Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:10:p5
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 10 (pt 5/7)
Character Range: 1133778–1136814

the establishment of a qualitative or quantitative relationship between risks and benefits of exposure to a chemical substance, involving the complex process of determining significance of the identified hazards and estimated risks to the system concerned or affected by exposure. Risk evaluation is an element of risk management. Risk evaluation is synonymous with risk-benefit evaluation.
Risk management is a decision-making process involving consideration of political, social, economic, and technical factors with relevant risk assessment information relating to a hazard to determine an appropriate course of action.
Safety involves the practical certainty that adverse effects will not result from exposure to a chemical substance under defined circumstances. It is the reciprocal of risk.
Screening criteria are concentration values used in screening. Usually published for the purpose by an authoritative body (for example, HILs) or derived according to a specified methodology.
Screening is the process of comparison of site data to screening criteria to obtain a rapid assessment of contaminants of potential concern.
Sensitive groups are sub-populations with both susceptibility and vulnerability factors.
Sensitivity analysis is the process of changing one variable while leaving the others constant and determining the effect on the output. The procedure involves fixing each uncertain quantity, one at a time, at its credible lower bound and then its upper bound (holding all other at their medians), and then computing the outcomes for each combination of values. It can be used to test the effects of both uncertainty and variability in input values.
Site means the parcel of land being assessed for contamination.
Site-specific target levels are risk-based concentration values derived using Tier 2 or Tier 3 exposure modelling. May be used as criteria for further assessment or as clean-up levels.
Source is the contaminant that is considered to represent a potential risk requiring assessment.
Sub-chronic exposure is a contact between a chemical substance and a target of intermediate duration between acute and chronic. Different bodies vary on their definitions of the duration of 'sub-chronic' exposure, since it varies with species. US EPA uses up to 10% of an organism's lifetime (enHealth 2012a); however, between 3 and 6 months is often used when discussing sub-chronic exposure to people.
Susceptibility refers to intrinsic biological factors that can increase the health risk of an individual at a given exposure level. Examples of susceptibility factors include genetic factors, late-age and early-life, prior or existing disease.
Threshold is the dose or exposure concentration of a chemical substance below which a stated effect is not observed or expected to occur.
Tier 1 assessment is a risk-based analysis comparing site data with generic published screening criteria for various property uses (for example, residential, commercial and industrial). This tier has the lowest data requirement, generic