[Code of Federal Regulations]
[Title 27, Volume 1]
[Revised as of April 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 27CFR30.25]

[Page 718]
 
            TITLE 27--ALCOHOL, TOBACCO PRODUCTS AND FIREARMS
 
 CHAPTER I--BUREAU OF ALCOHOL, TOBACCO AND FIREARMS, DEPARTMENT OF THE 
                                TREASURY
 
PART 30--GAUGING MANUAL--Table of Contents
 
                     Subpart C--Gauging Instruments
 
Sec. 30.25  Use of precision specific gravity hydrometers.

    The provisions of Sec. 30.23 respecting the care, handling, and use 
of precision instruments shall be followed with respect to the care, 
handling, and use of precision grade specific gravity hydrometers. 
Specific gravity hydrometers shall be read to the nearest subdivision. 
Because of temperature density relationships and the selection of the 
standardization temperature of 60  deg./60  deg.F., the specific gravity 
readings will be greater at temperatures below 60 degrees Fahrenheit and 
less at temperatures above 60 degress Fahrenheit. Hence, correction of 
the specific gravity readings will be made for temperature other than 60 
degrees Fahrenheit. Such correction may be ascertained by dividing the 
specific gravity hydrometer reading by the applicable correction factor 
in Table 7.

    Example: The specific gravity hydrometer reading is 1.1525, the 
thermometer reading is 68 degrees Fahrenheit, and the true proof of the 
spirits is 115 degrees. The correct specific gravity reading will be 
ascertained as follows:
    (a) From Table 7, the correction factor for 115 deg. proof at 68 
deg.F. is 0.996.
    (b) 1.1525 divided by 0.996=1.1571, the corrected specific gravity.

(Sec. 201, Pub. L. 85-859, 72 Stat. 1358, as amended (26 U.S.C. 5204))