Published on July 2, 2018.

And One More Thing…

Additional lessons learned from commissioning megaoccupancies


There are many more takeaways we have observed in our commissioning experience with very large buildings in Macau, of course.

In the design phase, for example, it is very important to ensure that emergency first responders are provided with the building features necessary to do their jobs. The design and installation of fire and life safety systems, along with the building architecture and all other systems, must be coordinated with first responder needs. The list typically includes fire department standpipe locations and connections, fire department elevator control functions, elevator recall functions, fire alarm annunciator locations, and voice and printed language preferences, to name a few. These kinds of features are typically not negotiable; even if an equivalency is proposed, it is best that the equivalency provide a better solution than the mandated minimum, and it will always require buy-in from the authority having jurisdiction before it is adopted.

In the construction phase, added diligence around the most complex integrated testing challenges will pay off over the course of the project. Large assembly-use areas such as theaters and event centers present particularly complex cohesive operations. These areas often require the integration of audio and lighting systems, whereas the entertainment amplifiers are shunted and the required illumination levels restored upon activation of the premise’s fire alarm system. Independent emergency voice/alarm communication controls are usually provided along with a smoke control system to address a stage’s architecture and/or restricted aisle widths that require smoke-protected seating. Specialized theaters may opt for a deluge water curtain instead of a fire-resistance rated proscenium curtain, an approach that often requires the integration of a fire or flame detection system. That system is sometimes monitored by the same or separate fire alarm panel, which if activated requires a solenoid releasing function of the sprinkler deluge valve—all of it and more being monitored and/or controlled by the fire detection and signaling system.

Witnessing the correct sequence of operation of these systems during testing is extremely satisfying to the engineering nerd in all of us, but we must always remember that system complexity increases the chance for false or nuisance alarms. This is especially true when you’re dealing with designers, contractors, and installers with limited experience involving these complex systems and their integration. Keeping a sharp eye on the commissioning and testing processes in megaoccupancies is absolutely essential.

That’s also why it’s essential to keep rigorous records to track the commissioning process. It is common for Macau commissioning teams to witness acceptance testing before the final integrated commissioning tests. Also, due to the size of the systems, it is common to witness the acceptance testing of the system in phases, where a predetermined section is completed before additional sections are brought online. Regardless how it happens, it’s a lot to keep track of, which is why careful record keeping is required by both NFPA 3 and NFPA 4. Both standards call for commissioning tasks and results to be tracked on daily activities, and non-compliance reports that formulate the issues are logged for each system.

The Sands Cotai Central, for example, has a footprint over 1.1 million square feet, and the project generated over 15,000 defects that were tracked during a commissioning effort that exceeded 20 months. Sorting this information by discipline and location allows program managers to send daily reports to the responsible contractors, even when there are multiple contractors installing the same type of system. One project required seven sprinkler contractors because the scope of the work was beyond the local capabilities of any single contractor.

ROBERT KEOUGH, P.E., FSFPE, SET, is sr. vice president, Pacific Rim Operations, for Jensen Hughes. DAVID LEBLANC, P.E., FSFPE, is a vice president and commissioning service lead for Jensen Hughes. Top Photograph: Getty Images