Industrial Boiler MACT Rule

Reading the article on the Industrial Boiler MACT Rule (“Understanding the Industrial Boiler MACT Rule,” June 2010, leads me to this question: Do we need to be addressing our boilers for compliance? I work for a rural hospital with three locations. We have a variety of boilers dating from 1957 to our newest, installed last year with NOx- (nitrogen-oxide-) measurement devices. Can you give me any guidance?
David Schairbaum
Community Hospitals and Wellness Centers
Bryan, Ohio

Author's response:

The first criterion for Boiler MACT applicability is that your boilers must be located at a facility that is a major source of hazardous air pollutants (HAP). A major source of HAP is any facility with the potential to emit (PTE) more than 10 tons of a single HAP or more than 25 total tons of HAP in a single year. If your facility is not a major source, then your boilers are not subject to the rule. Typically, a major-source facility is one that contains coal-fired boilers, oil-fired boilers, and/or manufacturing processes with air emissions in an amount that trip the HAP PTE thresholds.

I assume your hospital has only relatively small natural-gas-fired boilers and no other air emissions. Therefore, I do not believe your facility is a major source of HAP. Also, in the U.S. Environmental Protection Agency's database of approximately 1,500 Boiler MACT-affected facilities, there is only one hospital.
Don Wolf, PE
Burns & McDonnell
Chesterfield, Mo.

Sustainable Shaft Grounding

Thank you for publishing the article “Extending Motor Life With Sustainable Shaft Grounding” (by Adam Willwerth, May 2010, It was very informative and to the point. It summarized very briefly all of the factors contributing to motor-bearing failure. I have some experience with large-motor-bearing failure and variable-frequency drives. My research found conflict causes and several solutions. After reading this article, I feel confident that my solution was the correct solution.
Anthony J. Zabloudil
Luckett & Farley
Louisville, Ky.

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