DOT Hazard Class

Class 8

Corrosive

49 CFR §173.136

Placard: White-top / black-bottom placard with hand and metal being corroded

ERG entries

Divisions

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Packing groups

I · II · III

Compat groups

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Definition

A liquid or solid that causes full-thickness destruction of human skin at the site of contact within a specified period of time, OR a liquid that has a severe corrosion rate on steel or aluminum surfaces exceeding 6.25 mm/year at a test temperature of 55 °C (130 °F).

Primary hazards

Highly corrosive — will burn skin, eyes, and mucous membranes
Reaction with metals may produce flammable hydrogen gas
Some react violently with water — heat and spatter
Vapors may be toxic and/or corrosive to airways

Public safety response

Isolate spill or leak area for at least 50 m (150 ft) for liquids and 25 m (75 ft) for solids. Ventilate closed spaces. Do not touch or walk through spilled material. Use full PPE including face shield.

Common materials in this class

Sulfuric acid, hydrochloric (muriatic) acid, nitric acid, sodium hydroxide (caustic soda / lye), potassium hydroxide, ammonium hydroxide, bleach, battery fluid.

UN1789Hydrochloric acid UN1830Sulfuric acid, more than 51%UN1789Muriatic acid UN1824Sodium hydroxide solution UN1791Hypochlorite solution

Packing groups

I: Great danger — full-thickness destruction of intact skin within an observation period of ≤ 3 minutes after exposure ≤ 60 minutes
II: Medium danger — full-thickness destruction after exposure of > 3 min but ≤ 60 min with observation period ≤ 14 days
III: Minor danger — full-thickness destruction after exposure > 60 min but ≤ 4 hr, OR does not cause full-thickness destruction but has a corrosion rate on steel or aluminum > 6.25 mm/year at 55 °C

Special provisions / notes

Some Class 8 materials are also oxidizers (nitric acid, chromic acid) or toxic (bromine, hydrofluoric acid) — subsidiary hazards drive additional placards. Fuming acids in bulk require CORROSIVE placard plus subsidiary.

Definition

Primary hazards

Highly corrosive — will burn skin, eyes, and mucous membranes
Reaction with metals may produce flammable hydrogen gas
Some react violently with water — heat and spatter
Vapors may be toxic and/or corrosive to airways

Public safety response

Common materials in this class

Sulfuric acid, hydrochloric (muriatic) acid, nitric acid, sodium hydroxide (caustic soda / lye), potassium hydroxide, ammonium hydroxide, bleach, battery fluid.

UN1789Hydrochloric acid UN1830Sulfuric acid, more than 51%UN1789Muriatic acid UN1824Sodium hydroxide solution UN1791Hypochlorite solution

Packing groups

I: Great danger — full-thickness destruction of intact skin within an observation period of ≤ 3 minutes after exposure ≤ 60 minutes
II: Medium danger — full-thickness destruction after exposure of > 3 min but ≤ 60 min with observation period ≤ 14 days
III: Minor danger — full-thickness destruction after exposure > 60 min but ≤ 4 hr, OR does not cause full-thickness destruction but has a corrosion rate on steel or aluminum > 6.25 mm/year at 55 °C