HazMat Tool — substance information

Hydrofluoric acid, with more than 60 percent strength

HMT May 2026

UN / ID: UN 1790
Hazard class: 8
Packing group: I (multiple — see tabs)
ERG guide: ERG 157
Special provisions: SP A7, SP B4, SP B15, SP B23, SP N5, SP N34, SP T10, SP TP2, more…
Source: 49 CFR §172 (2026/05)

On this page

Hydrofluoric acid, with more than 60 percent strength

Hydrofluoric acid is a solution of hydrogen fluoride (HF) in water. Solutions of HF are colorless, acidic and highly corrosive. A common concentration is 49% (48–52%) but there are also stronger solutions (e.g. 70%) and pure HF has a boiling point near room temperature. Wikipedia

Substance Data

Source: PubChem (HSDB, 04.12.2019)

CAS-Number

7664-39-3

Flash Point

n/a

Boiling Point

n/a

Emergency Response Guide No. 157

Hazardous Materials Table

Source: 49 CFR §172 (2026/05)

Packing group I
Packing group II

(3) Hazard Class

8
Corrosive liquids

(4) Identification number

UN 1790

(5) Packing Group

Comparison View of PG

(6) Labels

(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.

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

Browse special provision A7

MC 300, MC 301, MC 302, MC 303, MC 305, and MC 306 and DOT 406 cargo tanks are not authorized.

Browse special provision B4

B15

Packagings must be protected with non-metallic linings impervious to the lading or have a suitable corrosion allowance.

Browse special provision B15

B23

Tanks must be made of steel that is rubber lined or unlined. Unlined tanks must be passivated before being placed in service. If unlined tanks are washed out with water, they must be repassivated prior to return to service. Lading in unlined tanks must be inhibited so that the corrosive effect on steel is not greater than that of hydrofluoric acid of 65 percent concentration.

Browse special provision B23

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

Browse special provision N5

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

T10

Minimum test pressure (bar)	4
Minimum shell thickness	6 mm
Pressure-relief requirements	§ 178.275(g)(3)
Bottom opening requirements	Prohibited

Browse special provision T10

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

(8) Packing Authorizations (§173.***)

(8A) Exceptions	None
(8B) Non-bulk	201	see 49 CFR §173.201
(8C) Bulk	243	see 49 CFR §173.243

(9) Quantity Limits

(9A) Passenger aircraft/rail	0.5 L
(9B) Cargo aircraft only	2.5 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

12	see 49 CFR §176.84
25	see 49 CFR §176.84
40	see 49 CFR §176.84
53	see 49 CFR §176.84
58	see 49 CFR §176.84

Source: 49 CFR §176.84

(3) Hazard Class

8
Corrosive liquids

(4) Identification number

UN 1790

(5) Packing Group

Comparison View of PG

(6) Labels

(7) Special Provisions (§172.102)

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

Browse special provision A7

B15

Packagings must be protected with non-metallic linings impervious to the lading or have a suitable corrosion allowance.

Browse special provision B15

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

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

Browse special provision N5

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

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

Browse special provision T8

TP2

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

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

(8) Packing Authorizations (§173.***)

(8A) Exceptions	154	see 49 CFR §173.154
(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	30 L

(10) Vessel stowage

(10A) Location

Source: 49 CFR §172.101(k)

(10B) Other

12	see 49 CFR §176.84
25	see 49 CFR §176.84
40	see 49 CFR §176.84
53	see 49 CFR §176.84
58	see 49 CFR §176.84

Source: 49 CFR §176.84

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 I	PG II
1
2	Hydrofluoric acid, with more than 60 percent strength	Hydrofluoric acid, with not more than 60 percent strength
3	8	8
4	UN 1790	UN 1790
5	I	II
6	8, 6.1	8, 6.1
7	A7, B4, B15, B23, N5, N34, T10, TP2, TP13	A7, B15, IB2, N5, N34, T8, TP2
8A	None	154
8B	201	202
8C	243	243
9A	0.5 L	1 L
9B	2.5 L	30 L
10A	D	D
10B	12, 25, 40, 53, 58	12, 25, 40, 53, 58

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.

Note: In this segregation and separation chart are HazMat of hazard class 8 considered depending if there are liquid. Currently HazMat Tool is not able to to check if a HazMat is liquid or not. Therefore it is assumed as liquid. See PHMSA Interpretation #09-0252.

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 1786	Hydrofluoric acid and Sulfuric acid mixtures	8
UN 1790	Hydrofluoric acid, with more than 60 percent strength	8
	Sulfuric and hydrofluoric acid mixtures, see Hydrofluoric and sulfuric acid mixtures