Under what condition may the line-to-line distance be 12 ft 6 in?

Under what condition may the line-to-line distance be 12 ft 6 in?

• A. Structural members are 25 ft apart and density > 0.25
• B. Density > 0.25 regardless of structure
• C. Structural members are 20 ft apart and density > 0.25
• D. Structural members are 25 ft apart and density <= 0.25

Answer: (D)

In foam-water sprinkler system design, how far apart lines can be spaced is controlled by two factors: how far apart the structural members are and the density of the foam solution. When structural members are spaced widely (25 ft) and the foam density is kept at or below 0.25, you can use a line-to-line distance of 12 ft 6 in. The lower density means the foam solution can still provide adequate coverage even with wider spacing, while the 25 ft structural spacing supports the distribution layout without creating gaps. If either condition isn’t met, the line-to-line distance must be reduced. A closer structural spacing (like 20 ft) or a higher density (greater than 0.25) would require tighter line spacing to ensure proper coverage and avoid uncovered areas.

In foam-water sprinkler system design, how far apart lines can be spaced is controlled by two factors: how far apart the structural members are and the density of the foam solution. When structural members are spaced widely (25 ft) and the foam density is kept at or below 0.25, you can use a line-to-line distance of 12 ft 6 in. The lower density means the foam solution can still provide adequate coverage even with wider spacing, while the 25 ft structural spacing supports the distribution layout without creating gaps.

If either condition isn’t met, the line-to-line distance must be reduced. A closer structural spacing (like 20 ft) or a higher density (greater than 0.25) would require tighter line spacing to ensure proper coverage and avoid uncovered areas.