Production of Polysilicon using a Modified Siemens Process

Pre-condition: Process not running
Flow of Events:
1. Maintenance operator inspects reactor
2. Detects leak, most likely through a pressure test
3. Operator determines if leak can be fix through patching or replacement
is immediately necessary
4. Reactor is either fixed or replaced according to the need
5. Maintenance is documented
Post-condition: Leak is fixed, and process is able to continue without
increased operation hazard levels
Scenario (3.2): Sensor and Piping Maintenance
Description: Sensors and pipes will be inspected for performance
Primary Object: Sensors
Primary Actors: Maintenance Operator
Pre-condition: Process is not running
Flow of Events:
1. Operator inspects the sensor for any signs of problems as well as proper
settings
2. Operator inspects the pipes for build-up or clogs or weaknesses
3. If there is a problem, the operator will take appropriate action, whether it is
replacing the sensor/pipes or fixing the settings
4. The operator documents the actions taken and the date the inspection took
place
Post-condition: Sensor and pipes are ready for optimal performance.
Scenario (3.1.2): Temperature Sensor Maintenance
Description: Temperature Sensor tested for accuracy and performance
Primary Object: Temperature Sensor
Primary Actors: Maintenance Operator
Pre-condition: Process not running