A protective strainer is required on the upstream side of the first check valve unless it is what type of system?

A protective strainer is required on the upstream side of the first check valve unless it is what type of system?

• A. Residential System
• B. Commercial System
• C. Water Heater System
• D. Fire Safety System

Answer: (D)

The main idea is to keep water flow cleanly protected without adding anything that could impede a critical water supply. A protective strainer upstream of the first check valve guards against debris that could cause the valve or backflow preventer to jam or fail. That works well for typical residential or commercial systems, where a little pressure loss from the strainer isn’t critical and cleanliness of the supply can vary. But for fire safety systems, reliability and maximum flow are essential. A strainer on the upstream side of the first check valve would create a pressure drop and could become clogged, potentially delaying or reducing the water available to firefighting equipment when it’s most needed. Because of that need for unobstructed, high-volume flow, the requirement for the protective strainer does not apply to fire safety systems.

The main idea is to keep water flow cleanly protected without adding anything that could impede a critical water supply. A protective strainer upstream of the first check valve guards against debris that could cause the valve or backflow preventer to jam or fail. That works well for typical residential or commercial systems, where a little pressure loss from the strainer isn’t critical and cleanliness of the supply can vary.

But for fire safety systems, reliability and maximum flow are essential. A strainer on the upstream side of the first check valve would create a pressure drop and could become clogged, potentially delaying or reducing the water available to firefighting equipment when it’s most needed. Because of that need for unobstructed, high-volume flow, the requirement for the protective strainer does not apply to fire safety systems.