Sprinklers must be installed opposite obstructions.

• A. On the same side
• B. Directly under obstruction
• C. Adjacent to obstruction
• D. On the opposite side

Answer: (D)

Placing sprinklers so they’re opposite obstructions is about ensuring the water spray can reach the protected area without being blocked. When a sprinkler is on the opposite side of an obstruction, the discharge has a clearer path across the space, reducing shadowing from the obstruction and preserving the intended coverage.

If the sprinkler were on the same side as the obstruction or directly under it, the obstacle would be more likely to interfere with the spray pattern, limiting effectiveness. Being adjacent to the obstruction also risks partial blockage or distorted patterns. The opposite-side placement avoids these issues by giving the spray a direct, unhindered route to the area that needs protection.

So, the best placement is opposite the obstruction because it maintains the designed coverage and reduces the chance of the obstruction shadowing the sprinkler’s discharge.