23 05 93 Attachments.pdf

Level 2 – Duct Air Leakage Test (DALT) Procedure - Constant Pressure Method ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (revised 3/29/2021)

Summary of Method:

The constant pressure method is useful for testing small volumes and is conducted at the maximum operating pressure for the system. All components that are part of the pressure boundary including ducting, fans, dampers, housings, flex connections, shaft seals and any other components forming the pressure boundary shall be tested to verify leak tightness. Temporary sealants, duct tape, or similar temporary materials SHALL NOT BE USED except for sealing the temporary blank‐off panels. If the measured leak rate exceeds the permissible leak rate, the leaks shall be located by one of the methods listed in this procedure and repaired. The section shall then be retested per this procedure to verify leak‐tightness.

NOTE:

This test procedure is written as if operating pressure is positive, but it would be identical for negative pressure systems with appropriate change in signs used in the data collection and calculations.

Pre-requisites:

Construction, modifications, and repairs affecting the test boundary shall be complete and the inlet and discharge openings of the section shall be sealed before the test is started. All electrical, piping, and instrument connections shall be complete and all permanent seals shall be installed before the test is started.

Test equipment:

(a) pressurization source capable of producing the specified positive or negative pressure

(b) covers to seal test boundaries

(c) clock or timer

(d) pressure-indicating device for test volume – (this procedure assumes pressure instrumentation reading in “inches of water” (“wg)).

(e) temperature-indicating device for test volume– (this procedure assumes a temperature indicating device reading in degrees Fahrenheit).

(f) bubble solution for detecting air leaks (bubble method)

(g) optional portable electronic sound detection equipment (audible leak method)

(h) flowmeter

(i) totalizing gas volume meter

Reference:

(a) ASME AG‐1‐2015; Article TA‐III Duct and Housing Leak Test Procedural Guidelines; TA‐III‐4100

CONSTANT PRESSURE TEST.

(b) DOE –HDBK‐1169‐2003; Table 5.6 – Recommended Maximum Permissible Leak rates at 2 in.wg

Negative

SECTION 23 05 93 ATTACHMENT A

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (revised 3/29/2021)

Procedure:

1. Obtain a “Level 2 Duct Air Leakage Test (DALT) RECORD –“Constant Pressure Method” sheet.

2. Complete the header table for each sheet, (that each sheet may be traced to a unique testing event).

-Date of Test

-Section I.D. # being tested * -Description of Section Tested -Test Attempt Number for this Section (Sequentially Numbered)

*Provide a marked up drawing identifying the boundaries of the tested Section, and include as an Attachment to the Test Record Sheet.

3. Fill in the Table #1 Instrumentation Information for the Pressure Gage, Flowmeter, Thermometer; and sign that the information is correct.

4. The Government will complete Table 2 for “LEAK RATE CALCULATIONS” of the DALT Record Sheet.

‐Maximum system flowrate Q Full System , in units cubic feet per minute (cfm).

-Record on Table 2 Line 1

-Maximum operating pressure from the level 2 side of the system OP Full System , in units inches-water gage (“wg).

-Record on Table 2 Line 2 Use appropriate sign as applicable for positive (+) or negative (-) pressure systems.

5. Using the equation for L2 Full System , for a Level 2 test, calculate the permissible leak rate for the full Level 2 side of the system at 2”wg:

𝑳𝟐 Full System = . 𝟎𝟏 QFull System -Record on Table 2 Line 3

6. Calculate the permissible leak rate at Test Pressure for the full Level 2 side of the system, LP(Full System), using OP(Full System) from Table 2 Line 2.

𝑳𝑷 Full System =𝑳𝟐 Full System 𝑶𝑷 , 2⁄ - Record on Table 2 Line 4

This is the limit for allowable leakage for the entirety of the level 2 ductwork if tested as a complete assembly and as a singular test.

If the Level 2 ductwork is to be tested in subsections, a representative proportion of the acceptable leak rate must be determined and assigned to each fractional test section such that the sum of all the permissible leak rates of the sections does not exceed the permissible leak rate as if it were tested as an assembly in its entirety. Proceed with steps 7 through 13 for correcting for permissible leak rate of sections.

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (revised 3/29/2021)

7. Determine the Volume for the full extent of the level 2 portion of the system V(Full System) and record on Table 2, Line 5.

8. Determine the maximum anticipated operational pressure for the section to be tested OP Section and record on Table 2, line 6.

9. Determine the volume of the pressure boundary for the section to be tested V(Section) and record on Table 2, Line 7.

10. Determine the percentage that V(Section) is of the whole level 2 volume of the system V(Full System) using the following formula: V% = V(Section)/V(Full System) and record on Table 2, Line 8.

11. Calculate permissible the leak rate for the section to be tested using the highest operational pressure that exists in the whole level 2 system, by applying the percentage by volume ratio as follows:

L(Section @ OP(Full System) = V% x LP(Full System) and record on Table 2, Line 9.

12. Calculate the permissible leak rate for the test section at 2” w.g. by taking the ratio of the permissible leak rate of the section at the maximum system operation pressure, divided by the original equation used to determine the full system permissible leak rate at 2” w.g. as follows:

L2(Section) = L(Section@OP(Full System)) / 𝑶𝑷 𝑭𝒖𝒍𝒍 𝑺𝒚𝒔𝒕𝒆𝒎 𝟐"⁄ and record on Table 2, Line 10.

13. Calculate the final permissible leakage for the test section by correcting for the actual anticipated max operating pressure for the section using the following formula:

LP(Section) = L2(Section) x 𝑶𝑷 𝑺𝒆𝒄𝒕𝒊𝒐𝒏 𝟐"⁄ and record on Table 2, Line 11 and again on Table 4, Line 1.

14. Connect the pressurization source to the duct or housing which shall be capable of producing the specified positive or negative test pressure OP Section .

15. Connect the flowmeter or totalizing gas volume meter between the pressurization source and the housing (downstream of the throttling valve, if used).

16. Install temperature and pressure indicating devices so that they will indicate representative temperature and pressure inside the test section.

17. Seal test boundaries and close access doors in the normal manner. Temporary sealants, duct tape, or similar temporary materials SHALL NOT BE USED except for sealing the temporary blank-off panels.

18. Start the pressurization source and operate it until the pressure for OP Section is achieved. Maintain pressure constant with the flow control device within ±0.1 in. wg, until temperature equalizes (remains constant within ±0.5°F) for a minimum of 10 minutes.

19. Record in Table 3 of the Level 2 DALT record Sheet:

-Initial stabilized pressure, 𝑷𝒊 -Initial temperature of volume, 𝑻𝒊

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (revised 3/29/2021)

20. If using a flowmeter:

20.1 Measure the flow rate of the air being added to or removed from the duct or housing while maintaining pressure OP Section within ±0.1 in. wg. Record the flowrate at one minute intervals for a continuous 5 minute period in Table 3.

20.2. Complete Table 3:

20.2.1 Record in Table 3 of the Level 2 DALT record Sheet:

-Final test pressure, 𝑷𝒇

-Final temperature of volume, 𝑻𝒇

20.3 Using the equation, calculate and solve for the average measured leak rate, Lavg -Record on Table 4, Line 2

Lavg= 𝑭𝒍𝒐𝒘𝒓𝒂𝒕𝒆 @ 𝟏 𝒎𝒊𝒏 𝑭𝒍𝒐𝒘𝒓𝒂𝒕𝒆 @ 𝟐 𝒎𝒊𝒏 𝑭𝒍𝒐𝒘𝒓𝒂𝒕𝒆 @ 𝟑 𝒎𝒊𝒏 𝑭𝒍𝒐𝒘𝒓𝒂𝒕𝒆 @ 𝟒 𝒎𝒊𝒏 𝑭𝒍𝒐𝒘𝒓𝒂𝒕𝒆 @ 𝟓 𝒎𝒊𝒏

𝟓

20.4 Sign to validate that the information in Table 3 is complete and correct.

21. If using a totalizing gas volume meter:

21.1 Use the volume meter to totalize the volume of air being removed or added from the test section for a continuous 10 minute period and record the total volume from the meter in Table 3 in units of ft3.

21.2. Complete Table 3:

21.2.1 Record in Table 3 of the Level 2 DALT record Sheet:

-Final test pressure, 𝑷𝒇

-Final temperature of volume, 𝑻𝒇

21.3 Using the equation, calculate and solve for the average measured leak rate, Lavg -Record on Table 4, Line 2

Lavg = 𝑻𝒐𝒕𝒂𝒍 𝑽𝒐𝒍𝒖𝒎𝒆 𝒊𝒏 𝒄𝒖𝒃𝒊𝒄 𝒇𝒕 𝒅𝒖𝒓𝒊𝒏𝒈 𝒄𝒐𝒏𝒕𝒊𝒏𝒖𝒐𝒖𝒔 𝟏𝟎 𝒎𝒊𝒏𝒖𝒕𝒆 𝒑𝒆𝒓𝒊𝒐𝒅

𝟏𝟎 𝒎𝒊𝒏

21.4 Sign to validate that the information in Table 3 is complete and correct.

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (revised 3/29/2021)

22. Compare the calculated permissible leak rate LP Section to the measured average leak rate Lavg.

22.1 If Lavg is less than or equal to LP, circle PASS.

22.2 If Lavg is greater than LP Section , circle FAIL. See Step 24 of this procedure for leak location methods.

22.3 Sign to validate that the information in Table 4 is complete and correct.

23. Submit DALT Record sheet to the Government for review.

24. If the measured leak rate, Lavg , exceeds the calculated permissible leak rate, LP Section , locate leaks in accordance with one of the following techniques:

24.1. BUBBLE LEAK LOCATION METHOD (for positive pressure)

(a) Pressurize the test boundary to the maximum operating pressure for the system.

(b) With the test boundary under continuous pressure, apply bubble solution to areas to be tested.

Identify places where bubbles are found and perform corrective actions.

(c) Following corrective actions, retest in accordance with this test procedure.

24.2. AUDIBLE LEAK LOCATION METHOD:

(a) Pressurize the test boundary to the maximum operating pressure for the system.

(b) With the test boundary continuously pressurized, locate audible leaks (electronic sound detection equipment optional) and perform corrective actions.

(c) Following corrective actions, retest in accordance with this test procedure.

Note:

If a test assembly section fails as an assembly the assembly shall not be broken apart to be re-tested in smaller sections, but repaired and re-tested as the original assembly.

24.3 Following repairs, re-perform the leak test until satisfactory results are obtained.

Level 2 – Duct Air Leakage Test (DALT) Record – Constant Pressure Method ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (Revised 3/29/2021)

Date of test:

Pc. #(s) of Section tested:

Description of Section tested:

Test Attempt Number for this Section (Sequentially Numbered):

Note:

If a test assembly section fails as an assembly the assembly shall not be broken apart to be re-tested in smaller sections, but repaired and re-tested as the original assembly.

TABLE 1: INSTRUMENTATION INFORMATION

Pressure Gage/Meter Make, Model & Serial:

Pressure Gage/Meter Range:

Calibration Number: Accuracy:

Calibration Date: Calibration Due:

Flowmeter or Volume Totalizer Make, Model &

Serial:

Gage/Meter Range:

Orifice Plate: Orifice Plate Range:

Calibration Number: Accuracy:

Calibration Date: Calibration Due:

AirData Multimeter Make, Model & Serial:

Temperature Range

Calibration Number: Accuracy:

Calibration Date: Calibration Due:

Digital Temp Indicator Make, Model & Serial:

Temperature Range

Calibration Number: Accuracy:

Calibration Date: Calibration Due:

Instrument Information is Correct:

Technician Signature: ___________________________________ Date: _________________

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (Revised 3/29/2021)

Date of test:

Pc. #(s) of Section tested:

Description of Section tested:

Test Attempt Number for this Section (Sequentially Numbered):

Table 2: LEAK RATE CALCULATIONS

Source Line 1 Q(Full System) =

Line 2 OP(Full System) =

Line 3 L2(Full System) =

Line 4 LP(Full System) =

Line 5 V(Full System) =

Line 6 OP(Section) =

Line 7 V(Section) =

Line 8 V% = V(Section)/V(Full System) =

Line 9 L(Section @ OP(Full System)) = V% x LP(Full System) =

Line 10 L2(Section) = L(Section@OP(Full System)) / 𝑶𝑷 𝑭𝒖𝒍𝒍 𝑺𝒚𝒔𝒕𝒆𝒎 𝟐"⁄ =

Line 11 LP(Section) = L2(Section) x 𝑶𝑷 𝑺𝒆𝒄𝒕𝒊𝒐𝒏 𝟐"⁄ =

(if 𝑶𝑷 𝑺𝒆𝒄𝒕𝒊𝒐𝒏 = 𝑶𝑷 𝑭𝒖𝒍𝒍 𝑺𝒚𝒔𝒕𝒆𝒎 , then LP(Section) = L@OP(Full System))

Government Representative: ________________________________ Date:________________

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (Revised 3/29/2021)

Date of test:

Pc. #(s) of Section tested:

Description of Section tested:

Test Attempt Number for this Section (Sequentially Numbered):

TABLE 3: PRESSURE TEST RAW DATA

Initial Stabilized Pressure

(𝑷𝒊 "wg Final Stabilized Pressure (𝑷𝒇)

"wg:

Initial Volume Temp (𝑻𝒊 o F: Final Volume Temp (𝑻𝒇) oF:

If Using Flowmeter: (“N/A” Blocks if method not used) Flowrate at 1 min: cfm

Flowrate at 2 min: cfm

Flowrate at 3 min: cfm

Flowrate at 4 min: cfm

Flowrate at 5 min: cfm

Average Leak Rate: cfm

If Using Totalizing Gas Volume Meter: (“N/A” Blocks if method not used) Total Volume over 10 minute Period: ft3

Average Leak Rate: cfm

Technician Signature: _____________________________________ Date:________________

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (Revised 3/29/2021)

Date of test:

Pc. #(s) of Section tested:

Description of Section tested:

Test Attempt Number for this Section (Sequentially Numbered):

TABLE 4: LEAK RATE RESULT

Line 1 LP = Permissible Leak Rate at Test Pressure: CFM

Line 2 Lavg = Average Measured Leak Rate: CFM

Line 3

LEAK TEST RESULT: Is Lavg ≤ LP?

( PASS / FAIL ) circle one

Technician Signature: _____________________________________ Date:______________

Review of Data and Calculations:

A/E Representative Signature:________________________________Date:_____________

Shipyard Representative:____________________________________Date:______________

Level 4 – Duct Air Leakage Test (DALT) Procedure - Constant Pressure Method ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (Revised 3/29/2021)

Summary of Method:

The constant pressure method is useful for testing small volumes and is conducted at the maximum operating pressure for the system. All components that are part of the pressure boundary including ducting, fans, dampers, housings, flex connections, shaft seals and any other components forming the pressure boundary shall be tested to verify leak tightness. Temporary sealants, duct tape, or similar temporary materials SHALL NOT BE USED except for sealing the temporary blank-off panels. If the measured leak rate exceeds the permissible leak rate, the leaks shall be located by one of the methods listed in this procedure and repaired. The section shall then be retested per this procedure to verify leak-tightness.

NOTE:

This test procedure is written as if operating pressure is positive, but it would be identical for negative pressure systems with appropriate change in signs used in the data collection and calculations.

Pre-requisites:

Construction, modifications, and repairs affecting the test boundary shall be complete and the inlet and discharge openings of the section shall be sealed before the test is started. All electrical, piping, and instrument connections shall be complete and all permanent seals shall be installed before the test is started. The free air volume within the test boundary must be determined.

Test equipment:

(a) pressurization source capable of producing the specified positive or negative pressure

(b) covers to seal test boundaries

(c) clock or timer

(d) pressure-indicating device for test volume – (this procedure assumes pressure instrumentation reading in “inches of water” (“wg)).

(e) temperature-indicating device for test volume– (this procedure assumes a temperature indicating device reading in degrees Fahrenheit).

(f) bubble solution for detecting air leaks (bubble method)

(g) optional portable electronic sound detection equipment (audible leak method)

(h) flowmeter

(i) totalizing gas volume meter

Reference:

(a) ASME AG-1-2015; Article TA-III Duct and Housing Leak Test Procedural Guidelines; TA-III-

4100 CONSTANT PRESSURE TEST.

(b) DOE –HDBK-1169-2003; Table 5.6 – Recommended Maximum Permissible Leak rates at 2 in.wg Negative

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (Revised 3/29/2021)

Procedure:

1. Obtain a “Level 4 Duct Air Leakage Test (DALT) RECORD – “Constant Pressure Method” sheet.

2. Complete the header table for each sheet, (that each sheet may be traced to a unique testing event).

-Date of Test

-Pc# being tested* -Description of Section Tested -Test Attempt Number for this Section (Sequentially Numbered)

*Provide a marked up drawing identifying the Section, Pc #, and system boundaries of the test, and include as an Attachment to the Test Record Sheet.

3. Fill in the Table #1 Instrumentation Information for the Pressure Gage, Flowmeter, Thermometer; and sign that the information is correct.

4. The Government will complete Table 2 for “LEAK RATE CALCULATIONS” of the DALT Record Sheet.

-Maximum operating pressure (OPmax), in units inches-water (“wg). -Record on Table 2 Line 1 Use appropriate sign as applicable for positive (+) or negative (-) pressure systems.

-Volume (V) of Duct Section being Tested (cubic feet) -Record on Table 2 Line 2

5. Using the equation for L2 , for a Level 4 Test, the permissible leak rate at 2”wg, calculate L2 .

L2 = . 001 V -Record on Table 2 Line 3

6. Calculate the permissible leak rate at Test Pressure, LP, using maximum operating pressure OPmax from Table 2 Line 1.

LP=L2✓ OPmax /2 R - Record on Table 2 Line 4 and

‐ Record on Table 4 Line 1

This is the limit for allowable leakage for this section which will determine whether or not the measured leak rate is acceptable.

7. Connect the pressurization source to the duct or housing which shall be capable of producing the specified positive or negative test pressure (OPmax ).

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (Revised 3/29/2021)

8. Connect the flowmeter or totalizing gas volume meter between the pressurization source and the housing (downstream of the throttling valve, if used).

9. Install temperature and pressure indicating devices so that they will indicate representative temperature and pressure inside the test section.

10. Seal test boundaries and close access doors in the normal manner. Temporary sealants, duct tape, or similar temporary materials SHALL NOT BE USED except for sealing the temporary blank-off panels.

11. Start the pressurization source and operate it until the pressure for OPmax is achieved. Maintain pressure constant with the flow control device within ±0.1 in. wg, until temperature equalizes (remains constant within ±0.5°F) for a minimum of 10 minutes.

12. Record in Table 3 of the Level 4 DALT record Sheet:

-Initial stabilized pressure, Pi

-Initial temperature of volume, Ti

13. If using a flowmeter:

13.1 Measure the flow rate of the air being added to or removed from the duct or housing while maintaining pressure OPmax within ±0.1 in. wg. Record the flowrate at one minute intervals for a continuous 5 minute period in Table 3.

13.2. Complete Table 3:

13.2.1 Record in Table 3 of the Level 4 DALT record Sheet:

-Final test pressure, Pf

-Final temperature of volume, Tf

13.3 Using the equation, calculate and solve for the average measured leak rate Lavg .

-Record on Table 4, Line 2

Lavg= Flowrate @ 1 min Flowrate @ 2 min Flowrate @ 3 min Flowrate @ 4 min Flowrate @ 5 min

13.4 Sign to validate that the information in Table 3 is complete and correct.

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (Revised 3/29/2021)

14. If using a totalizing gas volume meter:

14.1 Use the volume meter to totalize the volume of air being removed or added from the test section for a continuous 10 minute period and record the total volume from the meter in Table 3 in units of ft3.

14.2. Complete Table 3:

14.2.1 Record in Table 3 of the Level 4 DALT record Sheet:

-Final test pressure, Pf

-Final temperature of volume, Tf

14.3. Using the equation, calculate and solve for the average measured leak rate Lavg .

-Record on Table 4, Line 2

Lavg = Total Volume in cubic ft during continuous 10 minute period

10 min

14.4 Sign to validate that the information in Table 3 is complete and correct.

15. Compare the calculated permissible leak rate LP to the measured average leak rate Lavg.

15.1 If Lavg is less than or equal to LP, circle PASS.

15.2 If Lavg is greater than LP, circle FAIL. See Step 17 of this procedure for leak location methods.

15.3 Sign to validate that the information in Table 4 is complete and correct.

16. Submit DALT Record sheet to the Government for review.

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4100 CONSTANT PRESSURE TEST. (Revised 3/29/2021)

17. If the average measured leak rate, Lavg , exceeds the calculated permissible leak rate, LP , locate leaks in accordance with one of the following techniques:

17.1. BUBBLE LEAK LOCATION METHOD: (Positive Pressure Only),

(a) Pressurize the test boundary to the maximum operating pressure for the system.

(b) With the test boundary under continuous pressure, apply bubble solution to areas to be tested.

Identify places where bubbles are found and perform corrective actions.

(c) Following corrective actions, retest in accordance with this test procedure.

17.2. AUDIBLE LEAK LOCATION METHOD:

(a) Pressurize the test boundary to the maximum operating pressure for the system.

(b) With the test boundary continuously pressurized, locate audible leaks (electronic sound detection equipment optional) and perform corrective actions.

(c) Following corrective actions, retest in accordance with this test procedure.

Note:

If a test assembly section fails as an assembly the assembly shall not be broken apart to be re-tested in smaller sections,

18. Following repairs re-perform the Leak test until satisfactory results are obtained.

Level 4 – Duct Air Leakage Test (DALT) Record – Constant Pressure Method (Revised 3/29/2021) ASME AG-1-2019; Article TA-III-4000 Procedural Guidelines; TA-III-4100 CONSTANT PRESSURE METHOD

Date of Test:

Pc. #(s) of Section Tested:

Description of Section Tested:

Test Attempt Number for this Section (Sequentially Numbered)

Note:

If a test assembly section fails as an assembly the assembly shall not be broken apart to be re-tested in smaller sections, but repaired and re-tested as the original assembly.

TABLE 1: INSTRUMENTATION INFORMATION

Pressure Gage/Meter Make, Model & Serial:

Pressure Gage/Meter Range:

Calibration Number: Accuracy:

Calibration Date: Calibration Due:

Flowmeter or Volume Totalizer Make, Model &

Serial:

Gage/Meter Range:

Orifice Plate: Orifice Plate Range:

Calibration Number: Accuracy:

Calibration Date: Calibration Due:

AirData Multimeter Make, Model & Serial:

Temperature Range

Calibration Number: Accuracy:

Calibration Date: Calibration Due:

Digital Temp Indicator Make, Model & Serial:

Temperature Range

Calibration Number: Accuracy:

Calibration Date: Calibration Due:

Technician Signature: _____ Date: ___ _

Date of Test:

Pc. #(s) of Section Tested:

Description of Section Tested:

Test Attempt Number for this Section (Sequentially Numbered)

TABLE 2: LEAK RATE CALCULATIONS

Source (Reference Document)

Line 1 OPmax =

Line 2 V =

Line 3 L2 =

Line 4 LP =

Government Representative: _______________________________Date: _______________

Date of Test:

Pc. #(s) of Section Tested:

Description of Section Tested:

Test Attempt Number for this Section (Sequentially Numbered)

TABLE 3: PRESSURE TEST RAW DATA

Initial Stabilized Pressure

(Pi “wg:

Final Stabilized Pressure

(Pf) "wg:

Initial Volume Temp (Ti) oF: Final Volume Temp (Tf) oF:

If Using Flowmeter: (“N/A” Blocks if method not used) Flowrate at 1 min: cfm

Flowrate at 2 min: cfm

Flowrate at 3 min: cfm

Flowrate at 4 min: cfm

Flowrate at 5 min: cfm

Average Leak Rate: cfm

If Using Totalizing Gas Volume Meter: (“N/A” Blocks if method not used) Total Volume over 10 minute Period: ft3

Average Leak Rate: cfm

Technician Signature: Date:

Date of Test:

Pc. #(s) of Section Tested:

Description of Section Tested:

Test Attempt Number for this Section (Sequentially Numbered)

TABLE 4: LEAK RATE RESULT

Line 1 LP = Permissible Leak Rate at Test Pressure: CFM

Line 2 Lavg = Average Measured Leak Rate: CFM

Line 3

LEAK TEST RESULT: Is Lavg ≤ LP?

( PASS / FAIL ) circle one

Technician Signature: _____________________________________ Date:_

Review of Data and Calculations:

A/E Representative Signature: Date:

Shipyard Representative: Date:

Level 4 – Duct Air Leakage Test (DALT) Procedure Pressure Decay Test Method (revised 3/29/2021)

Summary of Method:

The pressure decay method is useful for testing large volumes and is conducted by pressurizing to 1.25 times the maximum operating pressure, then allowing the pressure to decay for a fixed period of time, or until the pressure decreases to 75% of the maximum operating pressure, whichever occurs first. All components that are part of the pressure boundary including ducting, fans, dampers, housings, flex connections, shaft seals and any other components that are part of the pressure boundary shall be tested to verify leak tightness. Temporary sealants, duct tape, or similar temporary materials SHALL NOT BE USED except for sealing the temporary blank-off panels. If the measured leak rate exceeds the permissible leak rate, the leaks shall be located by one of the methods listed in this procedure and repaired. The section shall then be retested per this procedure to verify leak-tightness.

NOTE:

This test procedure is written as if operating pressure is positive, but it would be identical for negative pressure systems with appropriate change in signs used in the data collection and calculations.

Pre-requisites:

Construction, modifications, and repairs affecting the test boundary shall be complete and the inlet and discharge openings of the section shall be sealed before the test is started. All electrical, piping, and instrument connections shall be complete and all permanent seals shall be installed before the test is started. The following must be determined for the test section:

-Free air volume within the test boundary -Maximum operating pressure -Most restrictive structural capability pressure.

Test equipment:

(a) pressurization source capable of producing the specified positive or negative pressure

(b) covers to seal test boundaries

(c) clock or timer

(d) pressure-indicating device for test volume – (this procedure assumes pressure instrumentation reading in “inches of water” (“wg)).

(e) temperature-indicating device for test volume– (this procedure assumes a temperature indicating device reading in degrees Fahrenheit).

(f) bubble solution for detecting air leaks (bubble method)

(g) optional portable electronic sound detection equipment (audible leak method)

(h) barometer– (this procedure assumes pressure instrumentation reading in “inches of water” (“wg)).

Reference:

(a) ASME AG‐1‐2019; Article TA‐III Duct and Housing Leak Test Procedural Guidelines; TA‐III‐4200

PRESSURE DECAY TEST.

(b) DOE –HDBK‐1169‐2003; Table 5.6 – Recommended Maximum Permissible Leak rates at 2 in.wg Negative

Pressure Decay Test Method (revised 3/29/2021)

Procedure:

1. Obtain a “Level 4 Duct Air Leakage Test (DALT) RECORD –Pressure Decay Method” sheet.

2. Complete the header table for each sheet, (that each sheet may be traced to a unique testing event).

‐Date of Test

-Pc# being tested* -Description of Section Tested -Test Attempt Number for this Section (Sequentially Numbered)

*Provide a marked up drawing identifying the boundaries of the tested Section, and include as an Attachment to the Test Record Sheet.

3. Fill in the Table #1 Instrumentation Information for the Pressure Gage, Thermometer, and Barometer;

and sign that the information is correct.

4. The Government will complete Table 2: “LEAK RATE CALCULATIONS” of the DALT Record Sheet

-Maximum operating pressure (OPmax), in units inches-water (“wg). -Record on Table 2 Line 1 Use appropriate change in signs as applicable for positive (+) or negative (-) pressure systems.

-Most restrictive structural capability pressure (SCP), in units inches-water (“wg). -Record on Table 2 Line 2 Use appropriate sign as applicable for positive (+) or negative (-) pressure systems.

-Volume (V) of free air in Duct Section being Tested (cubic feet) -Record on Table 2 Line 3 -Record on Table 4

5. Using the equation for L2 , for a Level 4 Test, the permissible leak rate at 2”wg, calculate L2 .

𝑳𝟐 = . 𝟎𝟎𝟏 V -Record on Table 2 Line 4

6. Using the equation for P'i , calculate the initial test pressure.

Use appropriate sign as applicable for positive (+) or negative (-) pressure systems.

P'i = (1.25)(OPmax) -Record on Table 2 Line 5

7. Compare the |ABSOLUTE VALUES| of |P'i| to the |SCP| . Apply either Paragraph 7.1 or 7.2.

7.1 If |P'i | ≤ |SCP| , use the equation for P'f to calculate the final test pressure, P'f = (.75)(OPmax)

-Record on Table 2 Line 6 -Record “N/A” on Table 2 Line 7 -Record “N/A” on Table 2 Line 8

CAUTION

The test pressure (P'i ) shall not exceed the structural capability pressure (SCP ).

7.2 If | P'i | > |SCP |, use the equations to calculate modified final and initial test pressures, Pf modified and Pi modified , calculate them based on the OPmax (Table 2 Line 2) and SCP (Table 2 Line 3).

𝑷f modified = 0.8(OPmax) + [1.25(OPmax) – SCP] -Record on Table 2 Line 7

𝑷i modified = (OPmax - 𝑷i modified) + OPmax ‐Record on Table 2 Line 8

8. Calculate the permissible leak rate at Test Pressure, LP, using the permissible leak rate L2, (from Table 2 Line 4).

𝑳𝑷 = 𝑳𝟐 𝑶𝑷𝒎𝒂𝒙 𝟐⁄ ‐ Record on Table 2 Line 9 and

‐ Record on Table 5 Line 1

This is the limit for allowable leakage, LP, for this section which will determine whether or not the measured leak rate is acceptable.

9. Connect the pressurization source (with a leak-tight shutoff valve) and flow control device to the section of pressure boundary being tested, which must be capable of producing the specified positive or negative pressure.

10. Install temperature and pressure indicating devices so that they will indicate representative temperature and pressure inside the section being tested.

11. Seal test boundaries and close access doors in the normal manner. Temporary sealants, duct tape, or similar temporary materials SHALL NOT BE USED except for sealing the temporary blank‐off panels.

12. Start the pressurization source and operate it until achieving the initial test pressure:

𝑷 from: Table 2 Line 5 - OR-

𝑷 𝒊 𝒎𝒐𝒅𝒊𝒇𝒊𝒆𝒅 (if 𝑷 𝒊 > SCP ) Table 2 Line 8.

13. Maintain pressure constant with the flow control device within ±0.1 in. wg, until temperature equalizes (remains constant within ±0.5°F) for a minimum of 10 minutes.

14. Shut the shutoff valve.

15. Record in Table 3 of the Level 4 DALT record Sheet:

-Initial time, ( ti) -Initial test pressure, ( 𝑷𝒕𝒊) -Initial volume temperature, ( 𝑻𝒕𝒊) -Initial ambient barometric pressure

16. Record pressure readings on Table 3 in one minute intervals until pressure decays to the final test pressure 𝑷 𝒇 or 𝑷f modified (if 𝑷 𝒊 > SCP), or when 15 minutes expires, whichever happens first.

17. Upon completion of the test:

17.1 Record in Table 3 of the Level 4 DALT record Sheet:

-Final time, ( tf) -Final test pressure, ( 𝑷𝒕𝒇) -Final temperature of volume, ( 𝑻𝒕𝒇) -Final ambient barometric pressure

17.2 Sign to validate that the information in Table 3 is complete and correct.

Pressure Decay Test Method (revised 3/9/2021)

18. Calculate Average Measured Leak Rate, Lavg , as follows:

18.1 Perform unit conversion as required; use the “Calculation Worksheet” as necessary:

18.1.1 Calculate absolute initial and final test pressures by adding initial and final barometric pressure to the initial test pressure , Pti and final test pressure Ptf

Pressures were recorded in Table 3.:

Absolute Pressure = (Gage Pressure) + (Barometric Pressure)

𝑷𝒕𝒊 𝒂𝒃𝒔𝒐𝒍𝒖𝒕𝒆 = 𝑷𝒕𝒊 + Initial barometric pressure

𝑷𝒕𝒇 𝒂𝒃𝒔𝒐𝒍𝒖𝒕𝒆 = 𝑷𝒕𝒇 + Final barometric pressure

18.1.2 Convert inch of water (“wg) to pounds/square foot (lb/ft2).

1 “wg (inch of water) = 5.20 lb/ft2 ( pounds/square foot)

18.1.3 Convert °Fahrenheit to °Rankine

Temp(°Rankine) = Temp(°Fahrenheit) + 459.67

18.2 Record 𝑷𝒕𝒊 𝒂𝒃𝒔𝒐𝒍𝒖𝒕𝒆 , 𝑷𝒕𝒇 𝒂𝒃𝒔𝒐𝒍𝒖𝒕𝒆, Tti , Ttf, ti, and tf in units required, in Table 4.

18.3 Using the equation, calculate and solve for Lavg .

(Show calculations in space provided on Level 4 DALT Test Record Sheet.)

𝑻𝒕𝒊 Lavg = ( 𝑷𝒕𝒊 𝒂𝒃𝒔𝒐𝒍𝒖𝒕𝒆 − 𝑷𝒕𝒇 𝒂𝒃𝒔𝒐𝒍𝒖𝒕𝒆

𝑻𝒕𝒇

𝑽

𝑮𝒂𝒔𝑪𝒐𝒏𝒔𝒕𝒂𝒏𝒕∗ 𝒕𝒇 𝒕𝒊 ∗𝟎.𝟎𝟕𝟓

Where GasConstant 53.35 ft-lb/ lb oR

18.4 Record the calculated Lavg in Table 5 Line 2.

19. Compare the calculated permissible leak rate LP to the measured average leak rate Lavg.

19.1 If Lavg is less than or equal to LP, circle PASS.

19.2 If Lavg is greater than LP, circle FAIL. See Step 21 of this procedure for leak location methods.

19.3 Sign to validate that the information in Table 5 is complete and correct.

20. Submit DALT Record sheet to the Government for review.

21. If the measured leak rate, Lavg , exceeds the calculated permissible leak rate, LP , locate leaks in accordance with one of the following techniques:

21.1. BUBBLE LEAK LOCATION METHOD: (Positive pressure Only).

(a) Pressurize the test boundary to the maximum operating pressure for the system.

(b) With the test boundary under continuous pressure, apply bubble solution to areas to be tested.

Identify places where bubbles are found and perform corrective actions.

(c) Following corrective actions, retest in accordance with this test procedure.

21.2. AUDIBLE LEAK LOCATION METHOD:

(a) Pressurize the test boundary to the maximum operating pressure for the system.

(b) With the test boundary continuously pressurized, locate audible leaks (electronic sound detection equipment optional) and perform corrective actions.

(c) Following corrective actions, retest in accordance with this test procedure.

Note:

If a test assembly section fails as an assembly the assembly shall not be broken apart to be re-tested in smaller sections, but repaired and re-tested as the original assembly.

22. Following repairs obtain new DALT Record Sheet, update the test attempt number with next sequential # and re-perform the Leak test until satisfactory results are obtained.

Level 4 – Duct Air Leakage Test (DALT) Record - Pressure Decay Method ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4200 PRESSURE DECAY TEST. (Revised 3/29/2021)

Date of test:

Pc. #(s) of Section tested:

Description of Section tested:

Test Attempt Number for this Section (Sequentially Numbered):

Note:

If a test assembly section fails as an assembly the assembly shall not be broken apart to be re-tested in smaller sections, but repaired and re-tested as the original assembly.

TABLE 1: INSTRUMENTATION INFORMATION

Pressure Gage/Meter Make, Model & Serial:

Pressure Gage/Meter Range:

Calibration Number: Accuracy:

Calibration Date: Calibration Due:

Thermometer Make, Model & Serial:

Temperature Range

°F

Calibration Number: Accuracy: °F Calibration Date: Calibration Due:

AirData Multimeter Make, Model & Serial:

Temperature Range °F

Calibration Number: Accuracy: °F

Calibration Date: Calibration Due:

Barometer Make, Model & Serial:

Automated Terminal Info System (ATIS) at Portsmouth International

Airport (KPSM 603-334-6070)

Barometer Range: N/A

Calibration Number: N/A Accuracy: N/A

Calibration Date: N/A Calibration Due: N/A

Technician Signature: ___________________________________ Date: ________________

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4200 PRESSURE DECAY TEST. (Revised 3/29/2021)

Date of test:

Pc. #(s) of Section tested:

Description of Section tested:

Test Attempt Number for this Section (Sequentially Numbered):

TABLE 2: LEAK RATE CALCULATIONS

Source

Line 1 OPmax = ” wg

Line 2 SCP = ” wg

Line 3 V= ft3

Line 4 L2 = cfm

Line 5 P'i = ” wg

Line 6 P'f = ” wg

Line 7 𝑷f modified = ” wg

Line 8 𝑷i modified = ” wg

Line 9 LP = cfm

Government Representative:____________________________________Date:______________

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4200 PRESSURE DECAY TEST. (Revised 3/29/2021)

Date of test:

Pc. #(s) of Section tested:

Description of Section tested:

Test Attempt Number for this Section (Sequentially Numbered):

TABLE 3: PRESSURE DECAY RAW DATA

Initial Time (𝒕𝒊 : Final Time (𝒕𝒇 :

Initial Test Pressure (𝑷𝒕𝒊 "wg:

Final Test Pressure (𝑷𝒕𝒇) "wg:

Initial Volume Temp (𝑻𝒕𝒊 o F: Final Volume Temp (𝑻𝒕𝒇) oF:

Initial barometric pressure "wg: Final barometric pressure "wg:

Note: Terminate test when internal pressure decays to P'f or 𝑷f , or when 15 minutes expires, whichever comes first.

Reading 1: "wg

Reading 6: "wg Reading 11: "wg

Reading 2: "wg Reading 7: "wg Reading 12: "wg

Reading 3: "wg Reading 8: "wg Reading 13: "wg

Reading 4: "wg Reading 9: "wg Reading 14: "wg

Reading 5: "wg Reading 10: "wg Reading 15: "wg

(“N/A” unused Blocks)

Technician Signature: _____________________________________ Date:__________

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4200 PRESSURE DECAY TEST. (Revised 3/29/2021)

Date of test:

Pc. #(s) of Section tested:

Description of Section tested:

Test Attempt Number for this Section (Sequentially Numbered):

Unit Conversion Worksheet

Absolute Pressure = (Gage Pressure) + (Initial Barometric Pressure)

Pressure pounds per square foot (lb/ft2) =

5.20 lb/ft2 X

1 “wg

Pressure in Inches of water (“wg)

Temp(°Rankine) = 459.67 + Temp(°Fahrenheit)

(“N/A” unused Blocks)

TABLE 4: MEASURED AVERAGE LEAK RATE , Lavg, EQUATION CALCULATION DATA

Variable Value Units (IP) Description

V ft3 Volume within Test Boundary

𝑷𝒕𝒊 𝒂𝒃𝒔𝒐𝒍𝒖𝒕𝒆 lb/ft2 Absolute (Gage) + (Initial Barometric Pressure)

Initial Pressure at Start of Test

𝑷𝒕𝒇 𝒂𝒃𝒔𝒐𝒍𝒖𝒕𝒆 lb/ft2 Absolute (Gage) + (Final Barometric Pressure)

Final Pressure at End of Test

𝑻𝒕𝒊 °Rankine (°R) Absolute Temperature at Start of Test

𝑻𝒕𝒇 °Rankine (°R) Absolute Temperature at End of Test 𝒕𝒊 minutes Time at Start of Test 𝒕𝒇 minutes Time at End of Test

GasConstant 53.35 ft-lb/lb°R Gas Constant for Air=53.35 ft-lb/lb°R

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4200 PRESSURE DECAY TEST. (Revised 3/29/2021)

Date of test:

Pc. #(s) of Section tested:

Description of Section tested:

Test Attempt Number for this Section (Sequentially Numbered):

Average Measured Leak Rate Equation Calculation Worksheet:

Lavg = ( 𝑷𝒕𝒊 𝒂𝒃𝒔

𝑻𝒕𝒊

𝑷𝒕𝒇 𝒂𝒃𝒔

𝑻𝒕𝒇

𝑽

𝑮𝒂𝒔𝑪𝒐𝒏𝒔𝒕𝒂𝒏𝒕∗ 𝒕𝒇 𝒕𝒊 ∗𝟎.𝟎𝟕𝟓

ASME AG‐1‐2019; Article TA‐III‐4000 Procedural Guidelines; TA‐III‐4200 PRESSURE DECAY TEST. (Revised 3/29/2021)

Date of test:

Pc. #(s) of Section tested:

Description of Section tested:

Test Attempt Number for this Section (Sequentially Numbered):

TABLE 5: LEAK RATE RESULT

Line 1 LP = Permissible Leak Rate at Test Pressure: CFM

Line 2 Lavg = Average Measured Leak Rate:

(Provide the absolute value)

CFM

Line 3

LEAK TEST RESULT: Is Lavg ≤ LP?

( PASS / FAIL ) circle one

Technician Signature: _____________________________________ Date:__________

Review of Data and Calculations:

A/E Representative Signature:________________________________Date:__________

Shipyard Representative:____________________________________Date:__________

SMACNA – Duct Air Leakage Test (DALT) Procedure Surface Area Approach

HVAC Air Duct Leakage Test Manual – Sheet Metal and Air Conditioning Contractors’ National Associates Inc. (SMACNA)

Summary of Method:

The SMACNA procedure was published for leakage testing of low, medium and high pressure ductwork.

The test uses the surface area of the duct and pressure in the duct as the basic parameters. All components that are part of the pressure boundary including ducting, fans, dampers, housings, flex connections, shaft seals and any other components forming the pressure boundary shall be tested to verify leak tightness. Temporary sealants, duct tape, or similar temporary materials SHALL NOT BE USED except for sealing the temporary blank-off panels. If the measured leak rate exceeds the permissible leak rate, the leaks shall be located by one of the methods listed in this procedure and repaired. The section shall then be retested per this procedure to verify leak-tightness.

NOTE:

This test procedure is written as if operating pressure is positive, but it would be identical for negative pressure systems with appropriate change in signs used in the data collection and calculations.

Pre-requisites:

Construction, modifications, and repairs affecting the test boundary shall be complete and comply with the contract documents. The inlet and discharge openings of the section shall be sealed before the test is started. All electrical, piping, and instrument connections shall be complete and all permanent seals shall be installed before the test is started.

Test equipment:

(a) pressurization source capable of producing the specified positive or negative pressure

(b) covers to seal test boundaries

(c) pressure-indicating device for test volume – (this procedure assumes pressure instrumentation reading in “inches of water” (“wg)).

(d) temperature-indicating device for test volume– (this procedure assumes a temperature indicating device reading in degrees Fahrenheit).

(e) optional bubble solution for detecting air leaks (bubble method)

(f) optional portable electronic sound detection equipment (audible leak method)

(g) barometer– (this procedure assumes pressure instrumentation reading in “inches of water” (“wg)).

(h) flowmeter

(i) totalizing gas volume meter

Reference:

(a) HVAC Air Duct Leakage Test Manual – Sheet Metal and Air Conditioning Contractors’ National Associates Inc. (SMACNA) 7th Printing – January 2003

HVAC Air Duct Leakage Test Manual – Sheet Metal and Air Conditioning Contractors’ National

Procedure:

1. Obtain a “SMACNA Duct Air Leakage Test (DALT) Record –“Surface Area Method” sheet.

2. Complete the header table for each sheet, (that each sheet may be traced to a unique testing event).

-Date of Test -Section I.D. # being tested * -Description of Section Tested -Test Attempt Number for this Section (Sequentially Numbered)

3. Fill in the Table #1 Instrumentation Information for the Pressure Gage, Flowmeter, Thermometer, and Barometer; and sign that the information is correct.

4. The A&E firm will complete Table 2 for “LEAK RATE CALCULATIONS” of the DALT Record Sheet.

-Seal class ductwork to be tested -Record on Table 2 Line 1

-Leak class for rectangular ductwork , to be tested -Record on Table 2 Line 2

-Leak class for round ductwork , to be tested -Record on Table 2 Line 3

-Test pressure ( ), in units inches-water (“wg). -Record on Table 2 Line 4 Use appropriate sign as applicable for positive (+) or negative (-) pressure systems.

5. Using the equation for surface area of a section of rectangular ductwork, do the following calculations:

5.1 For duct sections:

Perimeter (P) = (2 x Width(W)) + (2 x Height(H)) Surface Area (SA) = P x Length(L),

5.2 For duct caps

Surface Area (SACAP) = Width(W) x Height(H)

Show calculations in Table 3..

-Record total surface area of rectangular ductwork ( ), on Table 2 Line 5

6 Using the equation for surface area of a section of round ductwork, do the following calculations:..

6.1 For duct sections:

Perimeter (P) = 2 x Pi x Radius(R) Surface Area (SA) = P x Length(L),

6.2 For duct caps

Surface Area (SACAP) = Pi x Radius(R)2

Show calculations in Table 3..

-Record total surface area of round ductwork ( ), on Table 2 Line 6

HVAC Air Duct Leakage Test Manual – Sheet Metal and Air Conditioning Contractors’ National Associates Inc. (SMACNA)

7. Calculate the permissible leak rate at Test Pressure, using the SMACNA method in the SMACNA Manual Appendix E: (F = CL x PT

0.65 x SA)/100.

= x 0.65 x / 100 Record on Table 2 Line 7 = x 0.65 x / 100 Record on Table 2 Line 8

= + - Record on Table 2 Line 9 and

- Record on Table 5 Line 1

This is the limit for allowable leakage for this section which will determine whether or not the measured leak rate is acceptable.

.1 A&E representative sign entry indicating that data entered in table 2 has been reviewed and is complete and correct.

Prior to actual testing it is recommended that the Shipyard concur with the data recorded in table 2.

8. Connect the pressurization source to the duct or housing which shall be capable of producing the specified positive or negative test pressure ( ).

9. Connect the flowmeter or totalizing gas volume meter between the pressurization source and the housing (downstream of the throttling valve, if used).

10. Install temperature and pressure indicating devices so that they will indicate representative temperature and pressure inside the test section.

11. Seal test boundaries and close access doors in the normal manner. Temporary sealants, duct tape, or similar temporary materials SHALL NOT BE USED except for sealing the temporary blank-off panels.

12. Start the pressurization source and operate it until the pressure for is achieved. Maintain pressure constant with the flow control device within ±0.1 in. wg, until temperature equalizes (remains constant within ±0.5°F) for a minimum of 10 minutes.

13. Record in Table 4 of the Level 2 DALT record Sheet:

-Initial stabilized pressure, -Initial temperature of volume, -Initial ambient barometric pressure

14. If using a flowmeter:

HVAC Air Duct Leakage Test Manual – Sheet Metal and Air Conditioning Contractors’ National

14.1 Measure the flow rate of the air being added to or removed from the duct or housing while maintaining pressure within ±0.1 in. wg. Record the flowrate at one minute intervals for a continuous 5 minute period in Table 3.

14.2. Complete Table 4:

14.2.1 Record in Table 4 of the Level 2 DALT record Sheet:

-Final test pressure, -Final temperature of volume, -Final ambient barometric pressure

14.3 Using the equation, calculate and solve for the average measured leak rate, -Record on Table 5, Line 2( @ @ @ @ @ )

14.4 Sign to validate that the information in Table 4 is complete and correct.

HVAC Air Duct Leakage Test Manual – Sheet Metal and Air Conditioning Contractors’ National

15. If using a totalizing gas volume meter:

15.1 Use the volume meter to totalize the volume of air being removed or added from the test section for a continuous 10 minute period and record the total volume from the meter in Table 4 in units of ft3.

15.2. Complete Table 4:

15.2.1 Record in Table 4 of the Level 2 DALT record Sheet:

-Final test pressure, -Final temperature of volume, -Final ambient barometric pressure

15.3 Using the equation, calculate and solve for the average measured leak rate, -Record on Table 5, Line 2

15.4 Sign to validate that the information in Table 4 is complete and correct.

16. Compare the calculated permissible leak rate to the measured average leak rate .

16.1 If is less than or equal to , circle PASS.

16.2 If is greater than LP, circle FAIL. See Step 18 of this procedure for leak location methods.

16.3 Sign to validate that the information in Table 5 is complete and correct.

17. Submit DALT Record sheet for concurrence by the Shipyard.

HVAC Air Duct Leakage Test Manual – Sheet Metal and Air Conditioning Contractors’ National

18. If the measured leak rate, , exceeds the calculated permissible leak rate, , locate leaks in accordance with one of the following techniques:

18.1. BUBBLE LEAK LOCATION METHOD (Positive Pressure)

(a) Pressurize the test boundary to the maximum operating pressure for the system.

(b) With the test boundary under continuous pressure, apply bubble solution to areas to be tested.

Identify places where bubbles are found and perform corrective actions.

(c) Following corrective actions, retest in accordance with this test procedure.

18.2. AUDIBLE LEAK LOCATION METHOD:

(a) Pressurize the test boundary to the maximum operating pressure for the system.

(b) With the test boundary continuously pressurized, locate audible leaks (electronic sound detection equipment optional) and perform corrective actions.

(c) Following corrective actions, retest in accordance with this test procedure.

Note:

If a test assembly section fails as an assembly the assembly shall be broken apart to be re-tested in smaller sections,

19. Following repairs re-perform the Leak test until satisfactory results are obtained.

SMACNA – Duct Air Leakage Test (DALT) Record – Surface Area Method HVAC Air Duct Leakage Test Manual - SMACNA SURFACE AREA METHOD.

Date of test:

Pc. #(s) of Section tested:

Description of Section tested:

Test Attempt Number for this Section (Sequentially Numbered):

Note:

If a test assembly section fails as an assembly the assembly shall not be broken apart to be re-tested in smaller sections, TABLE 1: INSTRUMENTATION INFORMATION

Pressure Gage/Meter Make, Model & Serial:

Pressure Gage/Meter Range:

” wg

Calibration Number: Precision: ” wg Calibration Date: Calibration Due:

Flowmeter or Volume Totalizer Make, Model &

Serial:

Gage/Meter Range: cfm or ft3

Calibration Number: Precision:

Thermometer Make, Model & Serial:

Temperature Range

°F

Calibration Number: Precision: °F

Barometer Make, Model & Serial:

Barometer Range: ” wg

Calibration Number: Precision: ” wg

NOTE 1: Barometric pressure shall be obtained from Automated Terminal Info System (ATIS) at Portsmouth International Airport (KPMS 603-334-6070)

Description of Section tested:

TABLE 2: LEAK RATE CALCULATIONS

Source (Reference Document)

Line 1 Seal Class = SMACNA. Manual Table 1-2

Line 2 Leak Class

(Rectangular) (CLRe) =

SMACNA. Manual Table 4-1

Line 3 Leak Class (Round) (CLRo) =

SMACNA. Manual Table 4-1

Line 4 PT = ” wg SMACNA. Manual Table 1-2

Line 5 SARe

(Rectangular)= ft2 Table 3 Surface Area

Calculations, based on SMACNA Procedure Sheet line 5

Line 6 SARo (Round)= ft2 Table 3 Surface Area Calculations, based on SMACNA

Procedure Sheet line 6 Line 7 FRe =

(12 x 30.65x 1085.0) /100 cfm SMACNA Procedure Sheet line 7

Line 8 FRo = (6 x 30.65 x 0) /100 cfm SMACNA Procedure Sheet line 7

Line 9 F =

265.91 + 0 cfm SMACNA Procedure Sheet line 7

A/E Representative Signature: _Date: _

Shipyard Representative Concur: _Date:

Description of Section tested:

Table 3 Duct Section Surface Area (SA) Calculation Worksheet:

Rectangular Duct Sections Section

ID

number

Plan showing section & ID number

Duct Height (H)

Duct Width (W)

Duct Perimeter (P

= 2H + 2W)

Length of Duct Section

(L)

Surface Area of Duct Section (SA = P x L) or SAcap = H x W

1 Cap ft ft ft2 ft ft2

2 ft ft ft2 ft ft2

3 ft ft ft2 ft ft2

4 (Riser) ft ft ft2 ft ft2

5 ft ft ft2 ft ft2

6 ft ft ft2 ft ft2

8 Cap ft ft ft2 ft ft2

Total Surface Area of Rectangular Duct (SARe) = ft2

Round Duct Sections…