› Sampling Plan; CSP-1 Plan







Hello fellow Quality Profesionals,

I am trying to implement a supplier certification program, and recently I was suggested to use the CSP-1 Plan. When researching a little into the plan, I discovered different "f" and "i" values for AOQL levels of 4.94, and 6.0. However, I cannot find a table including different "f" and "i" values for an AOQL of 5%.

Does any one have a table including the "f" an d"i" values with an AOQL of 5%? I currently have;
..i ........ f
12 .... 1/4
14 .... 1/5
21 .... 1/10

The formula in exel will be appreciated if the table is not available.

Thank you,


Sampling Plan CSP-1

4.94% is the closest you will find in the Mil Std 1235C
The Continuous Sampling Plan CSP-1 is for application to continuous production meaning that each unit is inspected as it is produced. Application of this sampling methods is for product flowing in assembly-line fashion. The sampling plan also requires a homogeneous production system. All units must be made in accordance with the same specification under stable conditions of production (in statistical control). Any interruption in the production process, like the change of material source, change of tooling, or stopping of production, is assumed to terminate a production run homogeneous conditions.

The procedure is:
1) Begin with 100% inspection of the units consecutively as produced and continue this inspection until i units in succession are found clear of defects.

2) When i units in succession are found clear of defects, then discontinue 100% inspection, and inspect only a fraction f of the units, selecting individual sample units one at a time from the flow of production, in a manner to assure an unbiased sample.

3) If a sample unit is found defective, immediately return to 100% inspection of succeeding units and continue until i units in succession are found clear of defects.

4) Correct or replace, with good units all defective units found.

Average Outgoing Quality Limit (AOQL)
The highest/worst possible average percent of non-conforming items in the process, after employing some inspection scheme. This measure is usually used in rectifying inspection, where the inspection procedure changes the outgoing rate of non-conforming items in the batch or process, relative to the incoming rate. For example, by removing the non-conforming items that are encountered during inspection. Note that this is only the worse possible average percent of non-conforming items, and therefore there is still a possibility that the percent non-conforming of a single batch will exceed this limit.
AOQL = 4.94%

Sampling fraction f Clearance Number i
0.50 6
0.33 10
0.25 13
0.20 15
0.14 18
0.10 22
0.07 27
0.04 33
0.02 42
0.01 52
0.01 62
I hope this helps. Best Regards, David L. Hunt, ASQ Certified: SSBB, Quality Manager, CQE, CQA