If sprinklers have been installed, what effect does it have on flame spread rating?

If sprinklers have been installed, what effect does it have on flame spread rating?

• A. Reduces flame spread rating by one classification
• B. Increases flame spread rating by one classification
• C. No effect on flame spread rating
• D. Reduces flame spread rating by two classifications

Answer: (A)

Sprinklers slow flame spread by cooling the surface and limiting heat release, and codes recognize this protection by allowing the flame-spread rating to be treated as one class better when sprinklers are present. So a material that would be rated at a given class can be considered one class more fire-resistant in a sprinklered space. It’s not a two-class shift, and there’s still a rating concept tied to surface tests, not an absolute change in material performance alone.

Sprinklers slow flame spread by cooling the surface and limiting heat release, and codes recognize this protection by allowing the flame-spread rating to be treated as one class better when sprinklers are present. So a material that would be rated at a given class can be considered one class more fire-resistant in a sprinklered space. It’s not a two-class shift, and there’s still a rating concept tied to surface tests, not an absolute change in material performance alone.