TECHNICAL DETAILS ON HOW SCORES ARE DERIVED
The IRCH system assigns hazard scores between 0 and 100 based on the
Environmental Hazard = HVwater+ HVair + HVland + HVglobal
The IRCH system is an improvement over other ranking systems because it considers ecological impacts in water, air, and land. In contrast, the UTN system, for example, only considers aquatic ecosystem effects.
Several policy choices influence the rankings that result from use of
this algorithm. First, it is possible to give equal or different weights
to hazard values for the various endpoints within an effect category
(e.g., to give double weight to compounds that harm aquatic life).
Second, some method of assigning hazard values to parameters that lack
data is required (e.g., to treat the absence of data as indicating the
absence of hazard, or to penalize data gaps). IRCH uses several
alternative chemical rankings based on different versions of these
EDF was unable to extend the IRCH system to additional chemicals
because the Scorecard lacks some of data elements that are required by
IRCH: IIndiana Relative Chemical Hazard Score. Indiana Clean Manufacturing Technology and Safe Materials Institute.
Values from Indiana Relative Chemical Hazard Score - CAS Order (Updated 5/22/02)