[Code of Federal Regulations]
[Title 49, Volume 2]
[Revised as of October 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR173.120]

[Page 476-477]
 
                        TITLE 49--TRANSPORTATION
 
 CHAPTER I--RESEARCH AND SPECIAL PROGRAMS ADMINISTRATION, DEPARTMENT OF 
                             TRANSPORTATION
 
PART 173--SHIPPERS--GENERAL REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS--Table of Contents
 
  Subpart D--Definitions Classification, Packing Group Assignments and 
    Exceptions for Hazardous Materials Other Than Class 1 and Class 7
 
Sec. 173.120  Class 3--Definitions.

    (a) Flammable liquid. For the purpose of this subchapter, a 
flammable liquid (Class 3) means a liquid having a flash point of not 
more than 60.5  deg.C (141  deg.F), or any material in a liquid phase 
with a flash point at or above 37.8  deg.C (100  deg.F) that is 
intentionally heated and offered for transportation or transported at or 
above its flash point in a bulk packaging, with the following 
exceptions:
    (1) Any liquid meeting one of the definitions specified in 
Sec. 173.115.
    (2) Any mixture having one or more components with a flash point of 
60.5  deg.C (141  deg.F) or higher, that make up at least 99 percent of 
the total volume of the mixture, if the mixture is not offered for 
transportation or transported at or above its flash point.
    (3) Any liquid with a flash point greater than 35  deg.C (95  deg.F) 
which does not sustain combustion according to ASTM 4206 or the 
procedure in appendix H of this part.
    (4) Any liquid with a flash point greater than 35  deg.C (95  deg.F) 
and with a fire point greater than 100  deg.C (212  deg.F) according to 
ISO 2592.
    (5) Any liquid with a flash point greater than 35  deg.C (95  deg.F) 
which is in a water-miscible solution with a water content of more than 
90 percent by mass.
    (b) Combustible liquid. (1) For the purpose of this subchapter, a 
combustible liquid means any liquid that does not meet the definition of 
any other hazard class specified in this subchapter and has a flash 
point above 60.5  deg.C (141  deg.F) and below 93  deg.C (200  deg.F).
    (2) A flammable liquid with a flash point at or above 38  deg.C (100 
 deg.F) that does not meet the definition of any other hazard class may 
be reclassed as a combustible liquid. This provision does not apply to 
transportation by vessel or aircraft, except where other means of 
transportation is impracticable. An elevated temperature material that 
meets the definition of a Class 3 material because it is intentionally 
heated and offered for transportation or transported at or above its 
flash point may not be reclassed as a combustible liquid.

[[Page 477]]

    (3) A combustible liquid which does not sustain combustion is not 
subject to the requirements of this subchapter as a combustible liquid. 
Either the test method specified in ASTM 4206 or the procedure in 
appendix H of this part may be used to determine if a material sustains 
combustion when heated under test conditions and exposed to an external 
source of flame.
    (c) Flash point. (1) Flash point means the minimum temperature at 
which a liquid gives off vapor within a test vessel in sufficient 
concentration to form an ignitable mixture with air near the surface of 
the liquid. It shall be determined as follows:
    (i) For a homogeneous, single-phase, liquid having a viscosity less 
than 45 S.U.S. at 38  deg.C (100  deg.F) that does not form a surface 
film while under test, one of the following test procedures shall be 
used:
    (A) Standard Method of Test for Flash Point by Tag Closed Tester, 
(ASTM D 56);
    (B) Standard Methods of Test for Flash Point of Liquids by Setaflash 
Closed Tester, (ASTM D 3278); or
    (C) Standard Test Methods for Flash Point by Small Scale Closed 
Tester, (ASTM D 3828).
    (ii) For a liquid other than one meeting all of the criteria of 
paragraph (c)(1)(i) of this section, one of the following test 
procedures shall be used:
    (A) Standard Method of Test for Flash Point by Pensky--Martens 
Closed Tester, (ASTM D 93). For cutback asphalt, use Method B of ASTM D 
93 or alternate tests authorized in this standard; or
    (B) Standard Methods of Test for Flash Point of Liquids by Setaflash 
Closed Tester (ASTM D 3278).
    (2) For a liquid that is a mixture of compounds that have different 
volatility and flash points, its flash point shall be determined as 
specified in paragraph (c)(1) of this section, on the material in the 
form in which it is to be shipped. If it is determined by this test that 
the flash point is higher than -7  deg.C (20  deg.F) a second test shall 
be made as follows: a portion of the mixture shall be placed in an open 
beaker (or similar container) of such dimensions that the height of the 
liquid can be adjusted so that the ratio of the volume of the liquid to 
the exposed surface area is 6 to one. The liquid shall be allowed to 
evaporate under ambient pressure and temperature (20 to 25  deg.C (68 to 
77  deg.F)) for a period of 4 hours or until 10 percent by volume has 
evaporated, whichever comes first. A flash point is then run on a 
portion of the liquid remaining in the evaporation container and the 
lower of the two flash points shall be the flash point of the material.
    (3) For flash point determinations by Setaflash closed tester, the 
glass syringe specified need not be used as the method of measurement of 
the test sample if a minimum quantity of 2 mL (0.1 ounce) is assured in 
the test cup.
    (d) If experience or other data indicate that the hazard of a 
material is greater or less than indicated by the criteria specified in 
paragraphs (a) and (b) of this section, the Associate Administrator may 
revise the classification or make the material subject or not subject to 
the requirements of parts 170-189 of this subchapter.

[Amdt. 173-224, 55 FR 52634 Dec. 21, 1990, as amended by Amdt. 173-227, 
56 FR 49989, Oct. 2, 1991; 56 FR 66268, Dec. 20, 1991; 57 FR 45461, Oct. 
1, 1992; Amdt. 173-241, 59 FR 67506, 67507, Dec. 29, 1994; Amdt. 173-
255, 61 FR 50625, Sept. 26, 1996; Amdt. 173-261, 62 FR 24731, May 6, 
1997; 66 FR 45379, 45381, Aug. 28, 2001]