HVAC Surges with H1N1 Flu
May 18, 2009
Recent coverage of the latest emerging flu strain (the so-called swine flu, H1N1), has people and institutions scrambling for contingency plans, and providing people with information on everything from the right type of respirator to wear, to how to wash their hands. Part of the panic has been established by older reports warning that we have been overdue for infection on a global scale.
In the IAQ sector, manufacturers such as Sanuvox, Steril-Aire, and American Ultraviolet are being inundated with calls for information to help people and facilities owners mitigate the risks of possible infections.
According to Aaron Engel, vice president of marketing and communications for Sanuvox, customers aren’t asking whether the products will work; they’re asking what they need and when they can get it. “This is my system, what size do I need,” is what he said he’s hearing, mainly from commercial customers. “A lot of them calling up already have this installed.” They have also seen a number of calls from hospital facility managers, some of whom want UV-HEPA systems shipped for next-day delivery.
The experiences have been similar at Steril-Aire, said Robert Scheir, Ph.D., whose customers have been asking, “How fast can we get the product out the door.” While the initial panic is starting to subside, there also is an awareness that “these kinds of pandemics move in waves. The initial wave is like the shoreline, and the seventh wave is like the big one.
“Vigilance, I believe, should be continued,” he said. “What I’m hearing from the CDC is just that.” Let’s be cautious and prepared.”
“We have had about 25 to 45 calls about the virus,” said Meredith Stines, president and CEO of American Ultraviolet. “Since it is a virus, it is easily controlled by UVC.”
Steril-Aire has been seeing most of its interest from schools and commercial facilities. “Schools seem to be concerned and aggressive, and so are some of the more proactive commercial buildings,” Scheir said. “For some reason, health care seems to drag its heels. They’re always waiting for the peer-reviewed literature, so they’re not too proactive.”
“The best use is in a commercial application,” said Stine. “Our Corner Mount and TB series fixtures work best for these applications.”
WHAT H1N1 ISThis particular strain of influenza, H1N1, is being called swine flu, but it’s actually a combination of swine flu, avian flu, and common flu.
“We have a lot of information here regarding H1N1,” Engel said. “We have tackled the subject before when we were dealing with avian flu, another variation of type A influenza.” According to many sources, in its current form H1N1 isn’t particularly robust. However, viruses have a way of mutating and getting stronger, and this could become more evident as time passes.
“Pandemic” simply describes the fact that the virus is showing up in several countries across the globe at more or less the same time. It does not describe the virus’s strength; it’s more of a geographic indicator. H1N1, in fact, currently does not seem to be particularly hard to kill.
“UV is extremely effective at destroying the airborne influenza virus,” Engel said. “Our systems have been tested against viruses and spores much harder to kill than swine flu.” The Environmental Protection Agency (EPA) verified a 93 percent destruction rate of the anthrax spore on a single pass with no recirculation, he said. The anthrax spore requires 50,000 microwatts of UV energy to be destroyed.
“Influenza requires less than 5,000 microwatts for destruction,” he said. “It is safe to say that when sized properly, UV systems will be extremely effective” against H1N1, although he readily states that the EPA has not yet approved any equipment specific to this particular virus.
HOW IT SPREADSH1N1 has been shown to spread like common flu, via small airborne droplets (like those generated by a sneeze). Therefore, people need to take the usual precautions by washing their hands frequently, etc. However, it is entirely possible for the HVAC system to become a mode of virus transmission, said Scheir.
“There’s been an awful lot of talk about hand washing,” he said. “There have been rather elegant studies showing that small droplets from a sneeze or a cough evaporate very quickly, and the contaminants can spread through the air-handling system.” This shows the direct role HVAC systems can have on either spreading or mitigating an infectious disease.
“Should someone come into direct contact, or should someone physically transmit the virus (i.e., sneezing, putting your hands in your mouth, or touching your eyes), this we cannot help,” said Engel. “But should someone sneeze and/or the virus and the saliva atomizes in the air, now it is airborne.”
UV TREATMENTIt’s certainly better to be on the side of prevention instead of being pinpointed as a possible source of contamination. When applying UV equipment as a preventive or remediation method, there are different views regarding where to place the lights. “UV is very effective, but it has to be delivered a certain way,” Engel said. “If it’s an airborne influenza, it’s not very effective” if lights are directed perpendicular to the evaporator coil, the way they might be for coil biofilm treatment.
“UV systems for air treatment have a fraction of a second to deliver their energy,” he said. When used for biofilm treatment, they can shine on the coils for extended periods of time. The company’s Bio-Wall system has air passing in parallel over the lamp, providing a higher dosage of UV to treat the faster-moving air.
“The most important thing is to have properly functioning germicidal UV,” said Scheir. “There are in-room units that work well at that temperature,” such as units designed for placement high on the wall in surgical suites. “There are units designed to work well at cold moving-air conditions. And there are freestanding units that work well to clean the space. We have an in-room unit,” he said; “we have a unit that’s a sterile zone; and we do the HVAC UV.
“There’s an awful lot of junk out there,” he added, so do your homework to find the best product for your customer. “It’s caveat emptor” - buyer beware.
Scheir advises contractors to stay away from units that generate ozone. “Ozone has a half-life in the air of about 20 minutes,” he said. “If it’s mixed in the occupied space, it can be toxic.”
If contractors are going to incorporate a UVC or germicidal system into an HVAC system, “they need to know that the system that they’re putting in has sufficient energy to destroy the microorganisms flying by, and that it can maintain it until it’s time for the lamps to be changed out,” about one year, he said. “Many drop after three or four months.”
As far as Steril-Aire is concerned, “We recommend the placement of UV lamps at the coils, even for something like swine flu,” said Scheir, so that in addition to remediation, there is an energy payback. “Placing it in duct anywhere else will give you protection from the airborne, but not the biofilms.”
SELF PROTECTIONContractor Fred Kobie, president of Kobie Kooling Inc., Fort Myers, Fla., not only keeps up on best IAQ practices from a customer’s perspective, he also takes care of the health and safety of his staff. Protecting field employees from potential infection while performing their work is a high priority for him.
“We actually had our weekly training about H1N1 twice this week,” he told The NEWS. “We do have a suspected case in the Lee County school system.”
The company encourages its technicians to wear appropriate masks (N95) and gloves while working on fan coil units. “We have directed them to wash before and after the call, and we provide antibacterial soap. The eye is another access point, and we provide goggles for all technicians.” The company typically takes these precautions anyway, because of the variety of bacterial risks associated with the interiors of HVAC systems.
These types of precautions are useful at any time of year and during any normal flu season. As many people are now learning, influenza accounts for approximately 36,000 deaths per year in the United States alone.
“Residents with sick occupants should open windows and flush the air from the house as much as practical,” Kobie said. “Saturation is very effective and it’s free. Of course, wash hands and the work area, too.”
UV is “definitely doable in the residential market,” said Engel. “Our residential units are just as effective as the commercial units.”
He added that Dr. Kowalski at Penn State University “almost equates UV to an inoculation for the building. You could lessen the chance for transmission throughout the building.”
Perhaps the most important information for a contractor to learn at this time, is what the customer hopes to achieve. “What does the customer want,” asked Engel. What is it that their customers are looking for - reducing absenteeism, preventing transmission? If the customer is a medical facility, do they want to contain the contaminants? Every end user has a specific need. What is the reason for that protection?”
It’s a valid reason for contractors to press for communication with decision makers, in order to provide helpful information, devoid of hype. “It really falls into the area of proactivity on the behalf of managers and decision makers,” said Scheir.
“I think the important thing is that contractors get more and more familiarized with the technology,” he said: “how it interfaces with the biological demands of the system, the effects of contamination in the system (coil and drain pan), and how the system can be a very effective conveyor of occupied space infectious disease.”
Publication date: 05/18/2009