1.1 This practice covers simple methods for calculating how many units to include in a random sample in order to estimate with a specified precision, a measure of quality for all the units of a lot of material, or produced by a process. This practice will clearly indicate the sample size required to estimate the average value of some property or the fraction of nonconforming items produced by a production process during the time interval covered by the random sample. If the process is not in a state of statistical control, the result will not have predictive value for immediate (future) production. The practice treats the common situation where the sampling units can be considered to exhibit a single (overall) source of variability; it does not treat multi-level sources of variability.
| SDO | ASTM: ASTM International |
| Document Number | E122 |
| Publication Date | Oct. 1, 2007 |
| Language | en - English |
| Page Count | 5 |
| Revision Level | 07 |
| Supercedes | |
| Committee | E11.10 |