Potassium

Potassium is a chemical element; it has symbol K (from Neo-Latin kalium) and atomic number 19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives. Wikipedia

Substance Data

Source: TOXNET

CAS-Number

7440-09-7

Flash Point

n/a

Boiling Point

n/a

Emergency Response Guide No. 138

Data from the Hazardous Materials Table

Source: 49 CFR §172 (2018/07)

(3) Hazard Class

4.3
Dangerous when wet materials

(4) Identification number

UN 2257

(5) Packing Group

(6) Labels

Cargo Aircraft Only (Cargo Aircraft Only)

(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.

A7	Steel packagings must be corrosion-resistant or have protection against corrosion. Browse special provision A7
A19	Combination packagings consisting of outer fiber drums or plywood drums, with inner plastic packagings, are not authorized for transportation by aircraft. Browse special provision A19
A20	Plastic bags as inner receptacles of combination packagings are not authorized for transportation by aircraft. Browse special provision A20
B27	Tanks must have a service pressure of 1,034 kPa (150 psig). Tank car tanks must have a test pressure rating of 1,379 kPa (200 psig). Lading must be blanketed at all times with a dry inert gas at a pressure not to exceed 103 kPa (15 psig). Browse special provision B27
IB4	Authorized IBCs: Metal (11A, 11B, 11N, 21A, 21B, 21N, 31A, 31B and 31N). Browse special provision IB4
IP1	IBCs must be packed in closed freight containers or a closed transport vehicle. Browse special provision IP1
N6	Battery fluid packaged with electric storage batteries, wet or dry, must conform to the packaging provisions of §173.159 (g) or (h) of this subchapter. Browse special provision N6
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
T9	see 49 CFR §172.102
TP7	The vapor space must be purged of air by nitrogen or other means. Browse special provision TP7
TP33	The portable tank instruction assigned for this substance applies for granular and powdered solids and for solids which are filled and discharged at temperatures above their melting point which are cooled and transported as a solid mass. Solid substances transported or offered for transport above their melting point are authorized for transportation in portable tanks conforming to the provisions of portable tank instruction T4 for solid substances of packing group III or T7 for solid substances of packing group II, unless a tank with more stringent requirements for minimum shell thickness, maximum allowable working pressure, pressure-relief devices or bottom outlets are assigned in which case the more stringent tank instruction and special provisions shall apply. Filling limits must be in accordance with portable tank special provision TP3. Solids meeting the definition of an elevated temperature material must be transported in accordance with the applicable requirements of this subchapter. Browse special provision TP33
W32	see 49 CFR §172.102

(8) Packing Authorizations (§173.***)

(8A) Exceptions	151	see 49 CFR §173.151
(8B) Non-bulk	211	see 49 CFR §173.211
(8C) Bulk	244	see 49 CFR §173.244

(9) Quantity Limits

(9A) Passenger aircraft/rail	Forbidden
(9B) Cargo aircraft only	15 kg

(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

13	Keep as dry as reasonably practicable.
52	Stow “separated from” acids.¹ ²
148	see 49 CFR §176.84

¹For waste cyanides or waste cyanide mixtures or solutions, refer to §173.12(e) of this subchapter.

² Class 8 materials in PG II or III that otherwise are required to be segregated from one another may be transported in the same cargo transport unit, whether in the same packaging or not, provided the substances do not react dangerously with each other to cause combustion and/or evolution of considerable heat, or of flammable, toxic or asphyxiant gases, or the formation of corrosive or unstable substances; and the package does not contain more than 30 L (7.8 gallons) for liquids or 30 kg (66 lbs.) for solids.

Source: 49 CFR §176.84

Segregation Chart for Load, Transport, Storage

In this table a statement is contained for each hazard class whether the loading, transport or storage with other hazard classes is allowed, is not permitted or is restricted. The table is based on U.S.-Code 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

	May not be loaded, transported, or stored together in the same transport vehicle or storage facility.
	Load, transport, storage together is not restricted.
	Load, transport, storage together is allowed under restrictions.

Substances with similar name

UN-Number	Name	Hazard Class
	Chlorate of potash, see Potassium chlorate
UN 1626	Mercuric potassium cyanide	6.1
UN 1643	Mercury potassium iodide	6.1
UN 2257	Potassium	4.3
UN 1677	Potassium arsenate	6.1
	Potassium bisulfite solution, see Bisulfites, aqueous solutions, n.o.s.
UN 1870	Potassium borohydride	4.3
UN 1484	Potassium bromate	5.1
UN 2427	Potassium chlorate, aqueous solution	5.1
UN 1679	Potassium cuprocyanide	6.1
UN 1929	Potassium dithionite or Potassium hydrosulfite	4.2
UN 1812	Potassium fluoride, solid	6.1
UN 3422	Potassium fluoride solution	6.1
UN 2628	Potassium fluoroacetate	6.1
UN 1811	Potassium hydrogendifluoride solid	8
UN 3421	Potassium hydrogendifluoride solution	8
	Potassium hydrosulfite, see Potassium dithionite
UN 1814	Potassium hydroxide, solution	8
UN 1487	Potassium nitrate and sodium nitrite mixtures	5.1
UN 1492	Potassium persulfate	5.1
UN 2012	Potassium phosphide	4.3
UN 1422	Potassium sodium alloys, liquid	4.3
UN 3404	Potassium sodium alloys, solid	4.3
UN 1382	Potassium sulfide, anhydrous or Potassium sulfide with less than 30 percent water of crystallization	4.2
UN 1847	Potassium sulfide, hydrated with not less than 30 percent water of crystallization	8