PIC Quality Acceptance Sampling 3

Question 1

A nuclear density gauge reading shows 93.5% of the maximum theoretical density (MTD). The specification requires a minimum of 92%. What is the inspector's correct action?

Accepted Answer

Accept the area; it meets the density specification

Answer

93.5% MTD exceeds the 92% minimum, so the area passes the density requirement and should be accepted.

Question 2

Which factor most directly affects the reliability of a field-extracted asphalt core for density testing?

Accepted Answer

Core location relative to longitudinal joints and wheelpath

Answer

Cores taken near joints or wheel paths can yield anomalous density readings that do not represent the broader lot quality.

Question 3

What is the purpose of a random number table or random number generator in acceptance sampling?

Accepted Answer

To remove inspector bias in selecting sample locations

Answer

Random number tools ensure sample locations are selected without intentional or unintentional bias, supporting statistical validity.

Question 4

When using the 'percent within limits' (PWL) method, a higher PWL value indicates:

Accepted Answer

A greater proportion of the lot meets specification limits

Answer

PWL represents the estimated percentage of the lot that falls within upper and lower specification limits; higher PWL means more conforming material.

Question 5

An inspector notices that all density cores from a lot were taken in the center of the lane, away from edges. This sampling approach is best described as:

Accepted Answer

Biased sampling that may overestimate lot quality

Answer

Sampling only the center of lanes avoids areas that typically have lower compaction (edges), introducing bias that inflates average density results.

(PIC) Paving Inspector Certification Practice Test

(PIC) Paving Inspector Certification Practice Test

PIC Quality Acceptance Sampling 3