Unit conversions
Used on the ASP. The worked example below is computed by code and checked against the source.
1 ft = 0.3048 m, 1 in = 2.54 cm
1 gal = 3.785412 L, 1 lb = 0.4535924 kg
°C = (°F − 32) ÷ 1.8
Exact or standard factors from NIST SP 811.
Worked example
Convert 55 gal to liters.
55 × 3.785412 = 208.2 L
95°F = (95 − 32) ÷ 1.8 = 35°C.
Where it appears on the exam
ASP: ASP11 Domain 1, Mathematical Calculations
Blueprint: ASP11 Domain 1, task 16: unit conversions (metric/imperial)
Practice: Unit Conversions
Source
The formula comes from
NIST Special Publication 811, Guide for the Use of the International System of Units, Appendix B.8(opens nist.gov in a new tab)“foot (ft) | meter (m) | 3.048 E-01; inch (in) | centimeter (cm) | 2.54 E+00; gallon (U.S.) (gal) | liter (L) | 3.785 412 E+00; pound (avoirdupois) (lb) | kilogram (kg) | 4.535 924 E-01; pound-force (lbf) | newton (N) | 4.448 222 E+00; degree Fahrenheit (temperature) (°F) | degree Celsius (°C) | t/°C = (t/°F - 32)/1.8”
Questions
- What is the formula for unit conversions?
- 1 ft = 0.3048 m, 1 in = 2.54 cm; 1 gal = 3.785412 L, 1 lb = 0.4535924 kg; °C = (°F − 32) ÷ 1.8. Exact or standard factors from NIST SP 811.
- Will this formula be given on the BCSP exam?
- BCSP says the formula is included in the question whenever one is needed, unless the question is testing whether you know the formula. You can't bring a formula sheet into the exam, so learn what each formula does and when to use it.
BCSP on formulas at the exam
BCSP, What to Expect When Sitting for a BCSP Exam (item 7)(opens bcsp.org in a new tab)“For any question requiring a mathematical formula, the formula will be included within the exam question (unless the question is specifically testing your knowledge of a formula). You will not be provided or permitted to bring a formula sheet.”
Related
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- ASP formula sheet
Checked 2026-10-16. Spot a problem? Email hello@passcited.com.