SAMPLE HOSPITAL SOLUTION
Hospitals increasingly seek clean disinfected air, and one of the most cost-effective solutions is integrating an array of linear Ultraviolet-C (UVC) lamps to both clean the Coil and clean the Air on the Duct supply side. The sample solution below is for a large size Air Handling Unit (AHU) with the Coil, Plenum, primary Duct, and air flow illustrated in the figures
Elevation of Coil (left) Cross Section of Plenum (right) feeding into Ducts
This example above is for a property with multiple air handling units. This particular AHU-1 has three rows of two coils that are each 8’ wide x 3.5’ tall. The six coils are stacked three high in the plenum that is 16’ wide x 11.5’ tall. The CFM is 73,600 and the approximate square footage of the conditioned area for this ACH-1 is 60,000 SF
Coil + Air Disinfection UVC System:
The PV-AUV-CK Series is a modular system (like an Erector Set – known perhaps to many of you who grew up before online games). The modular system is assembled on-site and includes the following:
(3) PV-AUV-CK-8 – $4,200 (Electrical Enclosures with 8 ballasts @ $1,400 each)
(24) PV-AUV-GSL-48 lamps – $3,480 ($145 each)
(24) 30 ft lamp cables – $1,800 ($75 each with SureSeal connections)
(48) lamp clamps – $480 (2 per lamp @ $10 each)
(2) switches – $170 ($85 each)
(2) warning signs $20 ($10 each)
Equipment Cost: $10,150
For this air handler each of the (24) UVC lamps are 48” linear “tube” modules. Given the 73,600 CFM and the plenum size of (16′ x 11.5′ = 184 SF), the air velocity is 400 feet per minute in the plenum (73,600 CFM / 184 SF).
24 lamps effectively clean the coil and provide the adequate dose of ultraviolet irradiation to also clean the air. Dose is based on time, intensity, and distance. Each of the (24) 48″ high powered UVC lamps is 119 watts, for a total of 2,856 watts. The resulting dosage is 88,250 μW·s/cm2 (micro-Watt seconds per square centimeter), which is also expressed as microjoules per square centimeter or 88.25 joules per square centimeter. The key with this system is to set the lamps on the downstream supply side far enough away from the coils so that they can clean the air on both sides of the lamps. The ideal distance from the coil is 18″ (in this case with the plenum length of 6′ along the path of air flow). The longer the pass through “purge zone” the better, since the air is moving fast, and time is a factor of dosage.