With summer approaching and temperatures beginning to climb, the risk of heat-related illnesses becomes a serious concern.
This is especially true for new and returning workers who haven’t had time to build up their heat tolerance. All employers have a responsibility to protect their teams by establishing and creating an environment where workers can gradually adjust to the heat and get used to working in hot conditions.
Why new workers are most at risk
According to OSHA, new workers are particularly vulnerable to heat stress during their first days on the job. That’s why it’s so important to put protection strategies in place from the start. These strategies include:
- Shorter work durations. Ease workers into the heat by following the "rule of 20%." On the first day, limit hot-weather work to just 20% of a full shift, then increase it by 20% each day over the course of a week.
- Frequent rest breaks. Provide more breaks during the day, especially during peak heat hours.
- Training. Educate workers on the symptoms of heat-related illnesses and the importance of hydration and proper rest.
- Close monitoring. Observe new workers closely for any signs of heat stress.
- Buddy system. Ensure new workers are paired with more experienced team members — no one should work alone in high heat.
- Responsive action. If a worker begins to feel unwell or shows symptoms, they should stop immediately, receive first aid and never be left alone.
These extra precautions should stay in place for at least the first one to two weeks, giving workers time to adjust to the heat safely.
Who’s new to working in the heat?
It’s not just new employees who are at risk of hot weather. Workers returning from extended leave — due to vacation, illness or seasonal breaks — may also lose their heat tolerance. Similarly, during seasonal temperature spikes, even experienced workers can be at risk if not gradually reintroduced to heat. In these situations, employers should apply the same protective measures they would for new hires.
Protecting new and returning workers from heat stress
Nearly half of all heat-related deaths happen on a worker’s first day — whether it’s their first day on the job or the first day back after being away for a while, and more than 70% of these deaths occur within the first week. This really highlights a significant fact: heat illness can strike quickly, especially when the body hasn’t had time to adjust. The good news is these tragedies are preventable. With a bit of planning and proactive measures, employers can make the workplace safer and greatly reduce the risk for workers during this critical time.
The term "workers new to warm environments" goes beyond just new hires. It includes temporary or long-term employees who are transitioning into new tasks that require physical exertion in the heat, those wearing heavy or heat-retentive protective gear and workers returning after any absence lasting a week or more. Even workers who have remained on the job may be at risk when a sudden heat wave hits or when temperatures begin rising in the spring or early summer.
That’s why having a solid acclimatization plan is so important. Employers should ease workers into the heat, provide extra breaks, keep water easily available and make sure supervisors know the warning signs of heat stress. Workers should be eased into conditions they can manage, without being thrust into anything too intense or unfamiliar. A buddy system and clear communication also go a long way in spotting issues early before they become serious.
Building a culture of heat safety
At the end of the day, creating a culture of heat safety is about more than just following rules — it’s about protecting people. When employers take the time to implement these practices, they’re not only preventing injuries and saving lives but also building trust, reducing turnover and developing a healthier, more productive team.
For more information, visit osha.gov.
