ERG 2024 · Guide 135

Substances - Spontaneously Combustible

UN2318 · Sodium hydrosulfide, with less than 25% water of crystallization

Also listed as: Sodium hydrosulphide, with less than 25% water of crystallization

Class 4.1

Flammable Solid placard (DOT 49 CFR §172)

CHEMTREC · 24/7

1-800-424-9300

Right now: Move upwind. Isolate 100 m minimum. Deny entry. Call CHEMTREC with shipping paper in hand.

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Potential Hazards

Health

Fire will produce irritating, corrosive and/or toxic gases.
Inhalation of decomposition products may cause severe injury or death.
Contact with substance may cause severe burns to skin and eyes.
Runoff from fire control or dilution water may cause environmental contamination.
CAUTION: Pentaborane (UN1380) is highly toxic and may be fatal if inhaled, ingested or absorbed through skin.

Fire or explosion

Flammable/combustible material.
May ignite on contact with moist air or moisture.
May burn rapidly with flare-burning effect.
Some react vigorously or explosively on contact with water.
Some may decompose explosively when heated or involved in a fire.
May re-ignite after fire is extinguished.
Runoff may create fire or explosion hazard.
Containers may explode when heated.

Public Safety

General

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.
Stay upwind, uphill and/or upstream.
Keep unauthorized personnel away.

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.
Spill
For highlighted materials: see Table 1 - Initial Isolation and Protective Action Distances.
For non-highlighted materials: increase the immediate precautionary measure distance, in the downwind direction, as necessary.
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.

Emergency Response

Fire

DO NOT USE WATER, CO2 OR FOAM ON MATERIAL ITSELF.
Some of these materials may react violently with water.
CAUTION: For Xanthates, UN3342 and for Dithionite (Hydrosulfite/Hydrosulphite) UN1384, UN1923 and UN1929, USE FLOODING AMOUNTS OF WATER for SMALL AND LARGE fires to stop the reaction. Smothering will not work for these materials, they do not need air to burn.

Small Fire

Dry chemical, soda ash, lime or DRY sand, EXCEPT for UN1384, UN1923, UN1929 and UN3342.

Large Fire

DRY sand, dry chemical, soda ash or lime EXCEPT for UN1384, UN1923, UN1929 and UN3342, or withdraw from area and let fire burn.
CAUTION: UN3342 when flooded with water will continue to evolve flammable Carbon disulfide/Carbon disulphide vapors.
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

Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles.
Do not get water inside containers or in contact with substance.
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

CAUTION: For spills of Xanthates, UN3342 and for Dithionite (Hydrosulfite/Hydrosulphite), UN1384, UN1923 and UN1929, dissolve in 5 parts water and collect for proper disposal.
CAUTION: UN3342 when flooded with water will continue to evolve flammable Carbon disulfide/Carbon disulphide vapors.
Cover with DRY earth, DRY sand or other non-combustible material followed with plastic sheet to minimize spreading or contact with rain.
Use clean, non-sparking tools to collect material and place it 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.