We use witness points to illustrate things that are not significant (or technical) enough to need inspection each time. The QC inspector focuses on those activities during routine inspections and documents only those that are actually witnessed. An example would be "Fitup": every fitup is not required to be inspected by QC prior to weld. However, to raise awareness and improve it is a good idea to check fit ups any time the inspector is around a fitup that is in progress.

Approve: To me this means the appropriate level of personnel has checked the work and verified it is within acceptance criteria. Generally this is indicated with an approval signature. Sometimes it is a QC rep, sometimes a foreman, sometimes a competent person.

Monitor: Routine inspection activity. This type of inspection is usually documented in a log or inspectors diary. Examples may include monitoring the cleaning of a tank, placement of aggregate for civil work, material preparation prior to welding.

Charles

Quality surveillance involves activities that can be quite broad in definition depending on contract and other regulatory requirements. My interpretations of your questions are:

A hold point would be identified as a fabrication step at which inspection and acceptance is mandatory prior to proceeding to the next step. Fabrication cannot continue without inspection.

A witness point is a fabrication step at which inspection and acceptance is required. Fabrication may proceed beyond a witness point provided that verification of the particular task is not obstructed by additional work.

Monitoring would involve random interim visits to confirm activities are in compliance with approved procedures and techniques.

An approval is accepting a task or change as satisfactory based on reports or other information. Approval(s) (such as a change in design, interpretation of contracts or requirements, a nonconformity, deviation or material substitution) are generally the responsibility of the Engineer or other designated responsible individuals. (Often, an Inspector, for example, reviews and accepts reports but generally distributes copies to the Engineer for approval)

The first place you should look is in your company's QC Manual. If it was written correctly you should find the inspection procedures and a definition of terms.

Much to often are inspection terms subject to interpretation. Any posted reply in this thread is also subject to the writers personal interpretation based on his/her background experience or his/her individuals company policy.

If your company does not have a QC Manual, or are still unclear, do not be shy to ask your supervisor. There are no dumb questions.

Mike