HazMat Tool — substance information

Cartridges, signal

HMT May 2026

UN / ID: UN 0312
Hazard class: 1.4G
Packing group: —
ERG guide: —
Special provisions: —
Source: 49 CFR §172 (2026/05)

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Cartridges, signal

Hazardous Materials Table

Source: 49 CFR §172 (2026/05)

(3) Hazard Class

1.4
Explosives

Compatibility group of explosives - Description of substances or article to be classified

Group: G

Pyrotechnic substance or article containing a pyrotechnic substance, or article containing both an explosive substance and an illuminating, incendiary, tear-producing or smoke-producing substance (other than a water-activated article or one containing white phosphorus, phosphide or flammable liquid or gel or hypergolic liquid).

Source: 49 CFR §173.52

Cargo Aircraft Only (Cargo Aircraft Only)

(7) Special Provisions (§172.102)

(8) Packing Authorizations (§173.***)

(8A) Exceptions	None
(8B) Non-bulk	62	see 49 CFR §173.62
(8C) Bulk	None

(9) Quantity Limits

(9A) Passenger aircraft/rail	Forbidden
(9B) Cargo aircraft only	75 kg

(10) Vessel stowage

(10A) Location

Stowage category “02” means the material may be stowed “on deck” in closed cargo transport units or “under deck” on a cargo vessel (up to 12 passengers) or “on deck” in closed cargo transport units or “under deck” in closed cargo transport units on a passenger vessel.

Source: 49 CFR §172.101(k)

(10B) Other

25	see 49 CFR §176.84

Source: 49 CFR §176.84

Segregation chart for load, transport, and storage

This chart shows whether loading, transport, or storage with other hazard classes is permitted, prohibited, or restricted. Based on 49 CFR §177.848.

Hazard class	8	7	6.1	5.2	5.1	4.3	4.2	4.1	3	2.3B	2.3A	2.2	2.1	1.6	1.5	1.4	1.3	1.1/1.2
1.1/1.2
1.3
1.4
1.5
1.6
2.1
2.2
2.3A
2.3B
3
4.1
4.2
4.3
5.1
5.2
6.1
7
8

	Must not be loaded, transported, or stored together in the same vehicle or facility.
	May be loaded, transported, or stored together.
	May be loaded, transported, or stored together only with restrictions.

Similar substances

UN / ID	Proper shipping name	Hazard class
UN 0492	Signals, railway track, explosive	1.3G
UN 0493	Signals, railway track, explosive	1.4G
UN 0193	Signals, railway track, explosive	1.4S
UN 0192	Signals, railway track, explosive	1.1G
UN 0505	Signals, distress, ship	1.4G
UN 0506	Signals, distress, ship	1.4S
UN 0194	Signals, distress, ship	1.1G
UN 0195	Signals, distress, ship	1.3G
UN 0373	Signal devices, hand	1.4S
UN 0191	Signal devices, hand	1.4G
UN 0196	Signals, smoke	1.1G
UN 0507	Signals, smoke	1.4S
UN 0487	Signals, smoke	1.3G
UN 0313	Signals, smoke	1.2G
UN 0197	Signals, smoke	1.4G