UN/NA Number Reference
DOT Class 1.1A Explosive placard

UN 135: Mercury fulminate, wetted

49 CFR 172.101 Hazardous Materials Table·ERG 2024

DOT Classification and Shipping

UN 135 is assigned the proper shipping name Mercury fulminate, wetted in the U.S. DOT Hazardous Materials Table (49 CFR 172.101). It is classified as a Class 1.1A Explosive material. Required label(s): 1.1.

Packing group indicates the degree of danger within a hazard class: PG I is high danger, PG II medium, PG III low. The proper shipping name, hazard class, UN number, and packing group together form the basic shipping description that must appear on shipping papers and, where required, on the package and placard.

Emergency Response (ERG Guide 112)

Hazards: May explode or be projected if heated. Fragments may travel great distances. Fire may produce irritating or toxic gases.

Fire: DO NOT fight fire when it reaches cargo. Evacuate area and let burn. Fight fire from maximum distance.

Spill: Do not touch or walk through spilled material. Isolate spill area immediately.

Chemical and Physical Properties

Mercury fulminate, [wet] appears as a slurry or wet mass of white crystals. Contains at least 20% water or water-ethyl alcohol mixture. May explode from shock, heat, flame, or friction when dry. May explode under prolonged exposure to heat. Primary hazard is blast of an instantaneous explosion, not flying projectiles or fragments. A widely used initiating detonator for high explosives.

CAS Number: 628-86-4
Molecular Formula: C2HgN2O2
Molecular Weight: 284.63 g/mol
Color / Form: Grey, pale brown or white crystalline solid
Melting Point: Explodes
Specific Gravity: 4.42
Water Solubility: Soluble in alcohol, ammonium hydroxide, and hot water; slightly soluble in co...

Regulatory Data

CERCLA RQ (40 CFR 302.4)
10 lb
RCRA Waste Code(s)
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A release of this material at or above its CERCLA reportable quantity (10 lb) requires immediate notification to the National Response Center at 800-424-8802.

Special Provisions

49 CFR 172.102 special provision codes for this entry: 111, 117. These codes modify the general requirements (packaging, quantity limits, exceptions) for this specific material. Look up each code in 49 CFR 172.102 for the full text.

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Reference data compiled from the DOT Hazardous Materials Table (49 CFR 172.101), the 2024 Emergency Response Guidebook, and public chemical databases (PubChem, NIOSH, EPA). Always verify the correct shipping description against the current regulation and the manufacturer's SDS Section 14 before shipping.