Delaware2025Passed Legislature
HB479
Community Heat Protection and Industrial Accountability Act
Last scannedAug 24, 2026, 10:01 AM
In one sentence
This law requires certain commercial operations in Delaware to stop or reduce activities that raise nearby residential temperatures by more than 2 degrees Fahrenheit during extreme heat events.
What it does
- Requires commercial facilities that significantly increase local outdoor temperatures to pause work or fix the problem when a heat warning is active.
- Sets a limit where any facility raising local outdoor temperature by over 2.0 degrees Fahrenheit must take action.
- Orders the Department of Natural Resources and Environmental Control (DNREC) to create rules for measuring how much heat businesses release into neighborhoods.
- Allows DNREC to fine violators up to $10,000 per day or order them to shut down completely.
- Gives residents living near these facilities the right to file a lawsuit if they are harmed by rule violations.
Who it affects
- Commercial operations such as data centers and manufacturing plants that emit waste heat into residential areas.
- Residents in neighborhoods where commercial activities raise local temperatures during extreme weather.
- The Delaware Department of Natural Resources and Environmental Control (DNREC), which must enforce the rules.
Limits and unknowns
- Facilities zoned for heavy industrial use, such as oil refineries, are exempt from these rules unless they are data centers.
- The specific methods for measuring heat and the exact enforcement steps will not be final until DNREC writes new regulations within 18 months.
Plain language
Terms to know
- Thermal impact threshold
- A rise in outdoor temperature greater than 2.0 degrees Fahrenheit caused by a specific business operation within a residential area.
- Mitigation measures
- Changes to technology or operations that lower heat emissions below the allowed limit.
- Private right of action
- The legal ability for an individual person to file a lawsuit against a business for breaking this law.
Official record
Sources
Official summary
AN ACT TO AMEND TITLE 7 OF THE DELAWARE CODE RELATING TO COMMERCIAL OPERATIONS.