An official website of the United States government.

We've made some changes to EPA.gov. If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Lead Air Pollution

Table of Historical Lead (Pb) National Ambient Air Quality Standards (NAAQS)

History of the NAAQS for Pb
Final Rule/Decision Primary/Secondary Indicator1 Averaging Time Level2 Form
1978

43 FR 46246
Oct 5, 1978
Primary and Secondary Pb-TSP Calendar Quarter 1.5 µg/m3 Not to be exceeded
1991 Agency released multimedia "Strategy for Reducing Lead Exposures"
2008

73 FR 66964
Nov 12, 2008
Primary and Secondary Pb-TSP 3-month period 0.15 µg/m3 Not to be exceeded
2016

81 FR 71906
Oct 18, 2016
Primary and secondary standards retained, without revision.

1. Pb-TSP = Lead in total suspended particles

2. Units of measure are micrograms per cubic meter of air (µg/m3).