Ignition Temperatures and Pyrophoricity of Plutonium, Its Alloys, and Its Compounds

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

Table 2.9. (continued)

Sodium nitrite

7632-00-0

NaNO2

CAS No.(b)

Chemical Name

Hazard

Formula

Stannous chloride

7772-99-8

SnCl2

Sulfamic acid

5329-14-6

Corrosive

NH2SO3H

Sulfuric acid

7664-93-9

Corrosive, poison

H2SO4

Tri-n-butyl phosphate

126-73-8

Flammable liquid

(C4H7O)3PO4

Urea

57-13-6

CO(NH2)2

Uranium (metal)

Flammable

Zinc chloride

7646-85-7

ZnCl2

Soltrol 170 Phillips 66

68551-19-9

Flammable liquid

(Mixture C10C14

isoparafins)

Carbon tetrafluoride

75-73-0

CF4

(a) Refer to Material Safety Data Sheets for complete discussion of hazards.

(b) Chemical Abstracts Service Registry number.

The corrosion or oxidation of plutonium does not always occur in a linear or

predictable manner. The oxidation rate is a complex function of the surrounding

atmosphere, the moisture content, and the alloys or impurities present in the

metallic plutonium.4

2.6.3.2 Ignition Temperatures and Pyrophoricity of Plutonium, Its Alloys, and Its

Compounds

Plutonium and some of its alloys and compounds are pyrophoric. Pyrophoric

material is a liquid or solid that, even in small quantities and without an external

ignition source, can ignite within 5 minutes after coming in contact with air

(NFPA Fire Protection Handbook). Pyrophoric plutonium metal has been

defined as "that metal which will ignite spontaneously in air at a temperature of

150C (320F) or below in the absence of external heat, shock, or friction"

(Stakebake, 1992).5 Finely divided plutonium metal would be considered

pyrophoric while massive plutonium would be nonpyrophoric. Martz et al.

See Wick (1967), Coffinberry and Miner (1961), and Kay and Waldron (1966) for details on the oxidation of unalloyed plutonium and the

stabilized alloy of plutonium.

Also in DOE/DP-0123T, Assessment of Plutonium Storage Safety Issues at Department of Energy Facilities (DOE, 1994a).

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