Florida’s Most Underestimated Danger

Heat stress isn’t just a summer problem. It’s a year-round threat, and most workplaces still aren’t doing enough.

TREEO Talk Recap · Heat Stress with Dr. John Diaz · May 18, 2026

Ask most Florida workers what they know about heat illness, and you’ll hear the same answer: drink water, stay in the shade. It’s not wrong, but it’s not nearly enough, and that gap is exactly where people get hurt.

On May 18, TREEO hosted its first TREEO Talk of the heat season: a free virtual session on heat stress featuring Dr. John Diaz, Associate Professor and Extension Specialist in the Department of Agricultural Education and Communication (AEC) at the University of Florida, with expertise in behavior change, community resilience, and occupational safety. Hosted by Cindy Mercado, the session was the official launch of TREEO’s Heat Illness Campaign, a series of resources, posts, and training opportunities designed to close the gap between what Florida workers know about heat and what they actually do about it.

Here’s what came out of that conversation — the first in a series of blogs and resources we’ll be rolling out all summer to help Florida workers and supervisors stay ahead of the heat.

Much of what shaped the conversation had been building for weeks. Cindy had been thinking through the campaign’s core message long before May 18, and the session itself brought those ideas to life with Dr. Diaz’s research and expertise.

Heat Illness Isn’t One-Size-Fits-All

One of the most important ideas framing this season’s campaign is that two people can stand in the exact same environment, doing the exact same work, and one of them is at dramatically higher risk than the other.

Individual risk factors like acclimatization level, underlying health conditions, medications, and fitness all affect how a body handles heat. A worker back from two weeks of vacation is not the same as someone who’s been on the job all summer. Treating everyone the same isn’t just ineffective — it’s how preventable emergencies happen.

The Gap Between Talking About It and Doing Something Effective

Cindy opened the session by putting the regulatory landscape into context. OSHA’s National Emphasis Program on Heat Hazards — originally issued in April 2022 and recently revised using data through 2025 — now targets 55 high-risk industries including agriculture, construction, manufacturing, and healthcare, for both indoor and outdoor workplaces. Compliance officers will prioritize inspections during heat advisories and warnings issued by the National Weather Service, and the updated program adds a formal framework for evaluating heat safety programs with citation guidance to back it up.

It’s a concern Cindy has been vocal about leading up to this campaign:

Heat safety plans that exist on paper but aren’t practiced. Supervisors who know the signs of heat exhaustion but haven’t built rest and shade into the workflow. Workers who don’t understand how fast heat illness can escalate until they’re watching it happen to a coworker. The OSHA updates are a step in the right direction — but compliance is a floor, not a ceiling.

Start in the Green Zone

Dr. Diaz set the stakes early in the session:

From there, he walked participants through a green, yellow, red framework for recognizing and responding to heat illness — and the message was clear: your goal every day is to stay in the green.

The Green Zone is about prevention. Water, rest, and shade are the foundation — and hydration means before and after your shift, not just during it. Dress in light-colored, loose-fitting, lightweight clothing, and give your body time to adjust if you’re new or coming back from time off. New and returning workers need 7 to 14 days to acclimatize before working at full intensity in the heat.

But prevention isn’t just personal — it’s a team effort.

When the body starts sending warning signs like fatigue, dizziness, cramps, nausea – that’s the Yellow Zone, and it demands a response. Push past it, and you’re in the Red: a medical emergency that can cause permanent damage or death. We break down exactly what to look for, and how to respond at each stage, in our next post.

What Actually Changes Behavior

It’s a reframe Cindy has returned to often in thinking about this campaign: someone once asked what they needed to buy to prevent heat stress — as if the answer were a product rather than a practice. It’s exactly the kind of thinking Dr. Diaz’s research is designed to shift. His work centers on behavior change and social marketing: how to move people from knowing something to actually doing something differently.

And perhaps the most grounding line of the session:

Behavioral change doesn’t come from a poster on the break room wall. It comes from workers who understand why their body responds the way it does to heat, supervisors who know how to read early warning signs in their crew, and organizations that have built heat safety into the rhythm of the workday, not just bolted it on as a compliance checkbox.

What This Means for Florida Workers Right Now

The season is already here. Here’s what every Florida worker and employer should take seriously:

• Heat illness is a spectrum, not a switch. Cramps, dizziness, headaches, and nausea are warning signs, not inconveniences. Ignoring early symptoms is how people end up in a medical emergency.
• Acclimatization is non-negotiable. New workers and workers returning from time off need a structured ramp-up period before they should be working full intensity in high-heat conditions.
• Electrolytes matter. As Dr. Diaz explained during the session, “Electrolytes are really some of the essential elements that help your body function.” Hydration is more than just drinking water — especially in Florida heat.
• Complacency is a risk factor. The “it won’t happen to me” mindset keeps workers from reporting symptoms and supervisors from acting quickly when they notice warning signs.
• Education is the most effective intervention. Not a product, not a single training — a culture where heat safety is understood, talked about, and practiced before the hottest part of the day arrives.

And perhaps the most important reminder from the session came down to listening to your body before the situation becomes dangerous:

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Learn More with UF TREEO

TREEO offers heat illness prevention training that goes beyond the basics — built for Florida’s industries and designed to change how workers and supervisors think and act in the heat.

Explore TREEO’s heat-related courses and resources on our Safety and Health program page, or contact Melissa Hamilton at melissajhamilton@treeo.ufl.edu to discuss training options for your team.