ABSTRACT
Risk characteriz ation in a screeni ng eco logical risk assessment con sists of using exposure an d
effects informat ion to screen the risks into categor ies. The most general categorizat ion is:
ments or decisio ns . Indeter minate-ri sks that are not clear ly signi fican t or insi gnificant and must be resol ved
by furth er assessment or con siderati on of other issue s such as co sts, benefi ts, engineer ing
feasibil ity, or public concerns . De manifes tis —ris ks that are clear ly signifi cant and need not be assessed further but
should be referred to the risk manager for remedi ation or control
These Latinisms are derived from legal terminology. In particular, some risks or other legal
issues are so small that they are considered trivial (de minimis) and therefore not worthy of the
law’s attention (Travis et al. 1987; Whipple 1987). Commonly, this three-part logic is reduced to
two parts by replacing de manifestis and indeterminate risks with a single category, nontrivial
risks. In that case, the nontrivial risks are carried forward to subsequent assessments.
