Answer:
Class A
-UL 1449
Step-by-step explanation:
In simple words, Class A chemical compounds have a fire spreading ranking between null and 25. Such products are safe toward extreme exposure to flames. Class B flame resistant get a flame range ranking about 26 and 75. Fully Differential products have a fire distribution level of more than 500.
UL 1449 relates to the Safety Standard besides Survey resistant Devices (SPD) for bureau . Surge is a sudden rise in currents and voltages which can happen along AC or DC electrical loads and can affect the equipment connected to such circuits.