Rev. 13 November 1, 2016
Page | 71- Final Filter Sections
a. All fi lte r racks shall be gasketed.
b. Fina l filters shall be 95% efficient, unless HEPA filters are required for
the spaces being served.
c. Filter access doors shall be specified on both sides of the filter section.
d. Bag f ilters shall not be us ed f or final filters.
e. Design phase selection of coil velocity sha ll be checked to ensure that moi sture does not carry ov er into the
filter section.
f. At project completion, the Contractor sha ll replace all filters. - Blender Sections
a. Specify blender sections for the mixi ng of return air and outside air within each air handling unit i f s pa ce
is availabl e.
b. Arrange duct systems for head-on mixing of the outside air and return air streams.
Also align the control dampe rs in the outside and return air streams for maxi mum mixi ng. - Mist Eliminators
a. Mist eliminators shall be specified where there is potential moisture carryover and in all air handling s ystems
where the design v eloc ity across the c ooling coil i s over 500 fpm. - Anti-Microbial Ultraviolet Emitters for HVAC Ducts and Equipment
a. Provide an automatic switch to de-energize t he e mitters whenever an access door immedi ately on either side
of the cooling c oil is opened.
b. A service switch shall be i ncluded to manually de-energize the emitters.
c. A radiometer shall be spe cified to measure the relative output of each system. The radiometer shall be set
to 100% as s oon as the emitters a re operational.
d. The lamps shall ha ve a separate power source so that the lamps are always energized regardl ess o f t he
operation of the air handling unit.
e. The primary set of lamps sha ll not be installed until after the air ha ndling unit ha s been completed and
cleaned.
f. At pr oject completion, the Contractor shall provide a complete set of replacement lamps. - Humidifiers
a. Steam-to-steam humidifier(s) shall be included for each air handling unit. Refer to AIA Guidelines for
suggested humidity levels.
b. Domestic hot water shall be used for the humidifier make-up, except in Colloton and Carver Pavilions where
special water treatment generates chlorine dioxide or copper and silver ions in the water streams.
c. Two humidistats shall be used to control the humidifier. One humidistat shall be located in the return air
duct and one high limit humidistat shall be located in the supply air duct. Note that there are special care
areas, such as surgery where the humidity sensor shall be located in the occupied area. - Miscellaneous
a. For ganged air handling unit systems, specify tight-sealing isolation dampers to completely block
airflows during maintenance, and backdraft dampers for normal operation periods.
b. Low leakage dampers with quality seals shall be specified for the mixed air and outside air ducts.
c. Linkages for all actuators shall be specified at an angle to allow full closure.