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How the Global Influenza of 1918 Impacted the Heating and Ventilation Industry

Updated: May 7, 2020




Dan Holohan a known authority on steam systems, and legend to many in the building industry. This self-taught expert has been able to continually captivate new audiences for years that followed his initial start in 1970. His original masterpiece, The Lost Art of Steam Heating started the domino effect for many books that followed. (Click here for our first interview) You can see more of Dan's work at heatinghelp.com


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On March 13th, 2020 I called Dan. I remembered from his book, how the heating and ventilation industry changed after the flu pandemic of 1918. The moment I saw things moving in a similar direction, I really wanted to learn how the economy recovered after dealing with the two-year global tragedy. Initially I hesitated to share our conversation. There was so much panic going on. I didn't want to add to it. About a week after our call, a lot of what he said was going to happen, did! New York City was put on pause when nonessential businesses were mandated to close. More testing started happening and a number of cases in the United States soared. Although there is still much uncertainty and it may be too soon to start anticipating all that will happen, I do believe it's necessary to start preparing for the changes we may see or at least start thinking about it. After Dan introduced himself, he shared some details about his book and how he stumbled across the fresh air movement in his research. Listen to what he said:

Dan: Hi everybody. I'm Dan Holohan. I'm a writer. I've written twenty-six books and probably 1,000 magazine columns for plumbing and mechanical supply house times, contractors; I mean, so many of the heating industry magazines over the years. I've been at it for probably 35 years. I retired from public speaking in 2016 but I continue to write, I wrote a lot about steam heating and then doing that and out of the research for a book I wrote years ago, The Lost Art of Steam Heating. I was reading a lot of these old engineering books that go back to the, you know, the 1800s. And when I got to the books that were written in the 1920s, they began to refer to the 'Fresh Air Movement.' This is like in an engineering text. It would say due to the Fresh Air Movement, we must now size our systems to have boilers and radiators that can heat on the coldest day of the year with the windows open.

And I had no idea what that was about. So that led me away from the technical stuff into the social stuff. And that was when I first came across the Spanish Influenza, which was not taught to me in school. And it turns out that it's the worst disaster in human history, the Spanish influenza, because it affected fully one third of the entire world's population and killed 50 million people in one year. When we came out of that in 1919 there was so much horrible memory from all the people that had died. I mean in my family alone, my father was born in 1920, but he lost three of his brothers to the Spanish influenza that one winter. Every family went through something like this. This as a result led strangely directly to the roaring twenties because we had a world where the flu came and went and didn't repeat itself fortunately.

And people looked at each other and they said, you know, well look at this. What are we going to do now? And they decided to have a party and they partied for ten years. When they stopped partying, the stock market crashed due to the partying, and we went into the great depression. The heating industry was facing this problem of the systems were installed during the 1920s were so grossly oversized to deal with the open window ventilation because the board of health was demanding the people keep their windows open and allow fresh air in, because of the Spanish Influenza was passed through the air by people coughing and breathing. We suddenly had all these oversized radiators and oversized systems and they didn't know what to do. So the appeal to the government, and in the early 1930s the National Bureau of Standards to research found that if they used a special kind of paint called bronzing, but specifically aluminum, bronzing paint, the metallic flakes in that paint would cause the radiant ability of the radiator to change by 20%. By painting the radiator, that distinctive silver color, with that special paint, you could cut down its ability to radiate by 20%. And then they found out that if you use the radiated cover that has holes in the front, but a solid top, you could further reduce the radiator size by 30%. By painting the radiators silver, and by putting the covers on them, they effectively downsized the radiator by that much, which is why the radiators are the color that they are, that you see.

And that's why the radiators have the covers on them. It's not to keep the kids from being burned, it's to deal with the oversized radiator. This social event, the Spanish Influenza had this dramatic effect on the way the industry worked. And we're still dealing with that to this date, because many of those buildings still stand and we're still trying to figure out what do we do with these oversize boilers and all the size radiators? The problem in our industry, however is that when people replace boilers, rather than going around and figuring out how to size the new boiler by measuring radiators in the case of steam or by doing heat loss calculations, in the case of hot water heating systems, they just use whatever the old boiler is and they replace like for life. We continue to put oversized boilers into buildings, which is crazy. So that's how I got involved in this and this. This particular strain of virus is very similar to the Spanish Influenza.

Annmarie: Obviously the heating industry has changed a lot and I've seen the advancements in a lot of the buildings that we have done or are putting up in a lot of the hospitals. I can't even tell you the technology that's going in. So on how we've addressed certain things pertaining to the old type, residential with the silver paint and the radiant covers has changed also. I can see how this situation is really going to change. Probably reinvent a new way of design also.

(Interlude) During our discussion, I was initially under the impression that it was only in 1920 that concerns were raised about ventilation, but Dan explained that changes in ventilation happened earlier. Unfortunately, not all of the studies were reliable at that time. Listen to what happened after the Civil War.

Dan: It went back even further than that, there was a first movement toward the fresh air after the Civil War when two people, one was Lewis Leeds who was in charge of army medical stuff during the civil war and then became the head of the Franklin Institute afterwards. He was a very influential scientist and he got together with Harriet Beecher Stowe who had written Uncle Tom's Cabin and the two of them went on a national tour where they talked about the national poison, which they referred to as vitiated air. This is all before we discovered that there were germs. It's before Pasteur and, and all of that advancement. But they believe that the disease was caused by people being in close confines and breathing. They felt that when you breathe air out, these toxins are coming out of your body and sink down to the floor and if you get near these, then you're going to get this and die.

And they went out with this lantern show where they were showing, early versions of slide projectors and, I had some of these slides for a while, and they show a man sitting in his rocking chair and his wife was sitting next to him and little baby crawls into the room and the baby's got a bonnet and the long dress and you see the guy breathing and this red stuff is coming out of his mouth and like the asthmatic goes across the floor and the baby crawls into it and then tumbles over. You can imagine the impact on parents when they went around and they showed this at school meetings all over America. And especially coming from these two Harriet Beecher Stowe and Lewis Leeds who knew more about this than them, although they were completely wrong, but they're speaking at a time when the city's attaining with immigrants and everybody's living in very close quarters.

And we went through this time when heating was brand new, starting in like 1865 and people were deathly afraid of being in closed rooms. And that led to the development of better tenements and new laws where you have more windows. What happened after 1919 with the Spanish Influenza had happened once before after the Civil War. It's not the first time we've been through this where people panic over being in close spaces with each other where there's not enough ventilation. Watch what happens in the heating industry with ventilation as we move forward out of this. Can see all kinds of advancements, I think.

Annmarie: I completely agree with you Dan. It is the primary reason for me having you on this call.

(Interlude) Some of the other items we discussed is now known by most, but Dan had raised some interesting points that I surely wasn't thinking about. Some men may have a new look after listening to this.

Dan: Once these test kits get out there, which would probably be between the next two weeks that they should be really testing here. These numbers are going to soar because people have this, but it's not showing and everything we're seeing now with the closings of sports and gathering places and the run on things in stores, it's going to get dramatically worse within the next couple of weeks. So, life as we know it is about to change and eventually this thing will wear itself once enough people get infected. I don't believe it's going to change when the weather gets warm because right now, and in Singapore where it's hot all the time, it's growing. The virus is growing. And in Australia where it's summertime, the virus, it doesn't seem to be reacting to temperature of the air outside. It just seems to be something that's going and really the only way around it, is as they say, wash your hands, don't touch your face and stay away from people.

Annmarie: All we could do is really kind of unfortunately wait it out.

Dan: Yeah. And it'll take a year for the vaccine to appear and in the meantime, it's going to do a lot of damage, I believe. But it's nothing that we have lived through yet, but it has been lived by previous generations. You know, the Spanish Influenza being the greatest example. I don't think it's going to be that bad, as bad, from what I'm reading and seeing, but I do believe it's going to be enough to get everybody's attention.

Annmarie: Yeah. And I think, like you said, once the numbers get out. The fact that there were a lot of people who couldn't afford to go and actually get the tested, just not even talking about the, the testing, first of all, not being available to some. Just because of the demand of it. Right? Supply and demand.

Dan: Exactly. Exactly. That's the thing. We've got less than a million hospital beds in America and 70% of those are filled with people that have other things going on. Heart disease and things like that. So. And I heard there were 65,000 ventilators in the whole country.

We simply don't have the infrastructure. You know, all they can do at this point is to try to flatten the curve where you're, rather than having this thing suddenly appear where everybody's got it, to by closing venues where people get together, it'll spread it out so that it'll go over a longer time. But there'll be fewer people that need immediate care right now, right today. That's the challenge right now. So that's why they're putting so much emphasis, particularly the governors now, closing schools for the entire state and you know, closing sports and things like that. Because the more we get together, the more we're going to pass this on.

My wife was saying, what about the mailman? The mailman, if you have one mailman, because this stuff lives on paper and cardboard and if one man has got this virus and he's, and he's delivering the mail, he's still delivering it to everybody's house. And that's, you know, we don't think about these things. If you go into a store and you're washing your hands, as soon as you grabbed the handle to open up stores the door, you could be having this stuff on your hand and you may not touch your face, but you may touch something else. So that's why it's, that's why it's happening so quickly and, and this is why they're encouraging people to just stay put. I think about guys that have beards and mustaches are constantly touching that thing. You know, just put your hands down.

Annmarie: Oh man, I didn't even think about that too. Yes!

Dan: They can't talk to you unless they are stroking their beard. Put your hands in your lap.

Annmarie: I wonder if that'll change even from a social perspective where the guys will actually start shaving off their beards now?

Dan: Well, we can only hope.

Annmarie: Take it from a man who has no beard.

Dan: Yeah. Not now.

Annmarie: It's always fun talking to you Dan. It really is, and I love to get your world of information because I feel like you have so much and I see it as an opportunity of capturing it and memorializing it, any and every way that I can.

Dan: Well, thank you. Appreciate that.

Annmarie: You're welcome. Is there anything else that you wanted to add?

Dan: No, I just wanted to thank your tribe for listening in and you're doing a great job and it's all about the listeners, so thanks folks.

Annmarie: Yeah, thank you so much, Dan. I really appreciate it.

Dan: Oh, you're welcome. My privilege. Thanks.

I hope this episode has provided a different perspective. I know if new codes are mandated, there will be a ripple effect in the industry and new opportunities will emerge. Building codes affect HVAC design, the equipment that has to be installed, the energy efficiency we will see, and all in guidance of how local laws will be mandated. I encourage everyone to learn from history and start thinking about ways we will positively impact the future of the HVAC industry. As history has shown us, rash decisions can create costly repercussions for many years to come.


The next couple of months will be tough on many, but as stressful as it may seem, I encourage you to choose at least one of the many online options that we have today that most didn't have in 1918. Take the time to learn a new skill with an online course, participate in webinars, join a LinkedIn group, think about a side hustle. Whatever it is you choose, decide on completing it. EBS is working on sharing more online content. If you're listening to this, you have connected to us on one of our many platforms. We encourage you to keep listening and keep learning. We are sending prayers to all who are currently fighting this virus and praying that everyone stays safe and healthy. Until the next episode. See you then.


Enhanced Building Solutions LLC (EBS) offers training and consulting. Our training methods provide consistent information, saves on employee turnover, and minimizes liabilities. Nothing will ever replace hands-on learning but blending it with online resources will create an IDEAL training solution. Are you ready to be a pioneer in the industry?


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