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(a) White square background. The following must have the specified placards placed on a white square background, as described in §172.527:
(1) Division 1.1 and 1.2 (explosive) materials which require EXPLOSIVES 1.1 or EXPLOSIVES 1.2 placards affixed to the rail car;
(2) Materials classed in Division 2.3 Hazard Zone A or 6.1 Packing Group I Hazard Zone A which require POISON GAS or POISON placards affixed to the rail car, including tank cars containing only a residue of the material; and
(3) Class DOT 113 tank cars used to transport a Division 2.1 (flammable gas) material, including tank cars containing only a residue of the material.
(b) Chemical ammunition. Each rail car containing Division 1.1 or 1.2 (explosive) ammunition which also meets the definition of a material poisonous by inhalation (see §171.8 of this subchapter) must be placarded EXPLOSIVES 1.1 or EXPLOSIVES 1.2 and POISON GAS or POISON INHALATION HAZARD.
[Amdt. 172–29, 41 FR 15996, Apr. 15, 1976, as amended by Amdt. 172–103, 51 FR 5971, Feb. 18, 1986; Amdt. 172–110, 52 FR 29528, Aug. 10, 1987; Amdt. 172–111, 52 FR 36671, Sept. 30, 1987; Amdt. 172–123, 55 FR 52601, Dec. 21, 1990; 56 FR 66260, Dec. 20, 1991; 57 FR 45460, Oct. 1, 1992; Amdt. 172–248, 61 FR 28676, June 5, 1996; Amdt. 172–151, 62 FR 1231, Jan. 8, 1997; 62 FR 39398, July 22, 1997]