Question

For the purpose of sampling inspection, the maximum percent defective that can be considered satisfactory as a process average is
1. Rejectable Quality Level (RQL)
2. Acceptable Quality Level (AQL)
3. Average Outgoing Quality Limit (AOQL) 
4. Lot Tolerance Percent Defective (LTPD)

Answer 1

Correct Answer - Option 2 : Acceptable Quality Level (AQL)

Concept:

The operating characteristics curve for an attribute sampling plan is a graph of fraction defective in a lot against the probability of acceptance.

For different sampling plans, the operating characteristics curve will be different. To construct we should know the mathematical probability of accepting lots with varying percent defectives.

Acceptance Quality Level (AQL):

• AQL represents the maximum proportion of defectives that the consumer finds definitely acceptable.
• Ideally, at AQL the probability of acceptance should be one i.e.100%. The probability of rejecting the lot at AQL represents the producer’s risk.

Rejection Quality Level (RQL):

• RQL represents the proportion of defects that the consumer finds definitely unacceptable. The probability of accepting a lot at the RQL level represents the consumer’s risk.
• It is also called Lot Tolerance Percentage Defective (LTPD).