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United Nations/North American Number Datasheet

UN/NA 1923

4.2 - Spontaneously combustible

Emergency Response Guidebook (ERG, 2016)

Material Names

  • Calcium dithionite
  • Calcium hydrosulfite
  • Calcium hydrosulphite
ERG book cover

Response Guide 135

Substances - Spontaneously Combustible Sustancias - Espontáneamente Combustibles Substances - Spontanément Inflammables

 

ERG Table 1: Initial Isolation and Protective Action Distances

Name of Material Small Spills
(from a small package or small leak)
Large Spills
(from a large package or many small packages)
First
Isolate
in all Directions
Then Protect Downwind First
Isolate
in all Directions
Then Protect Downwind
Day Night Day Night
Calcium dithionite (when spilled in water) 100 ft 0.1 mi 0.4 mi 200 ft 0.4 mi 1.4 mi
Calcium hydrosulfite (when spilled in water) 100 ft 0.1 mi 0.4 mi 200 ft 0.4 mi 1.4 mi
Calcium hydrosulphite (when spilled in water) 100 ft 0.1 mi 0.4 mi 200 ft 0.4 mi 1.4 mi

ERG Table 2: Water-Reactive Materials which Produce Toxic-By-Inhalation Gases

When spilled in water, large amounts of Hydrogen sulfide (H2S) and Sulfur dioxide (SO2) may be produced.

Hazmat Table (49 CFR 172.101)

UN/NA Proper Shipping Name Hazard Class Labels Notes*

* There are three notes: (1) whether the displayed information is for domestic (U.S.) or international shipping (if neither is specifically indicated, it applies to both), (2) whether the proper shipping name must include one or more technical names of the hazardous material in parentheses, and (3) whether the hazardous material is an inhalation hazard.
UN Calcium dithionite or Calcium hydrosulfite 4.2 4.2

  4.2 - Spontaneously combustible