政策法规现行有效美国危险品合规

§ 171.10 Units of measure.

效力	法规类型	发布日期	生效日期	发文机构
现行有效	部门规章	2026-08-07	2026-09-08	Code of Federal Regulations (CFR) - Transportation (Title 49)

发布08-07

生效09-08

摘要总结AI 辅助解读

该条款规定美国危险品运输法规（49 CFR Part 171）中计量单位的法定标准。核心原则是：国际单位制（SI/公制）为唯一监管标准，括号内的美制单位仅供参考，不具备法律效力。所有申报、标签及文件必须严格依据 SI 单位进行合规性判定。若使用美制单位导致数值换算误差从而违反安全限值，将被视为违规。建议相关方在制作单据时以 SI 数值为准，避免依赖括号内参考值。

(a) General. To ensure compatibility with international transportation standards, most units of measure in this subchapter are expressed using the International System of Units (“SI” or metric). Where SI units appear, they are the regulatory standard. U.S. standard or customary units, which appear in parentheses following the SI units, are for information only and are not intended to be the regulatory standard.
(b) Abbreviations for SI units of measure generally used throughout this subchapter are as shown in paragraph (c) of this section. Customary units shown throughout this subchapter are generally not abbreviated.
(c) Conversion values. (1) Conversion values are provided in the following table and are based on values provided in ASTM E 380, “Standard for Metric Practice”.

- (2) If an exact conversion is needed, the following conversion table should be used.

Table of Conversion Factors for SI Units Measurement SI to U.S. standard U.S. standard to SI Activity 1 TBq = 27 Ci 1 Ci = 0.037 TBq Length 1 cm = 0.3937008 in 1 m = 3.280840 ft 1 in = 2.540000 cm 1 ft = 0.3048000 m Thickness 1 mm = 0.03937008 in 1 in = 25.40000 mm Mass (weight) 1 kg = 2.204622 lb 1 g = 0.03527397 oz 1 lb = 0.4535924 kg 1 oz = 28.34952 g Pressure 1 kPa = 0.1450377 psi 1 Bar = 100 kPa = 14.504 psi 1 kPa = 7.5 mm Hg 1 psi = 6.894757 kPa 1 psi = 0.06895 Bar Radiation level 1 Sv/hr = 100 rem/hr 1 rem/hr = 0.01 Sv/hr Volume (liquid) 1 L = 0.2641720 gal 1 mL = 0.03381402 oz 1 m 3 = 35.31466 ft 3 1 gal = 3.785412 L 1 oz = 29.57353 mL 1 ft 3 = 0.02831685 m 3 Density 1 kg/m 3 = 0.06242797 lb/ft 3 1 lb/ft 3 = 16.01846 kg/m 3 Force 1 Newton = 0.2248 Pound-force 1 Pound-force = 4.483 N Abbreviation for units of measure are as follows: Unit of measure and abbreviation: (SI): millimeter, mm; centimeter, cm; meter, m; gram, g; kilogram, kg; kiloPascal, kPa; liter, L; milliliter, mL; cubic meter, m 3 ; Terabecquerel, TBq; Gigabecquerel, GBq; millisievert, mSv; Newton, N; (U.S.): Inch, in; foot, ft; ounce, oz; pound, lb; psig, psi; gallon, gal; cubic feet, ft 3 ; Curie, Ci; millicurie, mCi; millirem, mrem.

[Amdt. 171-111, 56 FR 66159, Dec. 20, 1991, as amended by Amdt. 171-136, 60 FR 49108, Sept. 21, 1995; Amdt. 171-135, 60 FR 50302, Sept. 28, 1995; 66 FR 33335, June 21, 2001; 66 FR 45378, Aug. 28, 2001; 68 FR 75740, Dec. 31, 2003]