HazMat Tool — substance information

Phosphorus white, molten

HMT 15 June 2026

UN / ID: UN 2447
Hazard class: 4.2
Packing group: I
ERG guide: ERG 136
Special provisions: SP B9, SP B26, SP N34, SP T21, SP TP3, SP TP7, SP TP26
Source: 49 CFR §172 (15 June 2026)

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Phosphorus white, molten

Phosphorus is a chemical element; it has symbol P and atomic number 15. All elemental forms of phosphorus are highly reactive and are therefore never found in nature. Elemental phosphorus can be prepared artificially, the two most common allotropes being white phosphorus and red phosphorus. With 31P as its only stable isotope, phosphorus has an occurrence in Earth's crust of about 0.1%, generally as phosphate rock Wikipedia

Substance Data

Source: PubChem (HSDB, 04.12.2019)

CAS-Number

7723-14-0

Flash Point

n/a

Boiling Point

n/a

Emergency Response Guide No. 136

Hazardous Materials Table

Source: 49 CFR §172 (15 June 2026)

(3) Hazard Class

4.2
Spontaneously combustible materials

(4) Identification number

UN 2447

(5) Packing Group

(6) Labels

Spontaneously combustible materials (4.2)

(7) Special Provisions (§172.102)

×Note:
Special provisions may be very complex. The extracts are taken from 49 CFR §172.102. Please be careful with the information, as necessary, additional conditions may be applied that are not written here. Please check the original source and report bugs.

Bottom outlets are not authorized.

Browse special provision B9

B26

Tanks must be insulated. Insulation must be at least 100 mm (3.9 inches) except that the insulation thickness may be reduced to 51 mm (2 inches) over the exterior heater coils. Interior heating coils are not authorized. The packaging may not be loaded with a material outside of the packaging's design temperature range. In addition, the material also must be covered with an inert gas or the container must be filled with water to the tank's capacity. After unloading, the residual material also must be covered with an inert gas or the container must be filled with water to the tank's capacity.

Browse special provision B26

N34

Aluminum construction materials are not authorized for any part of a packaging which is normally in contact with the hazardous material.

Browse special provision N34

T21

Minimum test pressure (bar)	10
Minimum shell thickness	10 mm
Pressure-relief requirements	Normal
Bottom opening requirements	Prohibited for liquids. § 178.275(d)(2).

Browse special provision T21

TP3

The maximum degree of filling (in %) for solids transported above their melting points and for elevated temperature liquids shall be determined by the following:
TP3

Where: d_f and d_r are the mean densities of the liquid at the mean temperature of the liquid during filling and the maximum mean bulk temperature during transport respectively.

Browse special provision TP3

TP7

The vapor space must be purged of air by nitrogen or other means.

Browse special provision TP7

TP26

The heating device must be exterior to the shell. For UN 3176, this requirement only applies when the hazardous material reacts dangerously with water.

Browse special provision TP26

(8) Packing Authorizations (§173.***)

(8A) Exceptions	None
(8B) Non-bulk	188	see 49 CFR §173.188
(8C) Bulk	243	see 49 CFR §173.243

(9) Quantity Limits

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

(10) Vessel stowage

(10A) Location	D Stowage category “D” means the material must be stowed “on deck only” on a cargo vessel or on a passenger vessel carrying a number of passengers limited to not more than the larger of 25 passengers or one passenger per each 3 m of overall vessel length, but the material is prohibited on a passenger vessel in which the limiting number of passengers is exceeded. Source: 49 CFR §172.101(k)
(10B) Other	n/a

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 1381	Phosphorus, white dry or Phosphorus, white, under water or Phosphorus white, in solution or Phosphorus, yellow dry or Phosphorus, yellow, under water or Phosphorus, yellow, in solution	4.2
NA 1955	Organic phosphate, mixed with compressed gas or Organic phosphate compound, mixed with compressed gas or Organic phosphorus compound, mixed with compressed gas	2.3
UN 3017	Organophosphorus pesticides, liquid, toxic, flammable, flash point not less than 23 degrees C	6.1
UN 0243	Ammunition, incendiary, white phosphorus, with burster, expelling charge or propelling charge	1.2H
UN 0244	Ammunition, incendiary, white phosphorus, with burster, expelling charge or propelling charge	1.3H
	Ammunition, smoke (water-activated contrivances), without white phosphorus or phosphides, with burster, expelling charge or propelling charge, see Contrivances, water-activated, etc. (UN 0249)
UN 2784	Organophosphorus pesticides, liquid, flammable, toxic, flash point less than 23 degrees C	3
UN 0245	Ammunition smoke, white phosphorus with burster, expelling charge, or propelling charge	1.2H
UN 0246	Ammunition, smoke, white phosphorus with burster, expelling charge, or propelling charge	1.3H
	Ammunition, smoke (water-activated contrivances), white phosphorus, with burster, expelling charge or propelling charge, see Contrivances, water-activated, etc. (UN 0248)
	Phosphorus (white or red) and a chlorate, mixtures of	Forbidden
UN 1339	Phosphorus heptasulfide, free from yellow or white phosphorus	4.1
UN 1340	Phosphorus pentasulfide, free from yellow or white phosphorus	4.3
UN 1341	Phosphorus sesquisulfide, free from yellow or white phosphorus	4.1
UN 1343	Phosphorus trisulfide, free from yellow or white phosphorus	4.1