PRELIMINARY SOURCE EVALUATION. The process (and resulting documentation) of evaluating releases or threatened releases of hazardous substances, pollutants or contaminants from source areas with the potential to constitute a threat to public health, welfare or the environment. A PSE does not constitute a preliminary assessment or site inspection. A PSE may consist of two phases: an existing data evaluation (PSE-1) or a limited field investigation (PSE-2).
Planned Special Exposures (Reg Guide 8.35). Restricted to special circumstances where the dose to the individual cannot otherwise be avoided, and, which causes the annual limit for that individual to be exceeded. The PSE provides for an additional dose, equal to the annual limit, to be used by the individual, after a thorough evaluation is conducted which justifies the additional dose is absolutely necessary to complete the job requirements, and, where no other individual is available.