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Commissioning: Fair and Balanced

In my October and November, 2006 columns I explored the complexities associated with motivating contractors to install, startup, and test new building systems as required to have the commissioning testing and demonstration be successful the first time. If there is an incentive for deficiency-free test results, the Commissioning Professional needs to be wary of the contractors wanting to stop and “fix” deficiencies during the testing process.

When only failures that remain at the end of a system test are counted towards a success metric, there can be great pressure from the contractor to stop the test, correct the problem, retest the failed step, and then move on. Although this should be allowed within reason (a rule of thumb would be to give the contractors 5 minutes to fix a problem), it is more likely to be abused if there is a “scoring” incentive to field-correcting deficiencies. Interrupting tests for work that should have been performed as part of the contractors’ quality control program is not a good use of the commissioning team schedule and budget resources.

I recommend that if some aspect of a test does not achieve the documented acceptance criteria, it should be counted as a deficiency – whether or not it is corrected in the field. The success metric needs to reflect the system operation when the test is started, not when the test is completed. This should motivate the contractors to be ready for system demonstration and not use the commissioning tests as their quality control process. It will also help keep the field testing/demonstration process moving without too much strain on the Commissioning Professional.

If the Commissioning Professional is put in a position of granting the contractors field time to correct a problem and not have it count as a deficiency, the contractors will put substantial pressure on the Commissioning Professional to let them do just that. In practice, this is a very subjective decision that depends on time of day, type of deficiency, the Commissioning Professional’s relationship with the contractors, etc. An individual Commissioning Professional will have difficulty being consistent (fair) when making these decisions. In a large project with multiple testing teams, it will be virtually impossible for the commissioning personnel to be consistent with each other.

In order to avoid disagreements regarding subjective matters of fairness and consistency, I recommend sticking strictly to the pass/fail test acceptance criteria as the sole determination of success. Under no circumstances should the initial failure to achieve the documented acceptance criteria be removed from the commissioning record. If the contractor wants to take a specified minimum time period (e.g., 5 minutes) to correct a problem in order to avoid both the contractor and the Commissioning Professional from having to track, document, and retest the correction in the future, that should be allowed. However, it is best to maintain the 5 minute time limit without exception, again to avoid the appearance of inconsistency and to respect the testing team’s time.

To have a fair and sustainable incentive program, it is important to avoid penalizing the contractors for things they can not control. As noted above, the goal is to encourage the contractors to do their jobs well in preparation for the commissioning demonstrations. Ideally, this means running through the functional performance test procedure for each system on their own prior to officially demonstrating system operation to the Commissioning Professional. Therefore, the only deficiencies that should count against a success metric would be those that could have been found and corrected by the contractors prior to commissioning testing.

Preventable failures are typically those associated with system integration and control system programming. Equipment failures are often unpredictable and covered by manufacturers’ warranties and, thus, fall into a different category with respect to system functional performance demonstration. When developing motivational strategies for reducing/eliminating failures, it is important to recognize these differences and what the commissioning team members can and can not control.

This concludes the current discussion of failure management and incentive programs. In summary, it is important to note – for all commissioning team members – that commissioning is more than just looking for problems. The value of commissioning comes not from finding and documenting deficiencies; it comes from avoiding problems that may limit the ability of the building owner to make the best and most efficient use of the new systems upon construction completion.

In the purest sense, commissioning is not about problems at all; it is about demonstrating compliance with the design intent and the construction document requirements. Until commissioning is truly successful and all test procedures pass the first time, we need to continue to improve towards the goal of the “perfect test.”

 

COMMISSIONING: GETTING IT RIGHT

Engineered Systems, December, 2006

by
Rebecca Ellis, PE, LEED AP, CCP, CxA
President
Questions & Solutions Engineering
1079 Falls Curve
Chaska, MN  55318
rteesmag@QSEng.com