Critical facility HVAC and indoor air management is not all alike! In doing my homework for writing this column on critical facilities, I have been struck by the precision of IAQ monitoring in data centers.

On average, Americans keep their smartphones for two years before trading up to the latest model.

This month, I am continuing my recent exploration of situations where building systems do not pass their commissioning functional performance tests at the end of construction.

There was a time when energy efficiency was not a criterion for designing critical environments.

The ability of engine-powered generators to start and supply standby power of acceptable frequency and voltage within 10 seconds of a utility outage has made these generators the standby power system of choice for a wide variety of facilities including mission critical.

To this day, the greatest surprise of my life occurred when I was a young student at Berkeley Junior High. At the year-end assembly, unexpectedly, I heard my name called as they announced the recipient of the Seventh Grade Citizenship Award.

Over time, many if not all employees eventually become comfortable in their work environment. I don’t think this can be helped, be-cause with routine comes contentment.

Reactors for AC drives are available as either AC reactors or DC reactors (DC link chokes). Both serve the same main purpose: to smooth the current flow to the AC drive, and reduce damaging harmonics produced on the power line.

125 South Wacker, a 31-story Chicago high-rise that is halfway through a five-year master plan, represents a massive undertaking both in volume and scope of equip-ment.

Last month’s column (February 2015) addressed the potential situation where the design engineers specify a change to a system which has already passed its commissioning functional performance test.