Labconco Protecto PVC Laboratory Fume Hoods 14181 Series - Manuel (Page 12)

Chapter 2: Prerequisites
Product Service 1-800-522-7658 8
Original instructions
Proper PVC blower selection can be determined from these exhaust requirements
and the total system static pressure loss. Contact Labconco Customer Service for
assistance in sizing a blower system.
Exhaust Washdown Requirements
The entire exhaust duct system must feature an adequate washdown system. This
includes the exhaust ductwork, blower, hood structure itself, and any ductwork
located outside the blower. Wash rings are required to be placed in the exhaust
duct system every 8 to 10 feet and after any change in direction to provide
adequate washdown. Contact Labconco for washdown ring ordering information.
Order part number 4746000 for a 10" wash ring and 4746100 for a 12" wash ring.
Depending on the length of duct run and number of wash rings and elevation
differences, Labconco recommends one additional washdown valve for every
three wash rings. The washdown nozzles are designed at a normal pressure of 40
psi with a flowrate of 1 gallon per minute and a minimum pressure of 10 psi with
a flow rate of 0.5 gallons per minute. The washdown nozzle at a maximum
pressure of 100 psi has a flowrate of 1.5 gallons per minute. Each washdown
valve can only produce up to 3.5 gallons per minute at 40 psi and additional
washdown valves are ordered frequently and installed on the fume hood front
corner post. Order 9808310 Washdown Valve Kit (3/8 lines) per sizing chart that
follows.
Airflows and Static Pressure
Eco Energy Saving Air Foil
Hood Type Face Velocity (fpm) Airflow Volumetric Rate (CFM) @
Sash at Sash at 62.5% Static Pressure (inches of water)
Full open open 4' 5' 6' 8'
PVC
at 28" at 18" Hood Hood Hood Hood
Hoods
Perchloric
125 200 905, 0.27" 1195, 0.44" 1475, 0.59" 2050, 0.35"
and
100 160 725, 0.17" 955, 0.28" 1180, 0.38" 1640, 0.22"
Acid
N/A 125 565, 0.11" 745, 0.17" 920, 0.23" 1280, 0.13"
Digestion
N/A 100 455, 0.07" 595, 0.11" 740, 0.15" 1025, 0.09"
12.75" OD
Exhaust Recommendations highlighted