Concerns of fire depts and exposures with BESS fires and new standards

New Firefighter Training Standards

Several organizations have developed new safety standards in regard to BESS and solar farm fires

National Fire Protection Association

Key standards include:

• NFPA 855 – installation requirements for energy storage systems
• NFPA 13 – fire suppression systems
• NFPA 70 (National Electrical Code) updates for batteries

These standards include spacing, fire barriers, and ventilation requirements.

UL Solutions

• UL 9540A testing

This test evaluates how batteries behave during thermal runaway propagation and helps engineers design safer systems Does Barrett use this ??

Why Fire Departments Are Concerned About BESS Fires

1. Thermal runaway cannot be easily extinguished – occurs more often in hot outside temps 

Once lithium-ion batteries enter thermal runaway, the reaction inside the cell can continue even after water is applied.

Challenges include:

•  Internal chemical reactions keep generating heat
• Fires may reignite hours or days later
• Containers may burn for 12–48 hours or longer

Firefighters often switch to cooling surrounding equipment rather than trying to extinguish the battery directly.

2. Explosion hazards from gas buildup

Battery failures release flammable gases such as:

• hydrogen
• methane
• carbon monoxide
• ethylene
• hydrogen fluoride
• If gases accumulate inside a container and ignite, explosions can occur.

A well-known example occurred at the McMicken Battery Energy Storage System in 2019, where an explosion injured eight firefighters.

3. Toxic gas exposure

Battery fires can release:

• hydrogen fluoride
• phosphoryl fluoride
• metal particulates

Hydrogen fluoride is particularly concerning because it can cause

• severe lung irritation
• chemical burns
• delayed pulmonary injury.

Because of this, SCBA respirators are mandatory. Many environmental scientists advise resident who move within a 1/4 mile had these respirators 

4. Electrical hazards

Large battery facilities may contain:

• tens or hundreds of megawatt-hours of stored energy
• high-voltage DC systems

Even after shutdown, components may remain energized.

Firefighters must maintain safe electrical distances.

5. Long-duration fires

Unlike normal structure fires, battery fires may require:

• multi-day monitoring
• continuous cooling
• environmental air monitoring.
• Strategy for BESS

1. Typical emergency protocol now includes:
   1. Establish a large safety perimeter
   2. Do not open battery containers
   3. Use gas detection equipment
   4. Apply water to cool adjacent units
   5. Allow damaged modules to burn out if necessary
   Many departments use a defensive strategy instead of aggressive interior firefighting.
   Improvements in newer battery installationsDoes Barrett have these ??!Modern systems now include safety features such as:
   • automatic gas detection
   • explosion venting panels
   • thermal barriers between battery modules
   • automatic suppression systems
   • remote monitoring of each battery cell.
   These improvements were introduced after early incidents.
   
   Water required to cool units  from the Littleton, Massachusetts Fire Department for a containerized BESS thermal event. Their planning ranges are:
   • One BESS container: often plan roughly 60,000–120,000 gallons
   • More difficult single-container event: 120,000–360,000 gallons for an extended single-container event with prolonged heating or limited access
   Large fire in very large, long-duration incidents, the number can be far higher. Reporting on the Gateway fire in San Diego County said crews pumped about 8 million gallons, but that was to cool surrounding structures and manage smoke over many days, not a typical single-unit cooling event.