Question

18 multiple choice 1 point process technicians are responsible for performing which of the following tasks involving raw water supply systems? clean and inspect screens. sample water and add chemicals as needed. control disinfection and inspect water for foaming. operate fans and monitor clarifiers. 19 multiple choice 1 point which of the following tasks may expose process technicians to the hazard of moving parts? working in cold weather injecting chlorine cleaning screens cooling towers

Explanation:

For question 18: Process technicians in raw water supply systems are tasked with routine sampling of water to test quality and adding treatment chemicals as required based on those samples; other tasks are either more specialized or not core to raw water system technician duties.
For question 19: Cleaning screens in water systems often involves interacting with equipment that has moving components (like screen mechanisms), which poses a risk of exposure to moving parts, unlike the other listed tasks which carry different hazards.

Answer:

1. Sample water and add chemicals as needed.
2. Cleaning screens