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  2. Air quality standards

Air quality standards

Features>Air>01. Air quality standards

01. Air quality standards

Intent: 

To ensure a basic level of high indoor air quality.

Post Date: 27 Apr, 2017
Status: Approved

Updated (Approved.)
Projects may exceed 500 µg/m³ in total VOCs (part 1c), so long as the following individual component VOCs do not exceed the limits listed in CDPH/EHLB/Standard Method V1.1, Table 4.1 (one half the Chronic Reference Exposure Levels (CREL) issued by Office of Environmental Health Hazard Assessment):

Compound Name CAS No. Allowable Conc (µg/m³)
Benzene 71-43-2 30
Carbon disulfide 75-15-0 400
Carbon tetrachloride 56-23-5 20
Chlorobenzene 108-90-7 500
Chloroform 67-66-3 150
Dichlorobenzene (1,4-) 106-46-7 400
Dichloroethylene (1,1) 75-35-4 35
Ethylbenzene 100-41-4 1000
Hexane (n-) 110-54-3 3500
Isopropyl Alcohol 67-63-0 3500
Methyl chloroform 71-55-6 500
Methylene chloride 75-09-2 200
Methyl tert-butyl ether 1634-04-4 4000
Styrene 100-42-5 450
Tetrachloroethene 127-18-4 17.5
Toluene 108-88-3 150
Trichloroethylene 79-01-6 300
Vinyl acetate 108-05-4 100
Xylene (m, o, p combined) 108-38-3 + 95-47-6 + 106-42-3, 179601-23-1 + 95-47-6, or 1330-20-7 350
Post Date: 09 Feb, 2017
Status: Approved

(Approved.)
Projects located in areas where annual average ambient PM2.5 levels are 35 µg/m³ or higher may utilize one of the following alternative strategies to satisfy Part 2.
- Replace the PM2.5 level in part 2b with 25 µg/m³. Projects using this option are limited in WELL Certification level to Gold, no matter how many optimizations are achieved.
- Replace the PM2.5 level in part 2b and the PM10 level in part 2c with a level equal to 30% of the 24- or 48-hr average of ambient outdoor levels on the day(s) of Performance Verification. Projects using this option are limited in WELL Certification level to Silver, no matter how many optimizations are achieved.
Features>Air>01. Air quality standards