1004 a - Heat Sensor June 2023
The Heat Sensor was developed to show that a Ground Ladder has been heated above 300 degrees, per NFPA 1932 requirements. If the sensor turns black in the middle, the ladder is to be taken out of service and subjected to a Horizontal Bend Test per NFPA 1932, and if it passes that test it may be put back into service so long as no other damage has been done. The sensor has an expiration date on it which is good for five years from year of purchase or after it has changed color.
The June 2023 Heat Sensor has a 4 year shelf life.