watch or your supervisor, move to a cooler area, hydrate and rest before symptoms worsen into heatstroke.

EMERGENCY RESPONSE TO HEATSTROKE

If a seafarer exhibits signs of heatstroke, immediate action is critical:

Move to a cooler area: Find shade, air-conditioning, or a cooler part of the ship to help lower body temperature

Cool the body rapidly: Apply ice packs to the armpits, groin, and neck, or immerse the person in cool water if possible

Encourage hydration if conscious: Offer cool water or electrolyte drinks but avoid caffeinated beverages

Call for medical help: If onboard, notify the ship’s medical officer or captain immediately. If onshore, seek emergency medical assistance

Monitor your colleague: Stay with the affected person and monitor their breathing and consciousness levels until medical assistance arrives.

Seafarers work in some of the most demanding environments, and the risks associated with heat exposure should never be underestimated. By recognising the signs of heatstroke, following prevention strategies, and responding quickly in emergencies, seafarers can protect themselves and their colleagues from heatstroke. Staying vigilant, hydrating regularly and respecting the dangers of excessive heat are key to ensuring a safe working environment.

BACK TO KNOWLEDGE