# Guide 149: Substances (Self-Reactive)

**Citation:** ERG 2024 Guide 149  
**Type / status:** guidance / guidance  
**Agency:** U.S. DOT / Transport Canada / SICT  
**Effective:** Not stated  
**Published:** 2024-04-04

ERG2024 response Guide 149: Substances (Self-Reactive).

## Document text

GUIDE
149
Substances (Self-Reactive)
POTENTIAL HAZARDS
FIRE OR EXPLOSION
•
Self-decomposition, self-polymerization, or self-ignition may be triggered by heat, chemical
reaction, friction or impact.
•
May be ignited by heat, sparks or flames.
•
Some may decompose explosively when heated or involved in a fire.
•
Those substances designated with a (P) may polymerize explosively when heated or involved in a fire.
•
May burn violently. Decomposition or polymerization may be self-accelerating and produce large
amounts of gases.
•
Vapors or dust may form explosive mixtures with air.
•
•
•
HEALTH
Inhalation or contact with vapors, substance or decomposition products may cause severe injury or
death.
May produce irritating, toxic and/or corrosive gases.
Runoff from fire control or dilution water may cause environmental contamination.
PUBLIC SAFETY
CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper
not available or no answer, refer to appropriate telephone number listed on the inside back cover.
Keep unauthorized personnel away.
Stay upwind, uphill and/or upstream.
•
•
•
PROTECTIVE CLOTHING
•
Wear positive pressure self-contained breathing apparatus (SCBA).
•
Wear chemical protective clothing that is specifically recommended by the manufacturer when there is
NO RISK OF FIRE.
•
Structural firefighters' protective clothing provides thermal protection but only limited chemical protection.
EVACUATION
Immediate precautionary measure
•
Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters
(75 feet) for solids.
Large Spill
•
•
Consider initial evacuation for at least 250 meters (800 feet) in all directions.
Fire
If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all
directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions.
Page 228
ERG 2024

Substances (Self-Reactive)
GUIDE
149
EMERGENCY RESPONSE
FIRE
Small Fire
•
Dry chemical, CO2, water spray or regular foam.
Large Fire
•
Flood fire area with water from a distance.
•
•
If it can be done safely, move undamaged containers away from the area around the fire.
Fire Involving Tanks, Rail Tank Cars or Highway Tanks
BEWARE OF POSSIBLE CONTAINER EXPLOSION.
•
Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles.
•
Cool containers with flooding quantities of water until well after fire is out.
•
Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank.
•
ALWAYS stay away from tanks in direct contact with flames.
SPILL OR LEAK
•
ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.
•
Do not touch or walk through spilled material.
•
Stop leak if you can do it without risk.
Small Spill
•
Pick up with inert, damp, non-combustible material using clean, non-sparking tools and place into loosely
covered plastic containers for later disposal.
•
Prevent entry into waterways, sewers, basements or confined areas.
FIRST AID
Refer to the “General First Aid” section.
In Canada, an Emergency Response Assistance Plan (ERAP) may be required for this product.
Please consult the shipping paper and/or the "ERAP" section.
ERG 2024
Page 229

## Provenance

- Official: Yes
- Source: <https://www.phmsa.dot.gov/erg/guide?number=149>
- Source ID: `phmsa-erg-2024`
- SHA-256: `f2367e8e958468efc7c364d4c3c945bbb1d970b1a07469c4d3f4bde09430b9a8`
- Retrieved: 2026-08-13T11:31:32.574Z
- Exported: 2026-08-22T23:10:24.608Z
- Document slug: `phmsa-erg-2024-guide-149`

### Source metadata

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