Clean Weed: HVAC System Cleaning Plays a Critical Role in Product Safety and Quality

Posted on 07/21/2020

After legal recreational marijuana sales started in Colorado in 2012, the industry has sprinted ahead, and now reaches from coast to coast. Currently, 11 states and Washington, D.C. have legalized recreational marijuana, and another 22 states have legalized it for medical use.

As the industry grows, so do profits and employment. According to “Marijuana Business Factbook,” the industry is expected to reach profits of a whopping $77 billion by 2022, while another study has found that the industry could have a workforce of around 330,000 by the same year.

All that growth brings with it the healthy competition any free market will experience. Cannabis cultivators vie for the clout of producing a superior product under standards designed to set the top-tier cultivators apart from those producing a lower-quality product. Those standards include stringent air quality controls both in and around cannabis grow facilities, in which air duct cleaning plays an integral role.

Critical Environmental Control

Cannabis may be grown outdoors or hydroponically indoors in environmentally controlled growth rooms and greenhouses. Factors such as humidity greatly affect the growth, yield, and quality of cannabis grown in indoor facilities. In addition, plant pathogens such as mold are prone to these environments, and infect marijuana plants. Mold infections reduce growth of the crop by affecting the roots, crown, and leaves, and can have serious effects on the overall yield of a crop. Beyond destroying the crop, mold can infect plants during development or after harvest, reducing product quality. One key way the spread of these pathogens is controlled in a cannabis grow facility is through effective ventilation and HVAC system cleaning.

“Certainly, you talk to any cultivator and they will tell you that the environmental controls in their grow facility are really the number one concern, particularly when you’re talking about indoor or greenhouse production,” said Ben Gelt, Board Chair of the Cannabis Certification Council. Cannabis cultivators who are serious about their product receive guidance from the Cannabis Certification Council, a nonprofit standard-holding body focused on providing consumer and industry education, transparency, and choice in the cannabis industry.

In a study called “State of the Growing Environment,” 78% of participants said that performance and efficiency were important aspects when they investigated purchasing HVAC systems. In the same study, 67% of participants expressed that “target growing humidity” was key to purchasing an HVAC system. Gelt said that during his time in the cannabis industry, HVAC contractors have become a big part of grow houses. “I can’t tell you how many different business owners and cultivators over the years tell me that their HVAC guy is their best friend, so I think it’s a core and critical part of the picture for any cultivation,” said Gelt.

According to the Resource Innovation Institute, a nonprofit that establishes industry standards and facilitates best practices to drive resource efficiency, regular maintenance of an HVAC system and lighting system could reduce grow house operating costs up to 30%.

Bill Lundquist, ASCS, CVI, founder of Monster Vac and former NADCA (The National Air Duct Cleaners Association) president, explained how keeping HVAC systems maintained and properly cleaned can prevent problems and help them to run more smoothly. “Standard maintenance and cleaning of an HVAC system is important for any building to maintain the performance level of it,” Lundquist said. “It’s even more so in grow facilities because the particulate floating in the air will clog up the HVAC systems.”

When it comes to controlling outside pathogens, each business has its own variation of control. “Every business does it differently,” said Gelt. Some facilities have an open-door policy and welcome visitors to tour the space and learn about their cultivation. Many other facilities more tightly regulate visitors and access to the growing space and have strict protocols for their employees. “In extreme cases, you have people with really significant things like doors to keep things blocked and filtered,” said Gelt.

An Inside Problem

Tight controls on visitors and movement through growing rooms is to avoid introducing pathogens into the growing space, elevating the quality and ensuring the safety of the product. However, one particularly problematic element doesn’t come from outside: resin.

“The issues I run into in grow facilities are that system performance has been compromised due to the resin that’s in the air,” said Lundquist. “It gets on the components, on the coils, restricts airflow, hurts the heat exchange, and keeps the systems from performing the way they were designed.”

The resin produced cannot be cleaned using normal duct cleaning processes, like using a vacuum or any kind of dry cleaning technique, as the duct and air handler contamination is too sticky. Lundquist also explained that from his experience, cleaning techniques will most likely change to a wet cleaning process instead of a dry cleaning one. Lundquist suggested that even though there is currently no standard for grow houses and HVAC, NADCA cleaners should stick to the current Assessment, Cleaning and Restoration (ACR) Standard when servicing grow house clients.

Bringing in a NADCA Pro

Beyond the challenges of cleaning resin, air duct cleaners working with cannabis growing facilities may encounter other types of issues plaguing HVAC systems. “You may discover a microbial problem and air quality issues having to do with fuzzy mildews and other forms of microbial contaminates,” Lundquist said. “But that’s more of a geographic thing. Some parts of the country may have more of an issue with that than other parts.”

Lundquist advises NADCA members to bring in a certified IAQ professional for microbial contamination sampling. “Let the IAQ professional take the sampling, and have them make the recommendation on what should be done if microbial contamination is present,” he said.

However, there are HVAC performance measurements that a NADCA contractor should take, including airflow, pressure drop across a coil, temperature, and humidity measurements. “These are the kind of things that are within the NADCA contractor’s skill set, and should be done,” said Lundquist. “All of these measurements are affected by the tremendous amounts of resin that floats around in the air, collects on the HVAC equipment and restricts air flow.” This restricted air flow will result in compromised system performance and, possibly, a lower-quality product for the customer.

With the cannabis industry in an upward projection for many years to come, if NADCA members aren’t looking at cannabis grow houses as a potential client, it may be time to reach out and see what you can do for them.

Article originally written by Kevin Howard for DucTales magazine.





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