A separate additional placard is required for materials that _________.

If the words POISON INHALATION or TOXIC INHALATION HAZARD appear on the shipping paper, package or label, the rules require that the transport vehicle be placarded with a POISON INHALATION HAZARD or POISON GAS placard, as appropriate.
These placards must be used in addition to other placards that may be required by the product's hazard class. INHALATION HAZARD materials always require the appropriate placard, even for small amounts of these materials.