HazMat Tool — substance information

Zinc dithionite or Zinc hydrosulfite

HMT May 2026
UN / ID
UN 1931
Hazard class
9
Packing group
III
ERG guide
ERG 171
Special provisions
SP IB8, SP IP3, SP T1, SP TP33
Source
49 CFR §172 (2026/05)

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Zinc dithionite or Zinc hydrosulfite

Emergency Response Guide No. 171

Hazardous Materials Table

Source: 49 CFR §172 (2026/05)

(3) Hazard Class

9
Miscellaneous hazardous materials

(4) Identification number Help

UN 1931

(5) Packing Group Help

III

(6) Labels Help

None

(7) Special Provisions (§172.102) Help

×Note:
Special provisions may be very complex. The extracts are taken from 49 CFR §172.102. Please be careful with the information, as necessary, additional conditions may be applied that are not written here. Please check the original source and report bugs.
IB8
IP3
T1
TP33

(8) Packing Authorizations (§173.***) Help

(8A) Exceptions155see 49 CFR §173.155
(8B) Non-bulk204see 49 CFR §173.204
(8C) Bulk240see 49 CFR §173.240

(9) Quantity Limits Help

(9A) Passenger aircraft/rail100 kg
(9B) Cargo aircraft only200 kg

(10) Vessel stowage Help

(10A) Location
(10B) Other

Segregation chart for load, transport, and storage

This chart shows whether loading, transport, or storage with other hazard classes is permitted, prohibited, or restricted. Based on 49 CFR §177.848.

No compatibility information for class 9 in 49 CFR §177.848 included.

Scope & sources (important)Click to show CFR references

This check evaluates segregation per 49 CFR §177.848. Additional loading/unloading and handling requirements may still apply; see 49 CFR §177 Subpart B (Loading and Unloading):

  • §177.834 - General requirements
  • §177.835 - Class 1 materials
  • §177.837 - Class 3 materials
  • §177.838 - Class 4 (flammable solid) materials, Class 5 (oxidizing) materials, and Division 4.2 (pyroforic liquid) materials
  • §177.839 - Class 8 (corrosive) materials
  • §177.840 - Class 2 (gases) materials
  • §177.841 - Division 6.1 and Division 2.3 materials
  • §177.842 - Class 7 (radioactive) material
  • §177.843 - Contamination of vehicles