HazMat Tool — substance information

Fulminic acid

HMT 15 June 2026

UN / ID: n/a
Hazard class: Forbidden
Packing group: —
ERG guide: —
Special provisions: —
Source: 49 CFR §172 (15 June 2026)

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Fulminic acid

Fulminic acid is an acid with the formula HCNO, more specifically H−C≡N+−O−. It is an isomer of isocyanic acid (H−N=C=O) and of its elusive tautomer, cyanic acid (H−O−C≡N), and also of isofulminic acid (H−O−N+≡C−). Fulminate is the anion Wikipedia

Hazardous Materials Table

Source: 49 CFR §172 (15 June 2026)

(3) Hazard Class

Forbidden

(4) Identification number

n/a

(5) Packing Group

n/a

(6) Labels

n/a

(7) Special Provisions (§172.102)

(8) Packing Authorizations (§173.***)

(8A) Exceptions	n/a	see 49 CFR §173. n/a
(8B) Non-bulk	n/a	see 49 CFR §173. n/a
(8C) Bulk	n/a	see 49 CFR §173. n/a

(9) Quantity Limits

(9A) Passenger aircraft/rail	n/a
(9B) Cargo aircraft only	n/a

(10) Vessel stowage

(10A) Location	n/a see
(10B) Other	n/a

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.

This Hazmat is classified as "Forbidden". This means the material may not be offered for transportation or transported in the applicable mode of transport.