HazMat Tool — substance information

Isocyanates, flammable, toxic, n.o.s. or Isocyanate solutions, flammable, toxic, n.o.s. flash point less than 23 degrees C

HMT May 2026

UN / ID: UN 2478
Hazard class: 3
Packing group: II (multiple — see tabs)
ERG guide: ERG 155
Special provisions: SP 5, SP A3, SP A7, SP IB2, SP T11, SP TP2, SP TP13, SP TP27, more…
Source: 49 CFR §172 (2026/05)

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Isocyanates, flammable, toxic, n.o.s. or Isocyanate solutions, flammable, toxic, n.o.s. flash point less than 23 degrees C

Emergency Response Guide No. 155

Hazardous Materials Table

Source: 49 CFR §172 (2026/05)

Packing group II
Packing group III

(3) Hazard Class

3
Flammable liquids

This entry is signed with "G". The letter "G" identifies proper shipping names for which one or more technical names of the hazardous material must be entered in parentheses, in association with the basic description. (See §172.203(k)).

(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.

If this material meets the definition for a material poisonous by inhalation (see §171.8), a shipping name must be selected which identifies the inhalation hazard, in Division 2.3 or Division 6.1, as appropriate.

Browse special provision 5

For combination packagings, if glass inner packagings (including ampoules) are used, they must be packed with absorbent material in tightly closed rigid and leakproof receptacles before packing in outer packagings.

Browse special provision A3

Steel packagings must be corrosion-resistant or have protection against corrosion.

Browse special provision A7

IB2

Authorized IBCs: Metal (31A, 31B and 31N); Rigid plastics (31H1 and 31H2); Composite (31HZ1).
Additional Requirement: Only liquids with a vapor pressure less than or equal to 110 kPa at 50 °C (1.1 bar at 122 °F), or 130 kPa at 55 °C (1.3 bar at 131 °F) are authorized.

Browse special provision IB2

T11

Minimum test pressure (bar)	6
Minimum shell thickness	§ 178.274(d)(2)
Pressure-relief requirements	Normal
Bottom opening requirements	§ 178.275(d)(3)

Browse special provision T11

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

TP27

A portable tank having a minimum test pressure of 4 bar (400 kPa) may be used provided the calculated test pressure is 4 bar or less based on the MAWP of the hazardous material, as defined in §178.275, where the test pressure is 1.5 times the MAWP.

Browse special provision TP27

W31

Non-bulk packagings must be hermetically sealed.

Browse special provision W31

(8) Packing Authorizations (§173.***)

(8A) Exceptions	150	see 49 CFR §173.150
(8B) Non-bulk	202	see 49 CFR §173.202
(8C) Bulk	243	see 49 CFR §173.243

(9) Quantity Limits

(9A) Passenger aircraft/rail	1 L
(9B) Cargo aircraft only	60 L

(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

(3) Hazard Class

3
Flammable liquids

(4) Identification number

UN 2478

(5) Packing Group

III

Comparison View of PG

(6) Labels

(1) Symbols

(7) Special Provisions (§172.102)

Browse special provision 5

Browse special provision A3

Steel packagings must be corrosion-resistant or have protection against corrosion.

Browse special provision A7

IB3

Authorized IBCs: Metal (31A, 31B and 31N); Rigid plastics (31H1 and 31H2); Composite (31HZ1 and 31HA2, 31HB2, 31HN2, 31HD2 and 31HH2).
Additional Requirement: Only liquids with a vapor pressure less than or equal to 110 kPa at 50 °C (1.1 bar at 122 °F), or 130 kPa at 55 °C (1.3 bar at 131 °F) are authorized, except for UN2672 (also see special provision IP8 in Table 2 for UN2672).

Browse special provision IB3

Minimum test pressure (bar)	4
Minimum shell thickness	§ 178.274(d)(2)
Pressure-relief requirements	Normal
Bottom opening requirements	§ 178.275(d)(3)

Browse special provision T7

TP1

The maximum degree of filling must not exceed the degree of filling determined by the following:
TP1

Where:
t_r is the maximum mean bulk temperature during transport, and t_f is the temperature in degrees celsius of the liquid during filling.

Browse special provision TP1

TP13

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

Browse special provision TP13

TP28

A portable tank having a minimum test pressure of 2.65 bar (265 kPa) may be used provided the calculated test pressure is 2.65 bar or less based on the MAWP of the hazardous material, as defined in §178.275, where the test pressure is 1.5 times the MAWP.

Browse special provision TP28

W31

Non-bulk packagings must be hermetically sealed.

Browse special provision W31

(8) Packing Authorizations (§173.***)

(8A) Exceptions	150	see 49 CFR §173.150
(8B) Non-bulk	203	see 49 CFR §173.203
(8C) Bulk	242	see 49 CFR §173.242

(9) Quantity Limits

(9A) Passenger aircraft/rail	60 L
(9B) Cargo aircraft only	220 L

(10) Vessel stowage

(10A) Location	A Stowage category “A” means the material may be stowed “on deck” or “under deck” on a cargo vessel or on a passenger vessel. Source: 49 CFR §172.101(k)
(10B) Other	n/a

Packing group comparison

Multiple packing groups apply to this entry. See assignment criteria in 49 CFR §173 Subpart D. Details are in the tabs above; differences are highlighted.

	PG II	PG III
1	G	G
2	Isocyanates, flammable, toxic, n.o.s. or Isocyanate solutions, flammable, toxic, n.o.s. flash point less than 23 degrees C	Isocyanates, flammable, toxic, n.o.s. or Isocyanate solutions, flammable, toxic, n.o.s. flash point less than 23 degrees C
3	3	3
4	UN 2478	UN 2478
5	II	III
6	3, 6.1	3, 6.1
7	5, A3, A7, IB2, T11, TP2, TP13, TP27, W31	5, A3, A7, IB3, T7, TP1, TP13, TP28, W31
8A	150	150
8B	202	203
8C	243	242
9A	1 L	60 L
9B	60 L	220 L
10A	D	A
10B	40	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 3080	Isocyanates, toxic, flammable, n.o.s. or Isocyanate solutions, toxic, flammable, n.o.s., flash point not less than 23 degrees C but not more than 61 degrees C and boiling point less than 300 degrees C	6.1
UN 2206	Isocyanates, toxic, n.o.s. or Isocyanate solutions, toxic, n.o.s., flash point more than 61 degrees C and boiling point less than 300 degrees C	6.1
UN 2250	Dichlorophenyl isocyanates	6.1
UN 2236	3-Chloro-4-methylphenyl isocyanate, liquid	6.1
UN 3428	3-Chloro-4-methylphenyl isocyanate, solid	6.1
UN 2281	Hexamethylene diisocyanate	6.1
UN 2290	Isophorone diisocyanate	6.1
UN 2078	Toluene diisocyanate	6.1
UN 2328	Trimethylhexamethylene diisocyanate	6.1
UN 2488	Cyclohexyl isocyanate	6.1
UN 2481	Ethyl isocyanate	6.1
UN 2486	Isobutyl isocyanate	6.1
UN 2483	Isopropyl isocyanate	6.1
UN 2605	Methoxymethyl isocyanate	6.1
UN 2480	Methyl isocyanate	6.1