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To download the most recent Regional Screening Level tables, please go to the Generic Tables page. For assistance/questions please use the RSL Contact Us page.
The What's New section keeps users informed of changes to: toxicity values, exposure parameters, chemical-specific parameters, equation formats and any other SL changes. Please check this site frequently to be advised of any recent changes.
The tables released on May 18, 2020 mistakenly applied the oral slope factor for nickel refinery dust to nickel soluble salts. This mistake has been corrected. All affected tables have been replaced with corrected tables. This includes the tables presented on the Generic Tables page and also the changes and comparison tables linked below in the May 18, 2020 update section. Corrected tables have (corrected) in the header. The residential and commercial air tables, chemical parameter tables, and subchronic tables were not affected.
RISK=(RSL_TR x User_C)/RSL_C or HQ=(RSL_THQ x User_C)/RSL_C
Whether this calculation will suit the needs of a given project depends upon site-specific decisions, the conceptual site model, the purpose of the risk assessment and the authority under which it is being conducted, etc. Please consult your regional risk assessor for further guidance in site-specific situations.
All tables are presented with target cancer risk (TR) of 1E-06, however, tables are presented with target hazard quotients (THQ) of 1.0 and 0.1. Use the tables appropriate for your region.
In the November 2012 Update, the third to the last bullet that identifies the updates to the recreator landuse scenario, the following additional information may be useful.
For assistance/questions please use the Regional Screening Levels (RSLs) contact us page. For general risk assessment questions, separate from the RSLs, please use the link below.