Answer :
Final answer:
A backwater valve (optin A) is the correct equipment to protect sumps and ejectors against backflow and backpressure from the building sewer or building drain, ensuring that water flows in one intended direction and preventing potential flooding or sanitation hazards.
Explanation:
The correct option for protecting against these issues is A) a backwater valve. This type of valve is specifically designed to allow water or sewage to flow in one direction only, preventing any potential backflow into the building. It operates automatically, closing off when backward pressure from an overflowing sewer threatens to push wastewater in the reverse direction.
Backwater valves are crucial in areas prone to heavy rainfall or in buildings situated below the sewer line, where gravitational flow into the sewer might be impeded. This protection ensures that wastewater exits without the risk of flooding interior spaces or causing sanitation hazards. Options such as a pressure relief valve, a check valve, and an air gap serve different specific functions in plumbing systems, and do not provide the same level of protection against backflow as a backwater valve.
