New standard establishes a common platform that allows increased cost-effective retrofit flexibility. The Underwriters Laboratories’ new edition of the fire alarm controls standard may prove to be one of the most significant changes the fire- and life-safety industry has seen in the past 20 years. “The 9th edition of UL864 is bordering more on revolutionary [...]
New standards cut back system failure risks. In May 2004, Underwriters Laboratories (UL) revised UL 1971, regulating how operating currents are to be measured and how voltage ranges are to be listed and published. Historically, fire-alarm system designers used 24-volt current draw for computing voltage drops on audible and visible (AV) circuits. However, voltage drops [...]