Plastics : Sampling Requirements, Sample Size Determination and Acceptance/Rejection Criteria

Sampling:

Sampling is the process of selecting and testing a representative portion of a larger group or a lot to make decisions about the entire group's quality.

Sample Size Determination:

Based on lot size:

The below diagram showssamples sizes based on lot size.

Acceptance/Rejection Criteria:

For Critical Defects (0.065%): Defects that make the product unsafe or unusable, posing safety risks or regulatory non-compliance.

Accept: 0 (zero) defects
Reject: 1 (one) or more defects

For Major Defects (1.5%): Defects that significantly affect product function, performance, or appearance but don't pose safety risks.

For Minor Defects (2.5%): Defects that slightly affect appearance but not function or safety.

Key points to remember regarding defects:

• Critical defects are never acceptable
• Major defects significantly impact function
• Minor defects are mainly cosmetic