Consulting-Specifying Engineer - May 2008 - (Page 52) a normal project. Clearly and thoroughly defining the requirements and the process from the project outset is necessary to achieve this end result. Design phase: The design phase is where the design team creates construction documents in accordance with the OPR. During this phase, the CxA must ensure the systems and facility proposed will meet the OPR. It is also key to ensure requirements of the contractors and define the Cx process, including testing plans and acceptance criteria. Critical facilities will require considerably more verification testing than other types of projects. The training requirements must be included in the appropriate equipment sections to ensure that sufficient training is provided to allow the owner’s O&M staff to operate the facility as intended. Critical facilities will require considerably more verification testing than other types of projects. the Cx requirements are detailed in the construction documents and in the CP. Major steps in this phase include: • Review Basis of Design (BOD) • Ensure Cx requirements are detailed in specifications • Define operator training requirements • CxA reviews design documents and resolves issues. The CxA must review design documents from the BOD through the issuance of construction documents. The reviews need to focus on the documents ability to meet all aspects of the OPR with sufficient detail to ensure the contractors can fully understand the system requirements. It is essential that the documents do not leave the contractor to interpret any part of the system sequence, which often results in “this is how we always do it” or “this is how we did it on my last project” reasoning that leads to deficiencies. The CxA and design team should meet to ensure that any issues identified are understood by the designers and resolved in a manner that satisfies the owner. In particular, design operating sequences need careful attention. The system sequences must be fully developed to ensure every operating condition is clearly defined, including normal operations, staging up/down, failure, and emergency sequences. The specifications should detail the Construction phase: This is the phase most people associate with Cx, however, if the steps in the previous phases have not been correctly implemented, this phase will be difficult to complete successfully. Key steps in this phase include: • Submittal/O&M review • Detailed test procedure development /execution • Installation verification and startup testing • Verification testing • Training verification. The CxA will review the submittals to ensure the equipment will meet the OPR and can be properly commissioned. Key items to focus on in submittal review are part-load conditions due to concurrent operation of redundant equipment, and ensuring the operating sequences are detailed in control systems documents. The approved submittals and O&M manuals will be used to develop the installation, startup, and functional testing procedures. The sequences in critical facilities are not standard. Generic or canned test procedures will not test all required sequences nor detail the expected results. The test procedures must detail all sequences and required results for the specific systems installed. Verification of the HVAC systems balancing will need to be performed on 100% of the critical systems prior to functional testing. Functional testing of mechanical systems that cannot deliver or receive design flow will not provide accurate test results. Because there so many complex interlocks and redundancies on systems in critical facilities, the CxA executing or witnessing tests must have the experience to identify possible failures or system shortcomings that are not obvious to the untrained eye. Simply observing tests and checking boxes that they occurred does not provide quality service. Due to the complexity of critical facility operation, the O&M staff must be properly trained to understand the operation of all equipment, systems and sequences. For the sustainability of the site, the O&M staff must understand and be comfortable with all of the systems in all their conditions, from routine to fire, power, and other types of emergencies. Operations and occupancy phase: The Cx team should assist in coordinating contractor callbacks and perform any deferred systems testing. Additionally, the Cx Team should work with the Owner’s Operations and Maintenance (O&M) staff to identify systems not operating efficiently, including causes and solutions to return the systems to efficient operation. Key steps in this phase include: • Deferred testing • Warranty site visit • Enhanced O&M staff training • Lessons-learned workshop. While performing the deferred testing and warranty site visit, the CxA should go over the operation of the facility with the O&M staff, identifying any issues the group may have with system/component operation. The CxA should provide additional training to the staff as necessary to provide the staff with the knowledge and comfort level in the system operation. Who does what? The second critical factor in the Cx approach is identifying the qualifications of the personnel required to facilitate the depth and rigor of the process. With all of the tasks associated with the process, how do you determine “Who does what?” The CxA and owner need to 52 Consulting-Specifying Engineer • MAY 2008
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