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24 <br />Appendix A - Definition of Terms <br />Commissioning for new buildings, "focuses on verifying and documenting the facility and all of its systems <br />and assemblies are planned, designed, installed, tested, operated, and maintained to meet the owner's <br />project requirements.„19 <br />Commissioning for existing buildings identifies causes and recommends solutions to typical problem <br />areas such as high energy costs and poor comfort or indoor air quality.20 <br />Commissioning is applicable throughout the lifecycle of a building to assure that the building is built and <br />operates as intended. This assurance is needed not only at the beginning of a buildings life (i.e. design <br />and construction) but also when any renovation work occurs as well as periodically during the on-going <br />operation of a building. <br />New construction activities follow the construction process from pre-design planning through design, <br />construction and acceptance. The commissioning provider becomes an integral part of the building team. <br />New construction commissioning may include review and testing of all building systems (security, fire, life <br />and safety, HVAC, lighting, electrical, etc.). Commissioning ends with assuring the operators are trained <br />and O&M manuals are available and accurate. <br />Re-commissioning: No improvements made to systems should be considered one-time, permanent <br />improvements. Systems require on-going inspection and maintenance to ensure proper operation of <br />components. In general, 10-30 percent of energy usage can be saved in systems just by implementing <br />good maintenance practices. <br />Existing building commissioning/retro-commissioning is a periodic event in the life of an existing building <br />that applies a systematic investigation process for improving and optimizing a building's O&M. Much of <br />the service is similar to that for new-construction commissioning. The O&M staff work alongside the <br />commissioning authority as they check equipment and make adjustments. Retro-commissioning usually <br />focuses on energy-using equipment such as mechanical equipment, lighting, and related controls with the <br />goal of reducing energy waste, obtaining energy cost savings for the owner, and identifying and fixing <br />existing problems, using diagnostic testing and O&M tune-up activities. <br />Degree days: includes Heating Degree Days (HDD) and Cooling Degree Days (CDD). A degree day is <br />a measure of heating or cooling. Totalized degree days from an appropriate starting date are used within <br />energy monitoring and targeting to monitor the heating and cooling costs of climate controlled buildings, <br />while annual figures can be used for estimating future costs. <br />A zero-degree-day in Energy monitoring and targeting is when either heating or cooling consumption is at <br />a minimum, which is useful with power utility companies in predicting seasonal low points in energy <br />demand.21 Degree-day figures quantify how cold (or hot) the weather has been in a given region, <br />expressing the result as a single index number for each month or week. <br />Degree day calculations are necessary when comparing energy use for two- different time periods. For <br />example, the amount of energy required to cool the same building will be very different during a moderate <br />summer with average temperatures than it will be for a summer such as was experienced in 2010 with <br />record high temperatures. Similarly, more energy will be required to heat a building during periods with <br />below average temperatures. 2010 brought periods of record low temperatures as well, requiring more <br />energy to heat facilities than for the comparable time period in previous years. <br />Heating and cooling degree days are calculated by using the average temperature for the day (the high temperature <br />added to the low temperature and the sum divided by two) and then subtracting the average temperature from the <br />number 65 for heating degree days or subtracting 65 from the average temperature for cooling degree days. The <br />number 65 is used as the base number because most buildings and homes would be most comfortable and energy <br />efficient at our around 65 degrees. <br />19 ASHRAE Draft Guideline 0-2003 <br />20 WA Department of General Administration <br />21 httn://en.wikipedia.org/wiki/De~ee day <br />