Substitution of Test SamplesA foreman of a road maintenance contractor, under the supervision of a consultant’s works supervisor, was tasked to obtain samples of bituminous material cores from a road resurfacing site and deliver the samples to the laboratory for testing. Investigation revealed that the foreman had fabricated a number of test samples, which were used to replace any substandard ones obtained on site. The malpractice was discovered by the works supervisor during his routine inspections. The foreman gave a gift cheque of a few thousand dollars wrapped in an envelope to the works supervisor as a reward for the latter’s conniving at the malpractice.
Case in Perspective
Construction materials testing process is vulnerable to corruption and malpractices, in particular when there is a lack of proper and effective supervision in the selection, safekeeping and transportation of test samples. However, in order to avoid contractual liabilities due to failure of compliance tests (e.g. deduction of contract payments), unscrupulous contractors and/or sub-contractors may manipulate the process to ensure that only compliant samples are selected for testing. They may also cover up substandard materials or works through substitution of test samples or falsification of test reports, with the corrupt connivance of site supervisory staff and/or laboratory technicians. The above malpractices not only render the parties concerned liable to prosecution, but also undermine the works quality and put the public safety at stake.
Therefore, project owners/clients should put in place adequate and effective safeguards to prevent corruption and malpractices in the material testing process in their construction projects, including, but not limited to, the following -
(a) Laying down clear procedures for the selection, safekeeping and transportation of test samples;
(b) Keeping all selected samples in safe custody throughout the process until handing over to testing laboratories;
(c) Requesting laboratories to submit test reports and certificates directly to the project owners/clients or their consultants; and
(d) Where necessary, appointing independent laboratories to conduct parallel tests on materials.