Phoenix-area school districts brace for extreme heat as students return to campuses, revising outdoor activity and bus safety protocols

Phoenix-area school districts revised outdoor activity and bus safety protocols this week as students returned to campuses amid extreme heat. According to the Arizona Department of Health Services, districts adopted written heat policies to limit outdoor exposure, assign monitoring responsibilities, and communicate changes to prevent heat-related illnesses.

The Arizona Department of Health Services (ADHS) recommends that all school districts adopt written heat policies to address outdoor activities during extreme heat, specifying actions for recess, physical education, field trips and sports practices, according to ADHS guidance. These policies are expected to assign clear roles and responsibilities for monitoring weather conditions and deciding when to modify or cancel outdoor activities to prevent heat-related illnesses. ADHS officials said keeping students in cooled indoor environments remains the most effective way to reduce heat risks and that communication procedures must be included to inform staff, students and parents of any changes during heat advisories or excessive heat warnings.

Several Phoenix-area districts have implemented or updated heat policies in line with these recommendations as students returned to campuses this week.

Deer Valley Unified School District (DVUSD) directs schools to keep students indoors as much as possible during heat advisories, using indoor facilities for physical activity. DVUSD guidelines instruct schools to schedule outdoor activities during the coolest parts of the day, limit activity duration, provide frequent breaks and ensure drinking water is available before, during and after outdoor exercise. The district uses a combined temperature and relative humidity index to determine activity modifications. When the heat index reaches the “Danger Zone” — defined as a combined temperature plus humidity of 136 to 145 or air temperature between 106 and 110 degrees Fahrenheit — outdoor practices may continue only with modifications such as reduced equipment and mandatory water breaks every 10 to 15 minutes. In the “Critical Zone,” with heat index values at or above 146 or air temperatures exceeding 111 degrees, DVUSD requires moving practices indoors, postponing or canceling competitions, eliminating running and equipment use, and maintaining frequent hydration breaks.

Other districts including Dysart, Peoria, Mesa and Kyrene have adopted similar policies, keeping students inside for recess and physical education when temperatures are “too high,” according to a recent Phoenix-area news report. Chandler Unified School District’s director of health services, Christine Bromley, said the district relies on the daily heat index issued by ADHS to determine when outdoor lunch and recess activities should be moved indoors. Many districts activate special heat precautions when temperatures exceed 110 degrees Fahrenheit, while some begin modifying recess activities at temperatures above 90 degrees, according to local media coverage and district sources.

ADHS guidance emphasizes the use of multiple environmental measures beyond ambient temperature alone, including humidity and radiant heat from surfaces, to assess risk levels. Districts often employ color-coded heat indices that incorporate humidity; when the index reaches “red,” students are required to remain indoors for all outdoor activities. The department also highlights hydration as a key prevention strategy. Arizona law mandates at least two drinking fountains per 100 students in kindergarten through eighth grade and one per 100 students in grades eight through twelve on school campuses. ADHS advises districts to install shade structures and position playgrounds to benefit from building shade, which can reduce surface temperatures close to air temperature. Shade can lower perceived temperatures by up to 15 degrees Fahrenheit, according to an ADHS report, supporting investments in shade sails, covered play areas and tree canopy. The department also recommends using natural surfaces where possible and minimizing asphalt and other heat-retaining materials to reduce heat exposure during outdoor activities.

Student behavior protocols are incorporated into district heat plans. ADHS and local districts urge students to apply sunscreen and lip balm, wear hats, sunglasses and light-colored clothing, and stay in shaded areas during peak UV hours. DVUSD advises students to hydrate before leaving home or school, carry water bottles during commutes, and drink fluids even when not feeling thirsty. Students are encouraged to pace physical activity, take frequent breaks, and recover in shaded or air-conditioned spaces after outdoor exertion. Parents are reminded to provide water and sun-protective clothing as temperatures rise late in the school year. City of Phoenix heat safety materials, which districts often reference, also recommend limiting outdoor activity during extreme heat, avoiding sugary or caffeinated drinks, and monitoring children for signs of heat exhaustion.

Transportation and bus safety protocols have also been updated to reduce heat exposure. ADHS recommends cooled indoor environments for students during transport, including air-conditioned school buses. DVUSD advises parents to drive children to and from school during extreme heat warnings when possible to reduce walking or biking exposure. Children who walk or bike are encouraged to travel with a buddy, wear light-colored, lightweight clothing, apply sunscreen to exposed skin, wear hats and carry water. Districts integrate arrival and dismissal procedures into heat plans, encouraging staff to minimize outdoor waiting times for buses and to use shaded or indoor waiting areas when temperatures are high. City of Phoenix guidance underscores planning transport and outdoor transitions for cooler times of day and ensuring hydration and sun protection during heat events.

ADHS also recommends training for teachers, coaches, bus drivers and support staff to recognize symptoms of heat-related illness and respond appropriately. Schools are advised to develop formal Emergency Action Plans (EAPs) for heat, including protocols for activating emergency medical services after initial cooling measures if heat illness is suspected. The department suggests incorporating a hierarchy of controls into heat policies, including elimination of outdoor play during extreme heat, engineering controls such as shade and cooling, administrative controls like schedule changes and activity limits, and personal protective measures including clothing and sunscreen.

Many Phoenix-area districts update or activate heat plans at the start of the school year to prepare for August and September heat waves, officials said. District health services and administrative staff monitor daily heat indices and local weather forecasts to adjust outdoor activity and bus protocols in real time, making decisions to call indoor recess or modify practices based on current risk levels.