Tier Screening Value Basis Action
I > 1.5 ug/m^ NAAQS (intended to keep Aggressive cleaning - if
99.5 % of childhood levels persist, take additional
population below 30 ug/dl action to reduce exposure
II .1 ug/m^ - 1.5 ug/m3 .1 ug/m3 - UBK Lead Model Maintain recommended
default value for urban (diligent wet/HEPA) cleaning
background methods -consider additional
monitoring
III .1 ug/m^ (orbackground) Determination of local No further action
background
♦PAHs (settled dust)
NYC-WTC_000151133
OCR can misread numbers and units. Confirm readings against the page image before using them.
NYC-WTC_000151133Source: NYC Law Department, mirrored locally