Tag Archives: air

Why the Central Chiller Isn’t So Central to Grow Room HVAC

By Geoff Brown
No Comments

There’s a better way to design HVAC for cannabis grow rooms, and it may seem a little odd at first.

Central chillers are a tried-and-true solution for projects requiring large refrigeration capacity. They’re found in college campuses, hospitals, office buildings and other big facilities.

While central chillers are a good default for most large-scale applications, they fall short in this industry. Grow rooms, with their need for tight, variable conditions and scalable, redundant infrastructure, have HVAC requirements that the central chiller model simply can’t deliver on.

Let’s unpack the shortcomings with the central chiller in this niche and explore some possible solutions.

What’s Wrong With Chillers?

Building a scalable HVAC system is essential for the cannabis industry as it continues to ramp up production in the U.S. and Canada.

Many growers are building their large facilities in phases. In Canada, this is common because growers must have two harvests before they can receive a production permit, so they build just one phase to satisfy this requirement and then build out the facility after the government’s approval.

This strategy of building out is less feasible with a central chiller.

solsticegrowop_feb
Indoor cultivator facilities use high powered lights that give off heat, requiring an efficient air cooling system.

A chiller and its supporting infrastructure are impractical to expand, which means it and the rest of the facility needs to be built to full size for day one, even though the facility will be in partial occupancy for a long time. This results in high upfront capital costs.

If the facility needs to expand later down the road, to meet market demand for example, that will be difficult because, as mentioned, it’s expensive to add capacity to a central chiller.

Additionally, the chiller creates a central point of failure for the facility. When it goes down, crops in every room are at risk of potentially devastating loss. Grow rooms are unusual because of their requirement for strict conditions and even a slight change could have big impact on the crop. Losing control due to mechanical failure could spell disaster.

One Southern Ontario cannabis grower met with some of these issues after constructing their facility, which uses a central chiller for cooling and dehumidification. The chiller was built for full size, but the results were disappointing as early as phase one of cultivation. While sensible demands in the space are being easily met, humidity levels are out of control – flowering rooms are up to 75% RH.

Humidity is one of the most important control aspects to growers. Without a handle on it, growers risk losing their entire crop either because there’s not enough and the plants dry out, or there’s too much and the plants get mold disease. This facility has fortunately not yet reported serious crop issues but is mindful of the potential impact on harvest quality.

By going unitary, capital costs scale on a linear basis.If tight control over humidity is what you need, then a chilled water system needs very careful consideration. That’s because typical chiller system designs get the coils cold enough to lower the air temperature, but not cold enough to condense water out of the air as effectively as a properly designed dehumidifier coil.

A chilled water system capable of achieving the coil temperatures needed for adequate dehumidification in a typical flower room will also require full-time reheat to ensure that air delivered to the plants isn’t shockingly cold — either stunting their growth or killing them altogether. This reheat source adds complexity, cost and inefficiency which does not serve growers well, many of whom are under pressure from both utilities and their management to minimize their energy usage.

How Do Unitary Systems Solve These Problems?

Compared to central chillers, a unitary setup is more agile.

A facility can commence with the minimum capacity it needs for start-up and then add more units in the future as required. They’re usually cheaper to install than a central system and offer several reliability and efficiency benefits as well.

The real business advantage to this approach is to open up the grower’s cash flow by spreading out their costs over time, rather than a large, immediate cost to construct the entire facility and chiller for day one. By going unitary, capital costs scale on a linear basis.

Talltrees
One of the flowering rooms in an indoor set up (Image: Tall Trees LED Company)

Growers can have more control over their crop by installing multiple units to provide varying conditions, room-by-room, instead of a single system that can only provide one condition.

For example, flowering rooms that each have different strains of crop may require different conditions – so they can be served by their own unit to provide variability. Or, rooms that need uniform conditions could just be served by one common unit. The flexibility that growers can enjoy with this approach is nearly unlimited.

Some growers have opted for multiple units installed for the same room, which maximizes redundancy in case one unit fails.

A cannabis facility in the Montreal area went this direction when building their HVAC system. Rather than build everything in one shot, this facility selected a unitary design that had flowering rooms served independently by a series of units, while vegetation rooms shared one. The units were sized to provide more capacity than currently required in each room, which allows the grower to add more plants and lighting in the future if they choose.

This facility expects to build more grow rooms in a future phase, so it was important to have an intelligent system that could accommodate that by being easy to add capacity to. This is accomplished by simply adding more units.Multiple, small systems also have a better return-on-investment.

The grower, after making a significant investment in this facility, was also averse to the risk of losing crop due to mechanical failure, which is why they were happy to go with a system of independent grow room control.

Multiple, small systems also have a better return-on-investment. Not only are they easier to maintain (parts are easier to switch out and downtime for maintenance is minimal) but they can actually be more efficient than a large, central system.

Some units include heat recovery, which recycles the heat created by the dehumidification process to efficiently reheat the unit’s cold discharge air and keep the space temperature consistent, without needing expensive supplementary heaters. There’s also economizer cooling, which can be used to reduce or even eliminate compressor usage during winter by running the unit on dry outside air only.

Demand for cannabis continues to increase and many growers are looking to expand their businesses by adding new facilities or augmenting existing ones. Faced with the limitations of the traditional chiller system, like the lack of flexibility, scalability and redundancy, they’re looking for an intelligent alternative and the unitary approach is earning their trust. It’s expected this option will soon become the leading one across North America.

HACCP

Implementing a HACCP Plan to Address Audit Concerns in the Infused Market

By Daniel Erickson
1 Comment
HACCP

The increasing appeal and public acceptance of medical and recreational cannabis has increased the focus on the possible food safety hazards of cannabis-infused products. Foodborne illnesses from edible consumption have become more commonplace, causing auditors to focus on the various stages of the supply chain to ensure that companies are identifying and mitigating risks throughout their operations. Hazard Analysis and Critical Control Points (HACCP) plans developed and monitored within a cannabis ERP software solution play an essential role in reducing common hazards in a market currently lacking federal regulation.

What are cannabis-infused products?

Cannabis infusions come in a variety of forms including edibles (food and beverages), tinctures (drops applied in the mouth), sprays (applied under the tongue), powders (dissolved into liquids) and inhalers. Manufacturing of these products resembles farm-to-fork manufacturing processes common in the food and beverage industry, in which best practices for compliance with food safety regulations have been established. Anticipated regulations in the seed-to-sale marketplace and consumer expectations are driving cannabis infused product manufacturers to adopt safety initiatives to address audit concerns.

What are auditors targeting in the cannabis space?

The cannabis auditing landscape encompasses several areas of focus to ensure companies have standard operating procedures (SOP’s) in place. These areas include:

  • Regulatory compliance – meeting state and local jurisdictional requirements
  • Storage and product release – identifying, storing and securing products properly
  • Seed-to-sale traceability –  lot numbers and plant identifiers
  • Product development – including risk analysis and release
  • Accurate labeling –  allergen statements and potency
  • Product sampling – pathogenic indicator and heavy metal testing
  • Water and air quality –  accounting for residual solvents, yeasts and mold
  • Pest control – pesticides and contamination

In addition, auditors commonly access the reliability of suppliers, quality of ingredients, sanitary handling of materials, cleanliness of facilities, product testing and cross-contamination concerns in the food and beverage industry, making these also important in cannabis manufacturers’ safety plans.

How a HACCP plan can help

HACCPWhether you are cultivating, harvesting, extracting or infusing cannabis into edible products, it is important to engage in proactive measures in hazard management, which include a HACCP plan developed by a company’s safety team. A HACCP plan provides effective procedures that protect consumers from hazards inherent in the production and distribution of cannabis-infused products – including biological, chemical and physical dangers. With the lack of federal regulation in the marketplace, it is recommended that companies adopt these best practices to reduce the severity and likelihood of compromised food safety.

Automating processes and documenting critical control points within an ERP solution prevents hazards before food safety is compromised. Parameters determined within the ERP system are utilized for identification of potential hazards before further contamination can occur. Applying best practices historically used by food and beverage manufacturers provides an enhanced level of food safety protocols to ensure quality, consistency and safety of consumables.

Hazards of cannabis products by life-cycle and production stage

Since the identification of hazards is the first step in HACCP plan development, it is important to identify potential issues at each stage. For cannabis-infused products, these include cultivation, harvesting, extraction and edibles production. Auditors expect detailed documentation of HACCP steps taken to mitigate hazards through the entire seed-to-sale process, taking into account transactions of cannabis co-products and finished goods at any stage.

Cultivation– In this stage, pesticides, pest contamination and heavy metals are of concern and should be adequately addressed. Listeria, E. coli, Salmonella and other bacteria can also be introduced during the grow cycle requiring that pathogenic indicator testing be conducted to ensure a bacteria-free environment.

Harvesting– Yeast and mold (aflatoxins) are possible during the drying and curing processes. Due to the fact that a minimal amount of moisture is optimal for prevention, testing for water activity is essential during harvesting.

Extraction – Residual solvents such as butane and ethanol are hazards to be addressed during extraction, as they are byproducts of the process and can be harmful. Each state has different allowable limits and effective testing is a necessity to prevent consumer exposure to dangerous chemical residues.

Edibles– Hazards in cannabis-infused manufacturing are similar to other food and beverage products and should be treated as such. A risk assessment should be completed for every ingredient (i.e. flour, eggs, etc.), with inherent hazards or allergens identified and a plan for addressing approved supplier lists, obtaining quality ingredients, sanitary handling of materials and cross-contamination.

GMPFollowing and documenting the HACCP plan through all of the stages is essential, including a sampling testing plan that represents the beginning, middle and end of each cannabis infused product. As the last and most important step before products are introduced to the market, finished goods testing is conducted to ensure goods are safe for consumption. All information is recorded efficiently within a streamlined ERP solution that provides real-time data to stakeholders across the organization.

Besides hazards that are specific to each stage in the manufacturing of cannabis-infused products, there are recurring common procedures throughout the seed-to-sale process that can be addressed using current Good Manufacturing Practices (cGMP’s).  cGMPs provide preventative measures for clean work environments, training, establishing SOPs, detecting product deviations and maintaining reliable testing. Ensuring that employees are knowledgeable of potential hazards throughout the stages is essential.Lacking, inadequate or undocumented training in these areas are red flags for auditors who subscribe to the philosophy of “if it isn’t documented, it didn’t happen.” Training, re-training (if necessary) and documented information contained within cannabis ERP ensures that companies are audit-ready. 

Labeling

The importance of proper labeling in the cannabis space cannot be understated as it is a key issue related to product inconsistency in the marketplace. Similar to the food and beverage industry, accurate package labeling, including ingredient and allergen statements, should reflect the product’s contents. Adequate labeling to identify cannabis products and detailed dosing information is essential as unintentional ingestion is a reportable foodborne illness. Integrating an ERP solution with quality control checks and following best practices ensures product labeling remains compliant and transparent in the marketplace.

Due to the inherent hazards of cannabis-infused products, it’s necessary for savvy cannabis companies to employ the proper tools to keep their products and consumers safe. Utilizing an ERP solution that effectively manages HACCP plans meets auditing requirements and helps to keep cannabis operations one step ahead of the competition.

Total Yeast & Mold Count: What Cultivators & Business Owners Need to Know

By Parastoo Yaghmaee, PhD
2 Comments

Editor’s note: This article should serve as a foundation of knowledge for yeast and mold in cannabis. Beginning in January 2018, we will publish a series of articles focused entirely on yeast and mold, discussing topics such as TYMC testing, preventing yeast and mold in cultivation and treatment methods to reduce yeast and mold.


Cannabis stakeholders, including cultivators, extractors, brokers, distributors and consumers, have been active in the shadows for decades. With the legalization of recreational adult use in several states, and more on the way, safety of the distributed product is one of the main concerns for regulators and the public. Currently, Colorado1, Nevada and Canada2 require total yeast and mold count (TYMC) compliance testing to evaluate whether or not cannabis is safe for human consumption. As the cannabis industry matures, it is likely that TYMC or other stringent testing for yeast and mold will be adopted in the increasingly regulated medical and recreational markets.

The goal of this article is to provide general information on yeast and mold, and to explain why TYMC is an important indicator in determining cannabis safety.

Yeast & Mold

Photo credit: Steep Hill- a petri dish of mold growth from tested cannabis

Yeast and mold are members of the fungi family. Fungus, widespread in nature, can be found in the air, water, soil, vegetation and in decaying matter. The types of fungus found in different geographic regions vary based upon humidity, soil and other environmental conditions. In general, fungi can grow in a wide range of pH environments and temperatures, and can survive in harsh conditions that bacteria cannot. They are not able to produce their own food like plants, and survive by breaking down material from their surroundings into nutrients. Mold cannot thrive in an environment with limited oxygen, while yeast is able to grow with or without oxygen. Most molds, if grown for a long enough period, can be detected visually, while yeast growth is usually detected by off-flavor and fermentation.

Due to their versatility, it is rare to find a place or surface that is naturally free of fungi or their spores. Damp conditions, poor air quality and darker areas are inviting environments for yeast and mold growth.

Cannabis plants are grown in both indoor and outdoor conditions. Plants grown outdoors are exposed to wider ranges and larger populations of fungal species compared to indoor plants. However, factors such as improper watering, the type of soil and fertilizer and poor air circulation can all increase the chance of mold growth in indoor environments. Moreover, secondary contamination is a prevalent risk from human handling during harvest and trimming for both indoor and outdoor-grown cannabis. If humidity and temperature levels of drying and curing rooms are not carefully controlled, the final product could also easily develop fungi or their growth by-product.

 What is TYMC?

TYMC, or total yeast and mold count, is the number of colony forming units present per gram of product (CFU/g). A colony forming unit is the scientific means of counting and reporting the population of live bacteria or yeast and mold in a product. To determine the count, the cannabis sample is plated on a petri dish which is then incubated at a specific temperature for three to five days. During this time, the yeast and mold present will grow and reproduce. Each colony, which represents an individual or a group of yeast and mold, produces one spot on the petri dish. Each spot is considered one colony forming unit.

Why is TYMC Measured?

TYMC is an indicator of the overall cleanliness of the product’s life cycle: growing environment, processing conditions, material handling and storage facilities. Mold by itself is not considered “bad,” but having a high mold count, as measured by TYMC, is alarming and could be detrimental to both consumers and cultivators. 

Aspergillus species niger
Photo: Carlos de Paz, Flickr

The vast majority of mold and yeast present in the environment are indeed harmless, and even useful to humans. Some fungi are used commercially in production of fermented food, industrial alcohol, biodegradation of waste material and the production of antibiotics and enzymes, such as penicillin and proteases. However, certain fungi cause food spoilage and the production of mycotoxin, a fungal growth by-product that is toxic to humans and animals. Humans absorb mycotoxins through inhalation, skin contact and ingestion. Unfortunately, mycotoxins are very stable and withstand both freezing and cooking temperatures. One way to reduce mycotoxin levels in a product is to have a low TYMC.

Aspergillus flavus on culture.
Photo: Iqbal Osman, Flickr

Yeast and mold have been found to be prevalent in cannabis in both current and previous case studies. In a 2017 UC Davis study, 20 marijuana samples obtained from Northern California dispensaries were found to contain several yeast and mold species, including Cryptococcus, Mucor, Aspergillus fumigatus, Aspergillus niger, and Aspergillus flavus.3 The same results were reported in 1983, when marijuana samples collected from 14 cannabis smokers were analyzed. All of the above mold species in the 2017 study were present in 13 out of 14 marijuana samples.4

Aspergillus species niger, flavus, and fumigatus are known for aflatoxin production, a type of dangerous mycotoxin that can be lethal.5 Once a patient smokes and/or ingests cannabis with mold, the toxins and/or spores can thrive inside the lungs and body.6, 7 There are documented fatalities and complications in immunocompromised patients smoking cannabis with mold, including patients with HIV and other autoimmune diseases, as well as the elderly.8, 9, 10, 11

For this reason, regulations exist to limit the allowable TYMC counts for purposes of protecting consumer safety. At the time of writing this article, the acceptable limit for TYMC in cannabis plant material in Colorado, Nevada and Canada is ≤10,000 CFU/g. Washington state requires a mycotoxin test.12 California is looking into testing for specific Aspergillus species as a part of their requirement. As the cannabis industry continues to grow and advance, it is likely that additional states will adopt some form of TYMC testing into their regulatory testing requirements.

References:

  1. https://www.colorado.gov/pacific/sites/default/files/Complete%20Retail%20Marijuana%20Rules%20as%20of%20April%2014%202017.pdf
  2. http://laws-lois.justice.gc.ca/eng/acts/f-27/
  3. https://www.ucdmc.ucdavis.edu/publish/news/newsroom/11791
  4. Kagen SL, Kurup VP, Sohnle PG, Fink JN. 1983. Marijuana smoking and fungal sensitization. Journal of Allergy & Clinical Immunology. 71(4): 389-393.
  5. Centre for Disease control and prevention. 2004 Outbreak of Aflatoxin Poisoning – Eastern and central provinces, Kenya, Jan – July 2004. Morbidity and mortality weekly report.. Sep 3, 2004: 53(34): 790-793
  6. Cescon DW, Page AV, Richardson S, Moore MJ, Boerner S, Gold WL. 2008. Invasive pulmonary Aspergillosis associated with marijuana use in a man with colorectal cancer. Diagnosis in Oncology. 26(13): 2214-2215.
  7. Szyper-Kravits M, Lang R, Manor Y, Lahav M. 2001 Early invasive pulmonary aspergillosis in a leukemia patient linked to aspergillus contaminated marijuana smoking. Leukemia Lymphoma 42(6): 1433 – 1437.
  8. Verweii PE, Kerremans JJ, Voss A, F.G. Meis M. 2000. Fungal contamination of Tobacco and Marijuana. JAMA 2000 284(22): 2875.
  9. Ruchlemer R, Amit-Kohn M, Raveh D, Hanus L. 2015. Inhaled medicinal cannabis and the immunocompromised patient. Support Care Cancer. 23(3):819-822.
  10. McPartland JM, Pruitt PL. 1997. Medical Marijuana and its use by the immunocompromised. Alternative Therapies in Health and Medicine. 3 (3): 39-45.
  11. Hamadeh R, Ardehali A, Locksley RM, York MK. 1983. Fatal aspergillosis associated with smoking contaminated marijuana, in a marrow transplant recipient. Chest. 94(2): 432-433.
  12. http://apps.leg.wa.gov/wac/default.aspx?cite=314-55-102