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October 2011 www.sname.org/sname/mt LEED certication is a feasible segue for shipyards to welcome new green business by establishing credibility as environmen- tal stewards. Technologies Indoor environmental quality. Indoor environmental qual- ity (IEQ) pertains to the myriad contributing factors aecting the health and comfort of occupants in an enclosed struc- ture. IEQ onboard a government or military vessel is critical to maintaining the health and readiness of its personnel. IEQ encompasses lighting levels, controllability of systems, noise, and indoor air quality (IAQ). The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 62.1 2004 ? Ventilation for Acceptable Indoor Air Quality addresses the technologies associated with achieving minimum ventilation rates and acceptable indoor air quality to minimize adverse health eects. ASHRAE standards are typically pertinent in commercial land-based purposes, but the benets of its application can be realized in the maritime industry as well. Ventilation dependent upon rate of respiration is one such rel- evant method for future government ships to ensure adequate air intake and distribution for its personnel. Respiratory controlled ventilation. Demand control ven- tilation (DCV) technology is poised to become the industry standard control system for maintaining desired ventila- tion levels. One application of DCV utilizes CO 2 sensors that modulate the supply of outdoor air percentage, which is dependent upon personnel occupancy and corresponding metabolic activity. CO 2 sensors dier from other sensors in that they monitor the byproduct of respi- ration rather than detect levels of indoor pollutants. e oper- ation of a ventilation system controlled by demand via continu- ous space monitoring and feedback ensures sucient air changes. DCV is not practical for all shipboard appli- cations. The appropriation of DCVs commercial capabilities needs further study to ascertain the full extent of its maritime potential. Certain shipboard areas have pressurization requirements with their own dedicated exhaust systems (such as laundry, ammable storage, and galleys). Recommended installations include areas with high volume, rapid turnover, and similar zone requirements for heating and cooling. On a government ship, this could be applied to accommodation spaces that have unpredictable schedules of personnel turnover and an array of metabolic activities such as sleeping, light work, and heavy exercise. Energy ecient system selections and practices. Energy management is a continuous measurement and verication process, requiring the concerted development of applied tech- nologies, ongoing maintenance, diligent record keeping, and organizational commitment. Energy cost saving measures (ECM) and IAQ consider- ations have mutually exclusive goals with aggregate results; therefore, independent ECM and IAQ planning is a vacuous notion. ese two metrics require an intricate balance in order to prevent defunct outcomes. For example, increased ventila- tion to satiate IAQ concerns would oset energy conservation. A compromise on target ventilation eectiveness needs to be established because higher percentages of OA increase the electrical demand required to treat unconditioned air. Shipboard energy management system. A shipboard energy management system (EMS) with direct digital controls is the necessary interface to establish HVAC trend analysis into a consolidated user end graphics display. HVAC trend analysis is an instrumental approach to examining the simul- taneous interaction of system components over long durations and varying conditions?a practice ideal for shipboard appli- cation. e installation of a trend analysis program alone does not constitute any eciency or IAQ improvements, but pro- vides a quantitative visual tool for assisting management in making more informed decisions to improve upon existing HVAC operations and auxiliary systems. Shipboard EMS parallels the network-centric? concept of the Navys littoral combat ship program. Similarly, the next government ship should have graphic analysis tools, automated trend identication, and enhanced conguration control. Electrical load disaggregation is not an established met- ric for energy stakeholders in the maritime industry. Without For future classes of vessels, the government needs to take a holistic approach towards energy-ecient HVAC design. The selective catalytic reducer, like this FME model, converts nitrogen oxides, also referred to as NO X with the aid of a catalyst into diatomic nitrogen, N 2, and water, H 2O. Marine propulsion systems that meet IMO tier III emissions standards are likely to include this type of unit. Adapting the Model