DUCT LEAK TEST FORM
Form EN-MPS-718a FEMC / RPSC Page 1 of 3 Revision 1 9/5/06
Approved by Wayne L. Cornell
ENGINEER DATE (M/D/YYYY) PROJECT STATION MCMURDO PALMER SOUTH
POLE BLDG. NO. BUILDING NAME LOCATION
LEAKAGE TESTS The need to verify leakage control by
field-testing is not present when adequate methos of assembly and
sealing are used. Leakage tests are an added expense in system
installation. It is not recommended that duct systems constructed
to 3-in. w.g. (water gage) class or lower be tested since it is
generally recognized as not being cost effective. For duct systems
constructed to 4-in. w.g. class and higher, the designer must
determine if justification for testing exists. If it does, he or
she must clearly designate the contract documents the portions of
the system(s) to be tested and must specify appropriate test
methods.
GENERAL TESTING PROCEDURES Conventional leak testing is based on
positive pressure mode analysis. It involves inserting temporary
plugs (plates, sheets, balloons, bags, etc.) in openings in a
section of duct and connecting a blower and a flowmeter to the
section of ductwork being tested in such a manner that pressurizing
the duct will cause air escaping from the test section to pass
through the flowmeter.
1. Select a test pressure not in excess of the pressure class
rating of the duct. 2. Calculate the allowable or allocated leakage
using leakage factors related to the duct
surface area. 3. Select a limited section of duct for which the
estimated leakage of duct will not exceed
the capacity of the test apparatus. 4. Connect the blower and
flowmeter to the duct section and provide temporary seals at
all
open ends of the ductwork. 5. To prevent over-pressurizing of
the ducts, start the blower with the variable inlet damper
closed. Controlling pressure carefully, pressurize the duct
section to the required level. 6. Read the flowmeter and compare
the leakage in cfm (cubic feet per minute) per square
foot with the allowable rate determined in Step 3. 7. Complete
test report form (next two pages). 8. Remove temporary blanks and
seals. 9. More detailed information on duct leakage and testing is
available in the SMACNA HVAC
Air Duct Leakage Test Manual. For information on ordering and
prices, write the Sheet Metal and Air Conditioning Contractors
National Association, P.O. Box 221230, Chantilly, VA 20153-1230;
call 703/803-2980; fax 703/803-3732; see www.smacna.org on the
Internet.
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DUCT LEAK TEST (continued)
Form EN-MPS-718a FEMC / RPSC Page 2 of 3 Revision 1
9/05/063/24/2008 Approved by Wayne L. Cornell
TECHNICIAN DATE (M/D/YYYY) PROJECT STATION MCMURDO PALMER SOUTH
POLE BLDG. NO. BUILDING NAME SYSTEM NO. TRAVERSE LOCATION AREA
SERVED/ZONE SYSTEM DESCRIPTION OF DUCTWORK UNDER TEST
DUCT DESIGN OPERATING STATIC PRESSURE W.G. DUCT DESIGN TEST
STATIC PRESSURE W.G. DUCT CAPACITY CFM MAXIMUM ALLOWABLE LEAKAGE:
(DUCT CAPACITY CFM) (LEAK FACTOR ) = CFM
Test Results TEST APPARATUS BLOWER ORIFICE: TUBE SIZE DIAMETER
ORIFICE SIZE DIAMETER CALIBRATED: TEST STATIC PRESSURE: TEST
ORIFICE DIFFERENTIAL PRESSURE: W.G. LEAKAGE CFM CERTIFIED BY:
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