Mentoring Engineers

In an exchange of letters with Michael Ivanovich, editor-in-chief, I was asked to share my perspective on how to mentor younger engineers with HPAC Engineering readers. Based on more than 60 years of experience in the HVAC industry, it is safe for me to say that all of us are mentors, teachers, or both at some time. So I would say that we are at all times either teachers or learners.

My favorite story about mentoring imparts a small, but important, example. As a young mechanic, I was installing a new residential heating system. My screwdriver wasn't working properly. The homeowner noticed my problem and said, “Let me show you how to sharpen that screwdriver.” So I let him show me, and I learned two lessons: how to sharpen a screwdriver and how to accept advice.

Most of what I know I learned in similar ways, more or less incidentally. I would tell young engineers that every situation is a learning situation, and one never knows whom the teacher will be.

Out of that arises another lesson: There are no stupid questions. Most people will be happy to give you the answer without condescension. It makes them feel good, and you learn. In my early days in ASHRAE, I joined the psychrometric committee because that was one of my major interests. During a discussion on revising psychrometric tables for better accuracy, an argument developed on whether or not to use the second or third virial coefficient. After 10 minutes of this, I asked, “What is a virial coefficient?” Everyone laughed, but they explained it to me and I learned. Some time later, as a result of my experience on that committee, I was able to develop tables and charts for our use in the higher altitudes of the southwest United States.

During many years as a consulting engineer, I often had occasion to go into the field to help solve problems arising during the construction of HVAC systems. I found that the best approach was to listen to the installers. Most of the time, they had a solution. Sometimes, I knew things they did not know and could revise their solution to be more effective. But I always started with an open mind. The “do it my way” approach is not always best. Who is the mentor in these cases? Maybe all of us.

I started working as a mechanic in my father's sheet metal and heating business. Later, I was a draftsman for many years in HVAC related businesses. Finally, I went to college for an engineering degree, in part because of the fine engineers I encountered in the course of my drafting job. These men encouraged and taught me a great deal. I don't know if they thought of it as “mentoring.” Probably they were more concerned that I understood what we were doing so I could get it right. But it was mentoring all the same.
Roger Haines, retired
Laguna Woods, Calif.

Hospital Humidification

I congratulate the author for her informative and well-researched article (“Steam Humidification Systems and the Chemicals They Use,” by Shulamit Rabinovich, PE, May 2004); however, I must make one clarification. Verifying that harmful chemicals are not directly injected into the air stream should be done in all locations, not just California, as the article implies. Since 1992, ASHRAE has recommended that for direct-steam-injection humidifiers, boiler-treatment chemicals should be checked for safety and indoor air quality impact. (Refer to HVAC Systems and Equipment, ASHRAE Handbook, 2000, Page 20.8.) The Office of Statewide Health Planning and Development (OSHPD) is the agency that regulates hospital construction in California. This office issues code applications notices (CANs) periodically to interpret and/or clarify code requirements and to assist architects and engineers in the design process. CAN 4-408.1.5 simply brings the ASHRAE recommendations regarding chemicals in steam used for humidifiers to the attention of designers.

The process of analyzing and selecting the type of humidifiers that will best fit hospital needs should be done as the author describes, regardless of the location of the hospital.
Timothy Mort
OSHPD, State of California

Author responds
Thank you for your kind comments. Most of our work is in California, which is why the article refers to OSHPD CAN 4-406.2.1, which states: “If steam from the central boiler plant will be injected directly into the air stream, the design professional should verify that the boiler water will not be treated with chemicals or contain minerals which are known to be hazardous to health or which might contribute to an indoor-air-quality problem.”

This CAN recently was modified and is now superceded by CAN 4-408.1.5, which reads, “It is recommended but not required, that the design professional verify that the boiler water will not be treated.”

This revision brought CAN language closer to the cautionary, rather than mandatory, ASHRAE language: “Chemicals should be checked for safety, and care should be taken to avoid contamination from the water or steam supplies.”
Shulamit Rabinovich, PE
Ted Jacob Engineering Group
Oakland, Calif.

Letters on HPAC Engineering editorial content and industry issues are welcome. Address them to Michael G. Ivanovich, Editor-in-Chief, HPAC Engineering, 1300 E. Ninth St., Cleveland, OH 44114-1503; e-mail: