There is no one-size-fits-all protocol for environmental conditions at horse shows. Discipline, venue layout and topography, and horse and human demographics all factor in the way heat can impact participants.
Please note: This guidance does not replace veterinary judgment, governing body rules, local emergency procedures, or official weather alerts. When there is uncertainty, decisions should prioritize horse welfare and human safety.
These guidelines are based on human and equine studies and are focused on the average healthy, fit equine. However, there are horses competing who would be considered a higher risk (older/younger or one with pre-existing medical problems such as respiratory disease), and their care team must monitor them for signs of distress.
Heat Impact on Horses and Humans
Horses maintain normal body temperature by moving heat from the muscles to the skin, where it can be released through blood flow, expanded blood vessels, and heat exchange through the lungs and skin. During exercise, heat production increases substantially and the horse relies primarily on sweat evaporation to dissipate excess body heat.
Cooling becomes less efficient when environmental conditions like elevated temperature or humidity limit sweat evaporation, which can raise the horse’s body temperature.
When a horse’s body temperature reaches 105F, the blood supply to their muscles begins to shut down. Subsequently, the blood supply to the intestines and kidneys, then brain and heart shut down, ultimately causing severe and permanent damage.
Heat stress is also a concern for people at equine events, including those in the saddle and on the ground. Prolonged time in direct sun, physical exertion, limited shade, dehydration, certain medications, and underlying medical conditions can increase the risk of heat exhaustion or heat stroke. Event plans should include human safety measures such as shade, drinking water, cooling areas, rest breaks, early communication, and clear procedures for recognizing and responding to heat illness in people.
Assessing Venue for Heat Mitigation Measures and Planning Ahead
Before the start of the competition, a site-specific assessment should be performed to determine venue specific risks and possible mitigation measures. You will need to consider shade and water availability, air movement, sun exposure, and arena surface, as well as population factors like crowd density and horse and human risk groups. Keep in mind that these factors may vary greatly across portions of the venue. For example, a facility that has variations in tree cover or elevation may have very different heat and humidity between competition or stabling areas.
Plan your heat mitigation efforts in advance. Mitigation should begin before horses show distress and should escalate as heat conditions worsen, especially when shade, airflow, cooling water, or veterinary response capacity are limited.
- Establish cooling stations: Place these near arenas, warm-up rings, lunging areas, finish areas, barns, and trailer parking with plentiful cool water, hoses, scraping tools, shade, and safe airflow from fans or natural ventilation
- qIncrease water availability: Ensure continuous access to clean drinking water and separate cooling water; check water pressure, hose access, and back-up supply before and during competition. From a biosecurity perspective, communal water troughs are not recommended, but you should provide hoses that can used to fill individual water buckets. Individuals should bring dedicated horse buckets to the area to be filled.
- Expand shade and airflow: Use tents, shade structures, trees, open-sided barns, aisle fans, and cross-ventilation to reduce solar exposure and heat build-up in stabling, waiting areas, and warm-up spaces.
- Modify the schedule: Move strenuous classes to cooler parts of the day, add longer breaks, reduce warm-up duration, shorten schooling periods, delay affected divisions, or reschedule/cancel classes and close lunging areas when conditions exceed safe thresholds.
- Reduce exercise load: Limit unnecessary schooling, restrict prolonged warm-up and lunging, manage ring congestion, reduce wait times in direct sun, and prioritize rapid recovery after work. Additional staffing recommended to monitor lunging areas for excessive lunging during the severe heat.
- Increase veterinary and steward observation: Position stewards and trained personnel at high-risk locations (competition, warm up and lunging areas) to identify horses with delayed recovery, rapid breathing, weakness, dehydration, abnormal sweating, or other signs of heat stress.
- Support high-risk horses: Encourage additional precautions for senior, young, unfit, non-acclimated, dark-coated, heavily muscled, or medically vulnerable horses, including reduced exertion and longer recovery time.
- Be ready to communicate early and often: Have a plan for notifying competitors, trainers, grooms, officials, vendors, and staff of heat risk status, cooling station locations, schedule changes, withdrawal options, emergency procedures, and signs that require veterinary attention.
- Prepare emergency response: Confirm the event veterinarian’s location and contact method, maintain clear access routes for emergency vehicles and veterinary teams, identify shaded treatment areas, and document heat-related incidents and actions taken.
- Escalate decisively: If cooling resources are overwhelmed, readings continue to rise, or veterinary/official review determines conditions are unsafe, stop, delay, reschedule, or cancel affected competition.
Human heat illness mitigation: Event management should plan for people as well as horses by providing shaded rest areas, clearly marked drinking-water locations, cooling towels or misting areas when feasible, and scheduled rest breaks for staff, volunteers, officials, and other personnel working outdoors. High-risk tasks should be rotated or moved to cooler parts of the day when possible, and all event personnel should know how to recognize early signs of heat illness, where to find cooling resources, and how to activate emergency medical response if a person develops confusion, collapse, persistent vomiting, or other severe signs.
Heat Monitoring Plan During USEF Competition: Wet Bulb Globe Temperature (WBGT)
During competition, you should take measurements on-site, rather than relying on weather data that may be collected several miles away in a different environment than what you have at the show.
- Preferred measure: Wet Bulb Globe Temperature (WBGT). The WBGT Index is a validated heat index for equestrian sport because it takes into account air temperature, humidity, direct sun rays and wind.
We have updated our guidance to use WBGT where possible rather than the previously-recommended measure of heat index. WBGT is used in a wide variety of sports because it takes into account a greater range of local environment variabilities and US Equestrian believes it more accurately captures the way the temperature feels at a specific site. - Minimum monitoring frequency: Every three hours when conditions are mild; hourly when risk is elevated with rapid changes or high readings.
- Monitoring locations: Relevant areas for measurements across field of play with the final average of the three location readings.
- Recordkeeping: Document time, location, WBGT reading, wind/airflow, cloud cover, footing condition, and actions taken.
- Decision Making: Decisions should be made a minimum of 90 minutes before start of competition. If a break in competition is taken as mitigation measure break must be a minimum of 90 minutes.
Recommended WBGT Measuring Device: The USEF has tested several wet bulb globe temperature devices recommends this device for equestrian competitions: Protmex PT6508 Temperature Humidity Meter- Wet Bulb for Indoor/Outdoor.
For events which don’t yet have a WBGT device, the following charts can be used to convert local Fahrenheit readings to Celsius and to estimate the WBGT index.
Risk Categories and Recommended Actions
- Continue with monitoring when risk is low and mitigation resources are adequate.
- Activate heat mitigation when WBGT approaches 28°C.
-
Modify schedule or format when WBGT approaches 30°C, especially for strenuous disciplines, limited shade, poor airflow, or non-acclimated horses.
-
Delay, reschedule, or cancel affected classes when WBGT exceeds 32.2°C, unless veterinary and official review determines that conditions can be managed safely with robust mitigation.
-
Stop competition immediately if cooling resources fail, emergency response capacity is overwhelmed, or officials/veterinary staff determine conditions are unsafe.
-
Staff oversight of horses during any breaks or cancellations should ensure horses are not being worked or lunged under unhealthy conditions.
Heat Stress in Horses
Encourage competitors and competition personnel to monitor horses for signs of heat stress. These can include:
- Elevated rectal temperature. A temperature of 105–107°F warrants an emergency response and veterinary evaluation.
- Rapid breathing or pulse that does not improve when exercise stops or with cooling efforts.
- Weakness, stumbling, or lack of coordination.
- Dry skin, lack of sweating, skin tenting, tacky gums, or dark urine.
- Failure to respond to cooling efforts.
If you notice these symptoms at times of high heat:
- Stop exercise or competition immediately.
- Move the horse to shade or the nearest safe cooling area with air movement.
- Remove tack and equipment as soon as safe and practical.
- Begin active cooling with cool water; repeat application continuously as directed by veterinary personnel.
- Offer water when safe and appropriate; do not force drinking.
- Notify the event veterinarian and provide location, horse identification, signs observed, and time signs began.
- Control the area so the veterinary team has clear access, and the horse is protected from crowding.
- Document the event, actions taken, response time, and outcome.
Communications Template for Competition Managers
Pre-Event/Prize List Notice
Hot weather is forecasted during our competition. Event management will monitor on-site conditions throughout the day and may adjust ride times, warm-up access, breaks, or class schedules to protect horse and human safety. Please bring appropriate cooling supplies such as extra buckets, ice, fans, and any human cooling gear, monitor your horse closely, use shade and water resources, and watch for signs of heat stress. Report any signs of heat stress to the show veterinarian immediately. We will be taking temperature readings at multiple points across the venue to help us get a complete picture of how the surface, wind, shade cover, etc. are impacting heat.
Heat Advisory Announcement
Attention competitors: We continue to monitor the heat using Wet Bulb Global Temperature measurements and want to advise caution during today’s event. Please reduce unnecessary warm-up time, use cooling stations promptly after exercise, keep horses in shade when possible, and monitor them for rapid breathing, rapid pulse, weakness, stumbling, dry skin, dehydration, or failure to recover. Event officials and veterinary staff are taking readings and monitoring conditions around the property and will provide updates as needed on [event website and social media]. If readings become too high or cooling efforts are no longer impactful, we will need to delay or reschedule competition. If there is a stoppage in competition, there will be a minimum of 2 hour notice of resumption of activities.
Schedule Modification Notice
Due to current heat conditions, event management is modifying the schedule to protect our horses and our competitors. [Affected classes] will be delayed/shortened/moved to a cooler time of day. Thank you for your patience. Please stay tuned for further updates.
If you have questions about this guidance or need details about how to apply it to your venue, please email [email protected].