Almost all clinical laboratory applications use the metric system to perform systems of measure.
- Length is measured in meters (m) as the base unit.
- Mass is measured in grams (g) as the base unit.
- Volume is measured in liters (L) as the base unit.
Besides temperature, the measures of mass, length, and volume use the same basic structure for increasing or decreasing the measure-based multiples of the number 10. Table 2 demonstrates this standard structure which uses prefixes to identify what multiple of 10 is being measured.
Table 2. Relationship of Metric System Prefixes.| Prefix | Abbreviation | Relationship to the Basic Unit | Relationship to the Basic Unit in Scientific Notation |
| mega | M | Basic unit x 1,000,000 | Basic unit x 106 |
| kilo | k | Basic unit x 1,000 | Basic unit x 103 |
| deci | d | Basic unit x 1/10 | Basic unit x 10-1 |
| centi | c | Basic unit x 1/100 | Basic unit x 10-2
|
| milli | m | Basic unit x 1/1,000 | Basic unit x 10-3
|
| micro | μ
| Basic unit x 1/1,000,000 | Basic unit x 10-6
|
| nano | n | Basic unit x 1/1,000,000,000 | Basic unit x 10-9
|
| pico | p | Basic unit x 1/1,000,000,000,000 | Basic unit x 10-12
|
Measures of temperature are based on 3 main scales—degrees Fahrenheit, degrees Celsius, and Kelvin. Although the Kelvin scale for temperature is used in many chemistry-based applications, the metric system uses degrees Celsius (°C) and is the primary scale for measuring temperature in clinical laboratory applications. The image provides a comparison of the three scales based on the boiling point of water, the freezing point of water, and absolute 0.
