(b) Records. When it is impractical to carry out inspections
concurrently with or shortly after the contractor's performance, the
inspection of records such as work chits, work orders, results of
inspections carried out by the contractor, and vehicle dispatch records is
recommended. The inspection of documents should, wherever possible, be
combined with spot checks of actual work performance.
(c) Management Information System (MIS). MISs usually collect
information over a specified period of time. This information can be
compared to a contract standard. On the basis of this comparison,
performance can be evaluated and the performance for the specified period
can be accepted orrejected.
(1) For example, the vehicle down time rate is computed every
month. A simple comparison of the down time rate with that allowed in the
specifications provides a basis for assessing the adequacy of the
contractor's performance of maintenance of base vehicles.
(2) When a MIS is used as a basis for evaluating the contractor's
work, an assessment should be made of the reliability of the MIS data and
provisions made for checking the accuracy of the MIS data on an ongoing
4-300 METHODS OF SURVEILLANCE.
4-310 General. A number of surveillance methods are available to assess
the quality of the contractor's performance. These methods include 100
percent inspection, planned sampling, random sampling, validated customer
complaints, and incidental or unscheduled inspections. Random sampling
includes random sampling for extrapolated deductions (RSED) and random
sampling without extrapolated deductions (RSWED).
The decision on which surveillance method to use is important, since it not
only determines how the contractor's performance will be inspected, but it
also has a significant impact on the amount of resources that must be
devoted to the QA effort. Each method is described below.
4-320 100 Percent Inspection. 100 percent inspection requires that
output from each and every work occurrence be evaluated. This method of
surveillance is the most thorough method of assessing the contractor's
performance. It is also the most costly.
4-330 Planned Sampling. The defect rate (DR), when planned sampling is
used, is calculated by dividing the total number of observed defects
(including those detected by validated customer complaints and incidental.
inspections) by the total population of services.
Dividing the number of defects in the sample by the sample size gives a
defect rate for the sample only, and the use of this "Observed Defect Rate"
(ODR) to either assess the contractor's performance or take deductions to
the contractor's price is contrary to NAVFACENGCOM policy. This is because