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LEED v4.1
New Construction
Indoor Environmental Quality
Indoor Air Quality Assessment

LEED CREDIT

NC-v4.1 EQc4: Indoor air quality assessment 1-2 points

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© Copyright U.S. Green Building Council, Inc. All rights reserved.

Intent

To establish better quality indoor air in the building after construction and during occupancy to protect human health, productivity, and wellbeing.

Requirements

Select one of the following two options, to be implemented after construction ends and the building has been completely cleaned. All interior finishes, such as millwork, doors, paint, carpet, acoustic tiles, and movable furnishings (e.g., workstations, partitions), must be installed, and major VOC punch list items must be finished. The options cannot be combined.

Option 1. Flush-Out (1 point)
Path 1. Before Occupancy
Install new filtration media and perform a building flush-out by supplying a total air volume of 14,000 cubic feet of outdoor air per square foot (4 267 140 liters of outdoor air per square meter) of gross floor area while maintaining an internal temperature of at least 60°F (15°C) and no higher than 80°F (27°C) and relative humidity no higher than 60%. OR
Path 2. During Occupancy
If occupancy is desired before the flush-out is completed, the space may be occupied only after delivery of a minimum of 3,500 cubic feet of outdoor air per square foot (1 066 260 liters of outdoor air per square meter) of gross floor area while maintaining an internal temperature of at least 60°F (15°C) and no higher than 80°F (27°C) and relative humidity no higher than 60%. Once the space is occupied, it must be ventilated at a minimum rate of 0.30 cubic foot per minute (cfm) per square foot of outdoor air (1.5 liters per second per square meter of outside air) or the design minimum outdoor air rate determined in EQ Prerequisite Minimum Indoor Air Quality Performance, whichever is greater. During each day of the flush-out period, ventilation must begin at least three hours before occupancy and continue during occupancy. These conditions must be maintained until a total of 14,000 cubic feet per square foot of outdoor air (4 270 liters of outdoor air per square meter) has been delivered to the space. OR
Option 2. Air Testing (1-2 points)
After construction ends and before occupancy, but under ventilation conditions typical for occupancy, conduct baseline IAQ testing in occupied spaces for the contaminants listed in Path 1. Particulate matter and inorganic gases (for 1 point) and/or Path 2. Volatile organic compounds (for 1 point). Retail projects may conduct the testing within 14 days of occupancy.
Path 1. Particulate Matter and Inorganic Gases (1 point)
Test for the particulate matter (PM) and inorganic gases listed in Table 1, using an allowed test method, and demonstrate the contaminants do not exceed the concentration limits listed in the table.
Table 1. Particulate Matter and inorganic gases
Contaminant (CAS#) Concentration Limit (µg/m3) Allowed Test Methods
Carbon monoxide (CO) 9 ppm; no more than 2 ppm above outdoor levels ISO 4224
EPA Compendium Method IP-3
GB/T 18883-2002 for projects in China

Direct calibrated electrochemical instrument with accuracy of (+/- 3% of reading and resolution of 0.1 ppm).

NDIR CO Sensors with accuracy of 1% of 10 ppm full scale and display resolution of less than 0.1ppm
PM 10 ISO 14644-1:2015, cleanroom class of 8 or lower 50 μg/m3 Healthcare only: 20 μg/m3 Particulate monitoring device with accuracy greater of 5 micrograms/m3 or 20% of reading and resolution (5 min average data) +/- 5 µg/m3
PM 2.5 12 μg/m3 or 35 µg/m3**
Ozone 0.07 ppm Monitoring device with accuracy greater of 5 ppb or 20% of reading and resolution (5 min average data) +/- 5 ppb ISO 13964 ASTM D5149 -– 02 EPA designated methods for Ozone

**Projects in areas with high ambient levels of PM2.5 (known EPA nonattainment areas for PM2.5, or local equivalent) must meet the 35 ug/m3 limit, all other projects should meet the 12 ug/m3 limit.

AND/OR
Path 2. Volatile Organic Compounds (1 point)
Perform a screening test for Total Volatile Organic Compounds (TVOC). Use ISO 16000-6, EPA TO-17, or EPA TO-15 to collect and analyze the air sample. Calculate the TVOC value per EN 16516:2017, CDPH Standard Method v1.2 2017 section 3.9.4, or alternative calculation method as long as full method description is included in test report. If the TVOC levels exceed 500 µg/m3, investigate for potential issues by comparing the individual VOC levels from the GC/MS results to associated cognizant authority health-based limits. Correct any identified issues and re-test if necessary. Additionally, test for the individual volatile organic compounds listed in Table 2 using an allowed test method and demonstrate the contaminants do not exceed the concentration limits listed in the table. Laboratories that conduct the tests must be accredited under ISO/IEC 17025 for the test methods they use. Exemplary performance is available for projects that test for the additional target volatile organic compounds specified in CDPH Standard Method v1.2-2017, Table 4-1 and do not exceed the full CREL levels for these compounds adopted by Cal/EPA OEHHA in effect on June 2016.
Table 2. Volatile organic compounds
Contaminant (CAS#) Concentration Limit (µg/m3) Allowed Test Methods
Formaldehyde 50-00-0 20 µg/m3 (16 ppb) ISO 16000-3, 4; EPA TO-11a, EPA comp. IP-6 ASTM D5197-16
Acetaldehyde 75-07-0 140 µg/m3
Benzene 71-43-2 3 µg/m3 ISO 16000-6 EPA IP-1, EPA TO-17, EPA TO-15 ISO 16017-1, 2; ASTM D6196-15
Hexane (n-) 110-54-3 7000 µg/m3
Naphthalene 91-20-3 9 µg/m3
Phenol 108-95-2 200 µg/m3
Styrene 100-42-5 900 µg/m3
Tetrachloroethylene 127-18-4 35 µg/m3
Toluene 108-88-3 300 µg/m3
Vinyl acetate 108-05-4 200 µg/m3
Dichlorobenzene (1,4-) 106-46-7 800 µg/m3
Xylenes-total 108-38-3, 95-47-6, and 106-42-3 700 µg/m3
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Addenda

4/9/2021Updated: 4/19/2021
Rating System Correction
Description of change:
Revise credit intent to: "To establish better quality indoor air in the building after construction and during occupancy to protect human health, productivity, and wellbeing."
Campus Applicable
No
Internationally Applicable:
No
11/9/2020Updated: 3/1/2021
Rating System Correction
Description of change:
Under Table 1, allowed test methods column, row 1 for carbon monoxide, Replace the accuracy for direct calibrated electrochemical instruments with "+/- 3% of reading and resolution of 0.1 ppm. NDIR CO Sensors with accuracy of 1% of 10 ppm full scale and display resolution of less than 0.1ppm"
Campus Applicable
No
Internationally Applicable:
No
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USGBC logo

© Copyright U.S. Green Building Council, Inc. All rights reserved.

Intent

To establish better quality indoor air in the building after construction and during occupancy to protect human health, productivity, and wellbeing.

Requirements

Select one of the following two options, to be implemented after construction ends and the building has been completely cleaned. All interior finishes, such as millwork, doors, paint, carpet, acoustic tiles, and movable furnishings (e.g., workstations, partitions), must be installed, and major VOC punch list items must be finished. The options cannot be combined.

Option 1. Flush-Out (1 point)
Path 1. Before Occupancy
Install new filtration media and perform a building flush-out by supplying a total air volume of 14,000 cubic feet of outdoor air per square foot (4 267 140 liters of outdoor air per square meter) of gross floor area while maintaining an internal temperature of at least 60°F (15°C) and no higher than 80°F (27°C) and relative humidity no higher than 60%. OR
Path 2. During Occupancy
If occupancy is desired before the flush-out is completed, the space may be occupied only after delivery of a minimum of 3,500 cubic feet of outdoor air per square foot (1 066 260 liters of outdoor air per square meter) of gross floor area while maintaining an internal temperature of at least 60°F (15°C) and no higher than 80°F (27°C) and relative humidity no higher than 60%. Once the space is occupied, it must be ventilated at a minimum rate of 0.30 cubic foot per minute (cfm) per square foot of outdoor air (1.5 liters per second per square meter of outside air) or the design minimum outdoor air rate determined in EQ Prerequisite Minimum Indoor Air Quality Performance, whichever is greater. During each day of the flush-out period, ventilation must begin at least three hours before occupancy and continue during occupancy. These conditions must be maintained until a total of 14,000 cubic feet per square foot of outdoor air (4 270 liters of outdoor air per square meter) has been delivered to the space. OR
Option 2. Air Testing (1-2 points)
After construction ends and before occupancy, but under ventilation conditions typical for occupancy, conduct baseline IAQ testing in occupied spaces for the contaminants listed in Path 1. Particulate matter and inorganic gases (for 1 point) and/or Path 2. Volatile organic compounds (for 1 point). Retail projects may conduct the testing within 14 days of occupancy.
Path 1. Particulate Matter and Inorganic Gases (1 point)
Test for the particulate matter (PM) and inorganic gases listed in Table 1, using an allowed test method, and demonstrate the contaminants do not exceed the concentration limits listed in the table.
Table 1. Particulate Matter and inorganic gases
Contaminant (CAS#) Concentration Limit (µg/m3) Allowed Test Methods
Carbon monoxide (CO) 9 ppm; no more than 2 ppm above outdoor levels ISO 4224
EPA Compendium Method IP-3
GB/T 18883-2002 for projects in China

Direct calibrated electrochemical instrument with accuracy of (+/- 3% of reading and resolution of 0.1 ppm).

NDIR CO Sensors with accuracy of 1% of 10 ppm full scale and display resolution of less than 0.1ppm
PM 10 ISO 14644-1:2015, cleanroom class of 8 or lower 50 μg/m3 Healthcare only: 20 μg/m3 Particulate monitoring device with accuracy greater of 5 micrograms/m3 or 20% of reading and resolution (5 min average data) +/- 5 µg/m3
PM 2.5 12 μg/m3 or 35 µg/m3**
Ozone 0.07 ppm Monitoring device with accuracy greater of 5 ppb or 20% of reading and resolution (5 min average data) +/- 5 ppb ISO 13964 ASTM D5149 -– 02 EPA designated methods for Ozone

**Projects in areas with high ambient levels of PM2.5 (known EPA nonattainment areas for PM2.5, or local equivalent) must meet the 35 ug/m3 limit, all other projects should meet the 12 ug/m3 limit.

AND/OR
Path 2. Volatile Organic Compounds (1 point)
Perform a screening test for Total Volatile Organic Compounds (TVOC). Use ISO 16000-6, EPA TO-17, or EPA TO-15 to collect and analyze the air sample. Calculate the TVOC value per EN 16516:2017, CDPH Standard Method v1.2 2017 section 3.9.4, or alternative calculation method as long as full method description is included in test report. If the TVOC levels exceed 500 µg/m3, investigate for potential issues by comparing the individual VOC levels from the GC/MS results to associated cognizant authority health-based limits. Correct any identified issues and re-test if necessary. Additionally, test for the individual volatile organic compounds listed in Table 2 using an allowed test method and demonstrate the contaminants do not exceed the concentration limits listed in the table. Laboratories that conduct the tests must be accredited under ISO/IEC 17025 for the test methods they use. Exemplary performance is available for projects that test for the additional target volatile organic compounds specified in CDPH Standard Method v1.2-2017, Table 4-1 and do not exceed the full CREL levels for these compounds adopted by Cal/EPA OEHHA in effect on June 2016.
Table 2. Volatile organic compounds
Contaminant (CAS#) Concentration Limit (µg/m3) Allowed Test Methods
Formaldehyde 50-00-0 20 µg/m3 (16 ppb) ISO 16000-3, 4; EPA TO-11a, EPA comp. IP-6 ASTM D5197-16
Acetaldehyde 75-07-0 140 µg/m3
Benzene 71-43-2 3 µg/m3 ISO 16000-6 EPA IP-1, EPA TO-17, EPA TO-15 ISO 16017-1, 2; ASTM D6196-15
Hexane (n-) 110-54-3 7000 µg/m3
Naphthalene 91-20-3 9 µg/m3
Phenol 108-95-2 200 µg/m3
Styrene 100-42-5 900 µg/m3
Tetrachloroethylene 127-18-4 35 µg/m3
Toluene 108-88-3 300 µg/m3
Vinyl acetate 108-05-4 200 µg/m3
Dichlorobenzene (1,4-) 106-46-7 800 µg/m3
Xylenes-total 108-38-3, 95-47-6, and 106-42-3 700 µg/m3

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