Florida's Policy 41, Exertional Heat Illness, goes further than any other state heat policy. It sets WBGT thresholds for practices, a separate set of modifications for contests broken out sport by sport, mandatory cooling zones with cold-water immersion at every outdoor session, and a 14-day acclimatization period covering all sports.
It is also the only one standing on its own statute. The Zachary Martin Act, named for a Fort Myers student who died of heat stroke after a 2017 football practice, put parts of these requirements into Florida law, so compliance is not purely an association matter.
FHSAA WBGT thresholds for practice
Modifications are fluid: as conditions worsen they tighten, and as conditions improve they may be relaxed again.
- Normal activities.
- Three separate four-minute breaks per hour of activity.
- Maximum two hours of activity.
- Four separate four-minute rest breaks per hour.
- Football: restricted to helmet, shoulder pads and shorts.
- If the reading rises to this level after practice began, athletes may continue in football pants without changing into shorts.
- Maximum one hour of activity.
- Five separate four-minute rest breaks.
- No protective equipment permitted. No conditioning activities permitted.
- No outdoor activities.
How Florida requires the reading to be taken
Policy 41 is unusually specific about device placement, and the specificity matters: a device in the shade describes a situation nobody is in.
- A WBGT device must be used whenever the reading is reasonably expected to exceed 82°F.
- Set the device up and let it acclimatize at the venue for 15 to 20 minutes before activity starts.
- Place it three feet above the surface of the field or turf, away from obstructions.
- Set it up in the sun, not under shade. In a non-climate-controlled building, switch the device to indoor mode.
- Monitor approximately every 30 minutes throughout the practice or event.
- If the reading moves into a different zone, change the modifications to match, in either direction.
Cooling zones are required at every session
This is the requirement that distinguishes Florida most sharply. A cooling zone must be available for every outdoor athletic contest, practice, workout or conditioning session, and it must include the immediate availability of cold-water immersion tubs or equivalent, such as tarp-assisted cooling.
An individual trained to administer cold-water immersion must be present at the location of the equipment. Schools must also have an adequate ice supply immediately available, and alternative onsite safeguards where ice is not readily accessible.
There is no WBGT threshold on this one. It is every session, regardless of the reading.
Contests have their own rules
Most state policies govern practice and leave games to judgment. Florida writes the contest modifications out by sport in Policy 41.9.5.
At 82.1 to 87.0°F, football must provide a minimum two-minute rest break per quarter at a reasonable break in action, and the host team must have a cold-water immersion modality ready on site. Cross country requires two separate hydration stations placed through the course.
At 87.1 to 90.0°F, football takes a mandatory three-minute hydration break at or near the six-minute mark of each quarter. All participants remove helmets and no coaches are permitted on the field during it. Soccer takes a three-minute break near the 20-minute mark of each half.
School personnel who measure WBGT must provide the data to the principal or designee in advance of any event where heat may be a factor, and modifications up to and including postponement are explicitly on the table.
Acclimatization and practice definitions
- The acclimatization period is the first 14 calendar days of an athlete's participation, and all FHSAA sports are included.
- Athletes arriving after the first official day of practice still get the full acclimatization protections, counted from their own start.
- An official practice is no more than three hours and no more than 90 minutes of intense exercise, including warm-up, stretching and cool-down.
- A walk-through must not exceed one hour, with no protective equipment and no conditioning or weight-room activity.
- Physical activity is restricted during the recovery period between sessions, and walk-throughs are prohibited during it.
- All head coaches, supplemented coaches and student athletes must annually complete the free NFHS Heat Illness Prevention course.
This policy requires an on-site WBGT instrument. A phone app does not satisfy it, and the WBGT app should not be used as the compliance reading here. Use it to plan the week, check conditions before you travel, and sanity-check a device you suspect is reading wrong. Policy 41 specifies an on-site WBGT device, including where to place it and how long to let it acclimatize.
Warning signs of heat illness
Heat stress shows up before it becomes an emergency. Anyone on site should speak up immediately on any of these:
When in doubt, cool first and call for help. Collapse or confusion in the heat should be treated as possible exertional heat stroke: begin cold-water immersion immediately and call 911. Cooling comes before transport.
Forecast the Florida heat before the schedule is set
Policy 41 governs what happens at the venue. The app covers the part it does not: what next week looks like, so practices and contests can be scheduled around the heat rather than modified on arrival.
- Real-time WBGT for your location or any city
- Hourly and 14-day WBGT forecasts to plan ahead
- Color-coded flag levels with mode-specific guidance
- Humidity, wind, sun and cloud cover behind every reading
WBGT is estimated from weather data with the peer-reviewed Liljegren model. Where a policy requires on-site measurement, use the app for planning and as a cross-check alongside your instrument.
Common questions
What WBGT stops outdoor activity in Florida?
92.1°F WBGT and above. FHSAA Policy 41 permits no outdoor activities at that level. From 90.1°F activity is capped at one hour with five four-minute rest breaks and no protective equipment or conditioning.
What is the Zachary Martin Act?
A Florida law named for a student who died of exertional heat stroke after a 2017 football practice. It places heat safety requirements, including environmental monitoring and on-site cooling, into state law rather than leaving them to association policy alone.
Does FHSAA require cold water immersion tubs?
Yes, at every outdoor contest, practice, workout or conditioning session, with no WBGT threshold attached. The cooling zone must include immediate availability of cold-water immersion or equivalent, and a person trained to administer it must be present at the equipment.
Where does the WBGT device have to be placed in Florida?
Three feet above the field or turf surface, away from obstructions, in the sun rather than shade, allowed to acclimatize at the venue for 15 to 20 minutes before activity. Indoors in a non-climate-controlled space, the device is switched to indoor mode.
Does the FHSAA heat policy apply to games as well as practices?
Yes. Policy 41.9.5 sets separate contest modifications sport by sport, including mandatory hydration breaks in football and soccer and required cold-water immersion provided by the host team.
How long is the Florida acclimatization period?
Fourteen calendar days from the athlete's first participation, covering all FHSAA sports. Practices are capped at three hours with no more than 90 minutes of intense exercise.
Related WBGT guides
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