(a) General. When Column 5 refers to a code for a hazardous material or PDM, the meaning of that code is set forth in this section.

(b) Table of Hazardous or Potentially Dangerous Characteristics.

Open Table
Code Hazardous or potentially dangerous characteristic
1 Contact with water may cause heating.
2 Contact with water may cause evolution of flammable gases, which may form explosive mixtures with air.
3 Contact with water may cause evolution of toxic gases.
4 If involved in a fire, will greatly intensify the burning of combustible materials.
5 A major fire aboard a vessel carrying this material may involve a risk of explosion in the event of contamination (e.g., by a fuel oil) or strong confinement. If heated strongly will decompose, giving off toxic gases that support combustion.
6 These mixtures may be subject to self-sustaining decomposition if heated. Decomposition, once initiated, may spread throughout the remainder, producing gases that are toxic.
7 Toxic if swallowed and by dust inhalation.
8 Harmful and irritating by dust inhalation.
9 Highly corrosive to steel.
10 Powerful allergen. Toxic by ingestion. Skin contact or inhalation of dust may cause severe irritation of skin, eyes, and mucous membranes in some people.
11 May be susceptible to spontaneous heating and ignition.
12 Liable to cause oxygen depletion in the cargo space.
13 Liable to emit methane gas which can form explosive mixtures with air.
14 Dust forms explosive mixtures with air.
15 May present substantial danger to the public health or welfare or the environment when released into the environment. Skin contact and dust inhalation should be avoided.
16 Combustible. Burns with dense black smoke. Dust may cause skin and eye irritation.
17 Radiation hazard from dust inhalation and contact with mucous membranes.
18 Susceptible to fire from sparks and open flames.
19 May self-heat slowly and, if wet or containing an excessive proportion of unoxidized oil, ignite spontaneously.
20 Fire may produce irritating or poisonous gases.
21 Dust may contain toxic constituents.
22 Lead nitrate and lead sulfide are hazardous substances; see code 15 of this table and §148.270.
23 Hazardous substance when consisting of pieces having a diameter less than 100 micrometers (0.004 in.); see code 15 of this table and §148.270.
24 Cargo subject to liquefaction.
25 Subject to liquefaction if average particle size of cargo is less than 10 mm (.394 in.).
26 This entry is considered a Marine Pollutant in accordance with 49 CFR 172.101 Appendix B.
27 This entry is considered a certain dangerous cargo in accordance with 33 CFR 160.202.

[75 FR 64591, Oct. 19, 2010, as amended by USCG-2005-21869, 80 FR 5336, Jan. 30, 2015]


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