Exposure scenarios within REACH are defined as 'sets of information describing the conditions under which the risk associated with the identified use(s) of a substance can be controlled. It includes operational conditions (e.g. amounts used, frequency and duration of use etc.) and risk management measures (e.g. measures to limit/prevent release: ventilation, personal protection etc).
Library could be searched based on key parameters which will present list of related scenarios in PDF format. Each PDF provides information about a particular Worker exposure scenario.
Section 1 (General Description) provides general information on the exposure scenario and the premises. Each exposure scenario can have several Contributing Exposure Scenarios (CES). Specific information on these contributing scenarios along with Measurements data is available in the Section 2 and Section 3 of PDF reports.
Each contributing exposure scenario represents a unique situation where the operating condition changes. For example on industrial manufacture of TiO2 may include as contributing scenarios 1) synthesis in a close vessel 2) synthesis in an open vessel with local exhaust ventilation etc. If the exposure conditions are very different e.g. different synthesis methods, two exposure scenarios have to be described.
The contributing scenario can have different tasks as long as all tasks are carried out under the same operational conditions and risk management measures (e.g. amounts used, engineering controls, etc). For example a contributing scenario on feeding TiO2 into a process can have the following tasks: weighing, pouring, mixing, feeding into the process.
Each CES include measurement data (AM, GM, Min, Max, GSD, PSD data etc) if available. The measurements have been collected during a situation with the same operating conditions described or under slightly different conditions that will not affect exposure. If the operating conditions during the surveys differ in an extent that they will affect exposure they are described in different contributing scenarios. If several surveys are available for the same contributing scenario, summary statistics (AM, GM, Min, Max, GSD, etc) are entered across the different surveys and not individual survey results.