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Phosphorus oxychloride

HMT 15 June 2026

UN / ID: UN 1810
Hazard class: 6.1
Packing group: I
ERG guide: ERG 137
Special provisions: SP 2, SP B9, SP B14, SP B32, SP B77, SP N34, SP T20, SP TP2, more…
Source: 49 CFR §172 (15 June 2026)

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Phosphorus oxychloride

Phosphoryl chloride (commonly called phosphorus oxychloride) is a colourless liquid with the formula POCl3. It hydrolyses in moist air releasing phosphoric acid and fumes of hydrogen chloride. It is manufactured industrially on a large scale from phosphorus trichloride and oxygen or phosphorus pentoxide. It is mainly used to make phosphate esters Wikipedia

Substance Data

Source: PubChem (HSDB, 22.10.2026)

CAS-Number

10025-87-3

Flash Point

—

Boiling Point

105.8 ° C

Emergency Response Guide No. 137

Hazardous Materials Table

Source: 49 CFR §172 (15 June 2026)

(3) Hazard class

6.1
Poisonous Material

(4) Identification number

UN 1810

(5) Packing Group

(6) Labels

(1) Symbols

This entry is signed with plus (+). The plus (+) sign fixes the proper shipping name, hazard class and packing group for that entry without regard to whether the material meets the definition of that class, packing group or any other hazard class definition. When the plus sign is assigned, it means that the material is known to pose a risk to humans. When a plus sign is assigned to mixtures or solutions containing a material where the hazard to humans is significantly different from that of the pure material or where no hazard to humans is posed, the material may be described using an alternative shipping name that represents the hazards posed by the material. An appropriate alternate proper shipping name and hazard class may be authorized by the Associate Administrator.

(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.

This material is poisonous by inhalation (see § 171.8 of this subchapter) in Hazard Zone B (see § 173.116(a) or § 173.133(a) of this subchapter), and must be described as an inhalation hazard under the provisions of this subchapter.

Browse special provision 2

Bottom outlets are not authorized.

Browse special provision B9

B14

Each bulk packaging, except a tank car or a multi-unit-tank car tank, must be insulated with an insulating material so that the overall thermal conductance at 15.5 °C (60 °F) is no more than 1.5333 kilojoules per hour per square meter per degree Celsius (0.075 Btu per hour per square foot per degree Fahrenheit) temperature differential. Insulating materials must not promote corrosion to steel when wet.

Browse special provision B14

B32

MC 312, MC 330, MC 331, DOT 412 cargo tanks and DOT 51 portable tanks must be made of stainless steel, except that steel other than stainless steel may be used in accordance with the provisions of § 173.24b(b) of this subchapter. Thickness of stainless steel for tank shell and heads for cargo tanks and portable tanks must be the greater of 6.35 mm (0.250 inch) or the thickness required for a tank with a design pressure at least equal to 1.3 times the vapor pressure of the lading at 46 °C (115 °F). In addition, MC 312 and DOT 412 cargo tank motor vehicles must:
a. Be ASME Code (U) stamped for 100% radiography of all pressure-retaining welds;
b. Have accident damage protection which conforms with § 178.345-8 of this subchapter;
c. Have a MAWP or design pressure of at least 87 psig; and
d. Have a bolted manway cover.

Browse special provision B32

B77

Other packaging are authorized when approved by the Associate Administrator.

Browse special provision B77

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

T20

Minimum test pressure (bar)	10
Minimum shell thickness	8 mm
Pressure-relief requirements	§ 178.275(g)(3)
Bottom opening requirements	Prohibited

Browse special provision T20

TP2

a. The maximum degree of filling must not exceed the degree of filling determined by the following:
TP2a

Where:
t_r is the maximum mean bulk temperature during transport,
t_f is the temperature in degrees celsius of the liquid during filling, and
α is the mean coefficient of cubical expansion of the liquid between the mean temperature of the liquid during filling (t_f) and the maximum mean bulk temperature during transportation (t_r) both in degrees celsius.
b. For liquids transported under ambient conditions α may be calculated using the formula:
TP2b

Where:
d₁₅ and d₅₀ are the densities (in units of mass per unit volume) of the liquid at 15 °C (59 °F) and 50 °C (122 °F), respectively.

Browse special provision TP2

TP13

Self-contained breathing apparatus must be provided when this hazardous material is transported by sea.

Browse special provision TP13

TP38

Each portable tank must be insulated with an insulating material so that the overall thermal conductance at 15.5 °C (60 °F) is no more than 1.5333 kilojoules per hour per square meter per degree Celsius (0.075 Btu per hour per square foot per degree Fahrenheit) temperature differential. Insulating materials may not promote corrosion to steel when wet.

Browse special provision TP38

TP45

Each portable tank must be made of stainless steel, except that steel other than stainless steel may be used in accordance with the provisions of 173.24b(b) of this subchapter. Thickness of stainless steel for portable tank shells and heads must be the greater of 6.35 mm (0.250 inch) or the thickness required for a portable tank with a design pressure at least equal to 1.3 times the vapor pressure of the hazardous material at 46 °C (115 °F).

Browse special provision TP45

(8) Packing Authorizations (§173.***)

(8A) Exceptions	None
(8B) Non-bulk	227	see 49 CFR §173.227
(8C) Bulk	244	see 49 CFR §173.244

(9) Quantity Limits

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

(10) Vessel stowage

(10A) Location

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

40	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.

Hinweis: In der Kompatibilitätstabelle sind Stoffe der Gefahrenklasse 6.1 nur dann gesondert zu berücksichtigen, wenn der Stoff als inhalativ giftig (Gefahrenzone A) sowie in der Verpackungsgruppe I eingestuft ist. Siehe Sonderbestimmung 1 sowie PHMSA Interpretation #09-0252.

Packages with POISON or POISON INHALATION HAZARD labels, or a POISON label displaying “PG III,” or “PG III” marked next to a POISON label may not be transported with foodstuffs, feed or any other edible material, intended for humans or animals. For exceptions see 49 CFR §177.841(e).

Scope & sources (important)Click to show CFR references

This check evaluates segregation per 49 CFR §177.848. Additional loading/unloading and handling requirements may still apply; see 49 CFR §177 Subpart B (Loading and Unloading):

§177.834 - General requirements
§177.835 - Class 1 materials
§177.837 - Class 3 materials
§177.838 - Class 4 (flammable solid) materials, Class 5 (oxidizing) materials, and Division 4.2 (pyroforic liquid) materials
§177.839 - Class 8 (corrosive) materials
§177.840 - Class 2 (gases) materials
§177.841 - Division 6.1 and Division 2.3 materials
§177.842 - Class 7 (radioactive) material
§177.843 - Contamination of vehicles

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 2784	Organophosphorus pesticides, liquid, flammable, toxic, flash point less than 23 degrees C	3
UN 0244	Ammunition, incendiary, white phosphorus, with burster, expelling charge or propelling charge	1.3H
UN 0243	Ammunition, incendiary, white phosphorus, with burster, expelling charge or propelling charge	1.2H
	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 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