What is the color of the glass bulb in a 155°F (66°C) temperature-rated sprinkler head?

What is the color of the glass bulb in a 155°F (66°C) temperature-rated sprinkler head?
A . Orange or red
B . Yellow or green
C . Blue
D . Purple

View Answer

Answer: A

Explanation:

The color of the glass bulb in sprinkler heads indicates the temperature rating at which the bulb will activate. These colors are standardized under NFPA 13:

155°F (66°C) temperature-rated sprinklers are classified as Ordinary temperature range, and the glass bulb is typically orange or red.

The colors correspond to the following:

Orange/Red: 135°FC155°F (57°CC68°C)

Yellow/Green: 175°FC225°F (79°CC107°C)

Blue: 250°FC300°F (121°CC149°C)

Purple: 325°FC375°F (163°CC191°C)

Reference: NFPA 13, Table 7.2.2.1: Sprinkler temperature ratings and corresponding bulb colors.