Every spring in Arizona, the heat comes fast—and for employers with outdoor crews, the operational challenge arrives right alongside legal and safety risk. If you’re a contractor, subcontractor, or business owner whose people work outside (or inside structures without meaningful cooling), it’s time to refresh your heat plan before the first 105° day hits.
Here’s the good news: the playbook is clear. There are proven controls that reduce heat illness, improve productivity, and demonstrate compliance if an incident occurs. And there have been meaningful policy developments in Arizona over the past year that make heat safety even more important for employers to treat as a formal program, not an informal “drink water and tough it out” approach.
What changed in Arizona over the past year?
1) Phoenix’s contractor-focused heat ordinance is now the clearest “must-do” rule for covered employers.
Phoenix adopted a worker safety ordinance aimed at contractors working under City contracts, leases, or licenses, and it explicitly extends through required contract language to subcontractors and downstream parties. View the Phoenix Worker Safety Ordinance
In plain terms: if you do work on City-owned/leased/licensed property (including City streets/rights-of-way), you should assume you’re covered, or that you may become covered if you bid City work in the future.
The ordinance requires a written heat safety plan kept on file, posted where employees can access it, and available to the City upon request, along with documentation of mitigation efforts.
2) Arizona launched a new state-level Heat Safety Task Force (Executive Order 2025-09)
On May 22, 2025, Governor Hobbs signed Executive Order 2025-09, directing the Industrial Commission of Arizona (ICA) and ADOSH to form a Workplace Heat Safety Task Force to draft and recommend heat guidelines for employers by December 31, 2025, with the goal of having guidelines in place before summer of 2026 (after ICA review/approval). View ICA FAQs
These guidelines are not law yet—but they matter. The ICA/ADOSH FAQ explains that the guidelines are intended to clarify what constitutes a heat hazard under the OSHA General Duty Clause, as enforced by ADOSH, and to provide more consistent expectations for employers.
3) Federal OSHA Heat Rulemaking: A Sign of What’s Coming
OSHA’s federal heat standard hasn’t taken effect yet, but it moved forward again over the past year—OSHA issued a proposed “Heat Injury and Illness Prevention” rule and then held public hearings into mid-2025. Even though Arizona employers aren’t required to follow a final federal heat rule today, this signals where enforcement expectations are headed (written plans, training, water/rest/shade, acclimatization, and clear response procedures) and makes it even more important to treat heat safety as a documented program rather than informal guidance.
Phoenix ordinance: the core requirements contractors should know
Phoenix’s ordinance is highly practical: it outlines what must be in your plan and what your workforce must have access to. Key elements include:
- A written heat safety and mitigation plan. Must be kept on file, posted where accessible, and available to the City upon request.
- Water. Availability of sanitized cool drinking water, free of charge, accessible to all covered workers.
- Rest and breaks. Ability to take regular and necessary breaks, plus additional hydration breaks as needed.
- Shade and/or air conditioning. Access to shaded areas and/or air conditioning for recovery.
- Air conditioning. Vehicles with enclosed cabs must have functioning A/C.
- Acclimatization. Practices that support physiological adaptation for workers newly assigned/reassigned to outdoor heat.
- Training. Training must be made available and understandable to workers and cover: risk factors, prevention, recognition/reporting of symptoms, first aid, and reporting to emergency medical personnel.
- Documentation and downstream compliance. City may request documentation of mitigation efforts; contractors must flow requirements down to subcontractors and ensure compliance.
- Penalties for noncompliance. After notice and an opportunity to cure, sanctions may include cancellation/termination/suspension of a contract or suspension/debarment.
Best practices for contractors with outdoor laborers
Whether or not you’re currently covered by Phoenix’s ordinance, these practices reduce incidents and help demonstrate a defensible safety program if something goes wrong.
1) Use a simple heat trigger system. Pick a threshold that increases protections as heat rises (for example: “heightened controls at 90°F, maximum controls at 100°F+”). Consistency is more important than picking the perfect number. Tie triggers to:
- Extra rest breaks
- Shorter work cycles
- Increased supervisor check-ins
- More shaded recovery space
- Start-time adjustments
2) Treat acclimatization as a process, not a suggestion. Most heat illnesses occur early in exposure. Build a ramp-up for:
- New hires
- Employees returning from time off
- Employees moving to hotter tasks
- Phoenix explicitly expects acclimatization practices.
3) Engineer cooling wherever possible. Administrative controls help, but physical/engineered controls prevent exposure:
- Shade canopies at fixed outdoor stations
- Fans/misters (where appropriate)
- Cooled trailers or indoor recovery rooms
- Vehicle A/C maintenance schedules (especially for enclosed cabs)
4) Make water access frictionless. “Water available” is not the same as “water used.” Place water where crews actually are, refresh it, and normalize hydration breaks. Phoenix requires sanitized, cool drinking water, free and accessible.
5) Train for recognition and response—and make it practical. Your training should be short, repeatable, and bilingual where needed. Phoenix expects training that covers recognition/reporting of symptoms, first aid, and emergency escalation.
Add practical components:
- What heat exhaustion looks like on your jobsite
- “Stop work” authority for supervisors
- Buddy system checks
- When to call 911 vs. transport
6) Build an incident-ready response plan. At 110°F, the difference between “we’ll figure it out” and a documented response plan is huge. Your plan should identify:
- Who makes the call to stop work
- How you contact EMS
- The nearest cross streets / GPS pin for remote sites
- Who guides EMS to the patient
- Cooling steps while waiting (move to shade/AC, remove excess PPE if safe, cool with water/ice packs)
7) Document what you do. Phoenix explicitly contemplates documentation requests.
Simple logs go a long way:
- Heat index/temperature and work schedule adjustments
- Water delivery/placement checks
- Training sign-offs
- A/C maintenance records
- Break schedules and shaded recovery availability
- Acclimatization schedules for new/returning workers
Final thought: heat safety is a risk management advantage
Heat illness prevention isn’t just compliance—it’s fewer injuries, fewer delays, better retention, and better outcomes in claims and liability scenarios. And with Phoenix’s ordinance in effect and Arizona’s new task force pushing toward statewide guidelines, documented heat programs are rapidly becoming the standard of care.
If you would like assistance creating or modifying your heat illness safety plan, reach out. We would be happy to help.
References
https://www.phoenix.gov/administration/departments/heat/heat-response-programs/worker-safety-ordinance.html “Worker Safety Ordinance | City of Phoenix”
https://www.azica.gov/sites/default/files/2025-05/FAQ%20Workplace%20Heat%20Safety%20Task%20Force%20%2B%20Guidelines%20.pdf “FAQ Workplace Heat Safety Task Force + Guidelines “
https://www.osha.gov/heat-exposure/rulemaking/?utm_source=chatgpt.com “Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings …”