# 148.11 Hazardous or potentially dangerous characteristics.
(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.
| 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 ( 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]