As the market for medicinal cannabis products grows in response to research that suggests it is effective for relieving the symptoms of chronic illnesses, the industry will need to respond to safety concerns surrounding the production of cannabis extracts. States like Oregon that have legalized cannabis for medicinal and recreational use have experienced a rise in the number of injuries from dangerous solvent explosions. In one 16-month period, 17 people were sent to a Portland burn unit with injuries from butane-fueled blasts. This experience has been replicated across states that have legalized or decriminalized the use of cannabis.

Even through many of these states also require licenses for producers, they still misunderstand the risks associated with using hydrocarbon solvents. Hydrocarbon gases like butane can quickly fill enclosed spaces where something as ordinary as static electricity or a pilot light can ignite the fumes, producing fireballs and explosions that destroy infrastructure and seriously injure people. With education and access to safety equipment, states and the industry as a whole can begin to better manage the hazards of a budding cannabis market.



The cannabis industry in the United States is rooted in growing flowers and buds that are ultimately smoked by consumers, but the market for cannabis extracts is expanding as researchers are beginning to uncover the palliative qualities of the cannabis plant. Cannabis is widely recognized as a treatment for symptoms of multiple sclerosis, Chron’s disease, and glaucoma. THC and CBD—two of the active ingredients in cannabis—are also used to counter nausea in cancer patients undergoing chemotherapy and poor appetite/weight loss caused by chronic illnesses such as nerve pain and HIV. Laboratories around the world have also discovered that cannabis acts as a neuroprotective compound in the brain. Patients who have experienced strokes, emotional or traumatic brain injuries can potentially benefit from cannabinoid treatments. Even as new discoveries emerge, most researchers agree that more studies are necessary to fully understand how cannabis affects bodily systems.

With mounting evidence in support of a wide array of medicinal benefits, the staunch resistance from the Drug Enforcement Administration (DEA) bewilders many in the industry. According to the DEA, cannabis remains a Schedule I controlled substance—with no medicinal use, a high potential for abuse, and a lack of accepted safety standards for use—though the federal government has begun to authorize research into its potential uses. Groups like the Marijuana Policy Project have been indispensible in pushing for reform that would open up the marketplace to more research initiative and better regulation to ensure a more robust safety culture for the cannabis community.

In all, 22 states and the District of Columbia have enacted medical cannabis laws that authorize and regulate its use, but the disconnect between state legalization/decriminalization efforts and continued federal criminalization has raised safety concerns amongst producers, consumers, and researchers. Cannabis extracts contain 40—80% THC and are drastically more potent than marijuana buds, but we are yet to fully understand the complex chemical composition of cannabis.

With this limited information, few states currently require dispensaries to provide health warnings, ratings for potency and certification that the product meets safety standards. The growth of laboratories that perform these services indicates that industry demand favors better safety options than are currently required. According to industry experts like Michael Bishop, Director of Applied Markets for Heidolph North America, “there are going to be increasing requirements for high purity and reproducibility” of extracts, both as a medical necessity and a market imperative. For cannabis extracts to become a more readily accepted and viable treatment option, it is imperative for the industry to adopt standards regulating the consistency, safety, and efficacy of extracts.



Quality control and safe processing of cannabis begin with cultivation, the management of moisture levels, reducing contamination by pesticides, and it extends through the extraction process where working with volatile substances makes personnel protection paramount. While the most important control in the cultivation of cannabis is the employment of good agricultural practices—which provide the best methods for soil and water use to prevent biological and toxic contamination—the risk for contamination extends to handling and processing. This means that it is imperative for producers to ensure the purity of their product after it has been harvested and properly dried.

From cultivation to production and consumption, the continued viability of the cannabis industry depends upon adopting standards and methods for bringing new products to market with the assurance that they are free of residual solvents, pesticides and other biological contaminants, like mold or E. coli. Equipping growers and producers with the means to reduce contamination that occurs during the drying and extraction process is the goal of Flow Sciences’ new partnership with the cannabis industry. Safe processing of cannabis extracts also means ensuring proper ventilation systems are in place to reduce the risks associated with volatile solvents like butane.

Flow Sciences’ team of industrial engineers design workstations and enclosures that reduce product contamination and maximize protection for professionals who work with volatile substances like those used in cannabis processing. All of our products are engineered and manufactured at our corporate headquarters in Leland, NC and are backed by our sophisticated design process and award-winning excellence in engineering, including 11 U.S. Government patents. We have been working with pharmaceutical companies, research and development laboratories, manufacturing, and production facilities for 30 years. Our task-specific designs are dynamic solutions that are adaptable to our clients’ workflow and specific needs.

Flow Sciences was one of the first companies in the U.S. to use computational fluid dynamics (CFD) in drafting our enclosures to ensure optimum airflow. Our engineers use CFD algorithms to simulate fluid flows and interactions within contained spaces. This enables us to predict and control airflow through design, which we then test in our state-of-the-art laboratory. Working closely with our clients to mimic real-world applications, we develop testing protocols based on the intended use of our enclosures and measure them against industry-accepted standards to ensure proper containment. We have designed, manufactured, and tested over 13,000 enclosures, generating a wealth of data on situational flow dynamics, which allows us to control for consistency, safety, efficacy, and overall quality.

As the cannabis market grows and becomes simultaneously more regulated and competitive, third-party potency testing to meet state statues will intersect with the need to analyze products and develop cannabinoid profiles through formal sampling protocols. With three decades of experience and expertise in developing containment solutions for product and personnel protection, Flow Sciences is ideally positioned to partner with producers and third-party testing facilities in order to address issues of safety and quality in cannabis processing.



The essential oils of cannabis plants are found in the trichomes—or, the crystalline structures on the outside of the marijuana buds. The goal of cannabis extraction is to preserve these trichomes because they house the medically valuable cannabinoids (THC, CBD) and terpenoids (Myrcene, Linalool). There are various methods of processing cannabis, including dry sieving, but the principle methods of extraction involve the use of CO2 or highly volatile, carbon-based solvents to isolate the plant’s active ingredients. While CO2 offers producers an organic means of extraction and a higher degree of control, it also takes longer and is more expensive than using butane—or propane, hexane, acetone, or ethanol—which produces higher volumes and finer grain results.

Because trichomes are lipid and alcohol soluble, extraction oftentimes involves the use combustible solvents and necessitates laboratory equipment like rotary evaporators (i.e., rotovaps) to isolate cannabinoids and therapeutic terpenoids from cannabis plants. Rotovaps work by coupling a low-heat distillation process with a vacuum system, enabling producers to control for both heat and pressure and extract different components at varying intervals. While the use of rotovaps enables the extraction process and the production of valuable medicinal products, the use of volatile carbon-based solvents increases the risk of fire and explosions if there is no care taken to properly ventilate the workspace.


Ensuring safe extraction methods oftentimes requires the use of fume hoods, like the Saf T Flow™ Fume Hood designed by Flow Sciences to specifically protect personnel from chemical vapors generated during processes like distillation. The Saf T Flow™ system is a ventilated enclosure that works by containing vapors and fumes and continuously channeling airflow away from personnel and the workspace before being directed through a house exhaust system. Saf T Flow™ systems can safely remove volatile fumes generated during cannabis extraction by controlling airflow through design.

Flow Sciences’ Saf T Flow™ Fume Hood is designed with an Overlapping Sash Bypass (OSB) system of overlapping front panels that allow for varied airflow options depending on whether the sash is fully raised, partially open, or closed. This ensures that the Saf T Flow™ Fume Hood consistently directs airflow away from personnel and to exhaust systems regardless of air volume. The Saf T Flow™ Fume Hood can effectively eliminate vapors from the cannabis extraction-distillation process and reduce the risk of fires and/or explosions associated with the use of solvents like butane.


  • Saf T Flow™ Fume Hoods have been tested from 100 FPM down to 60 FPM—simulating the full range of sash options—with ASHRAE 110 containment equipment, and have proven Breathing Zone Containment at or below 0.005 ppm.
  • The Saf T Flow™ Fume Hood Series features a unified design structure to maximize simplicity in lab planning, layout, and HVAC coordination. Saf T Flow ™ hoods accommodate most low-flow exhaust options without requiring expensive retrofits.
  • Saf T Flow™ hoods are designed to reduce the volume of air necessary to maintain containment with an OSB system that reduces the energy costs associated with hoods that use constant, high-volume airflow.



The risks associated with the use of solvents for the production of hash oil extend beyond their volatility alone. According to a recent study in the Journal of Toxicological Sciences, cannabis concentrate could carry toxic solvents as residue from the extraction process, which may have long-term effects on exposed consumers.

Pesticide use is regulated by the Environmental Protection Agency, which has yet to approve pesticides for use on cannabis. In the absence of further guidance from the United States Department of Agriculture and the Food and Drug Administration, states have begun to issue guidelines and propose regulations for the cultivation, extraction, and distribution of cannabis to control for potential biological and toxic contamination of cannabis products. Washington requires that solvent-based extracts using hydrocarbon gases must be of at least 99% purity, and the products must also undergo a residual solvents test. Post-production testing of cannabis extracts for residual solvents and other biological or toxic contamination is performed by third-party laboratories.

Guidelines governing the presence of contaminants vary, but states that have decriminalized medicinal cannabis have consistently moved towards requiring third-party analysis of cannabis products. For these third-party testing facilities, the scope of analysis broadly varies and is further complicated by a lack of exposure data and the limits of analytical chemistry labs that can only certify the absence of certain contaminants, like pesticides, down to a limit of quantification. As a result, cannabis screening requires testing for both the presence and, more importantly, the absence of pesticides in order to guarantee the accuracy and reproducibility of results.

The Oregon Health Authority (OHA) convened a Technical Expert Working Group in 2015 to qualify public risks that arise specifically during the cultivation and processing of cannabis for medicinal and recreational consumption. Based on their research, the OHA established action levels that would trigger state agencies to prohibit the sale and distribution of cannabis products that were found to exceed reasonably safe levels of contamination. In all, they identified a total of three biological agents, 59 pesticides, and 45 solvents that pose health risks to the general public, and they recently began to require testing for all medical cannabis.

These complex-testing processes can be handled by a combination of screening techniques. Due to their relative cost, the most commonly used screening technologies for insecticides, herbicides, and pesticides in the cannabis industry are immunoassays and broad spectrum field tests, but these non-standardized methodology are at a high risk of not detecting pesticide residues.

Gas chromatography (GC) remains the primary methodological technique used for federal regulatory purposes, which is now being adopted by emerging cannabis testing laboratories across the country. GC and its laboratory cousins—like liquid chromatography (LC)—rely on the vaporization of solvents in order to separate, identify, and quantify the components of any mixture. Laboratories are also adopting alternative methods of analysis that do not rely on heat in order to vaporize samples because heat changes the structure of acidic cannabinoids and certain pesticides, rendering them nearly impossible to detect. High-Performance Liquid Chromatography (HPLC) is emerging as a non-destructive alternative to GC and LC analysis methods because it ensures more precise analysis of the cannabinoid components of cannabis.

Though it is nondestructive, the chromatographic process uses methanol and chloroform to prepare extract samples for cannabis testing, and the process itself produces fumes that are harmful to laboratory/dispensary personnel. Whether GC, LC, or HPLC is used to analyze cannabis extracts, laboratories and dispensaries should ensure that they understand and employ proper containment techniques.

Local Exhaust Ventilation (LEV) Enclosures

Similar to fume hoods, Flow Sciences’ LEV enclosures work by directing airflow away from personnel and across the workspace through the use of front airfoils and rear plenums. The Benchmark LEV enclosure is engineered with the same attention to airflow control as our fume hoods because the most common risk in any laboratory that utilizes solvents is daily exposure to hazardous vapors. The Benchmark LEV goes through comprehensive assessment from CFD design control and ASHRAE testing to ensure that laboratory personnel are not inhaling potentially damaging vapors from cannabis testing.

LEV enclosures are also designed to be compatible with existing house exhaust systems, which allows laboratories to replace outdated or underperforming equipment without needing to remodel their workspace. LEVs are ideal for scalable operations. Laboratories can couple two or more LEV units in order to accommodate large-scale processes without unduly increasing air change rates. While fume hoods are the standard containment solution for cannabis extraction operations that utilize large rotovaps, a laboratory equipped with LEV enclosures can conduct multiple, separate experiments simultaneously.

Benchmark LEV Enclosure

  • Through the use of front airfoils and rear plenums, LEV Series enclosures provide ideal protection from chemical vapors generated by the use of rotary evaporators and analytical chromatography instruments.
  • The LEV Series is designed specifically for laboratory equipment with a dual-hinged front loading sash and side access doors. LEV enclosures also feature a lightweight structure that makes for easy movement in dynamic laboratory spaces, and they come in standard dimensions tailored to fit industry leading equipment.
  • LEV enclosures are the fume hood alternative, providing laboratories with the same, unparalleled protection from harmful fumes and vapors while accommodating small-scale operations.

Cannabis testing that utilizes volatile solvents like methanol also place laboratory personnel at risk for exposure to fires. With this in mind, Flow Sciences developed a Fire Safety LEV enclosure constructed with a flame-retardant polypropylene superstructure and glass viewing panels. The Fire Safety LEV can be equipped with a built-in Fire Suppression system to quickly and effectively extinguish potential fires directly at the source of ignition.

Fire Safety LEV Enclosure

  • Fire Safety LEVs are constructed from flame-retardant polypropylene and glass to ensure that potential laboratory fires are contained at the source.
  • Fire Suppression. Flow Sciences worked with fire protection specialists to design a fire trigger that detects and automatically extinguishes fires from inside the enclosure.
  • Fire Safety LEVs are designed to accommodate large-scale operations that require the superior safety of fume hood technology.


As more states moving to legalize and decriminalize the use of cannabis, industry growth will fuel the start of more analytical laboratories committed to testing cannabis products for safety. Beyond testing cannabis for the presence of contaminants, laboratories will also heed the market imperative to develop advanced cannabinoid profiles so that physicians and consumers can make informed decisions about treatment options.

Laboratories and dispensaries that use CG or LC to identify the components of cannabis extracts can couple those methods with a conventional detector or mass spectrometry (MS) to develop more complete cannabinoid profiles. Coupling analytical processes goes beyond testing for the presence of contaminants and is more in line with a developing market mentality regarding cannabis packaging and quality assurance. These Extract Elite are on the forefront of an industry seeking to legitimize cannabis by creating complete profiles that grow the industry by creating informed stakeholders.

Cannabinoid profiles offer the most accurate data concerning the potency, THC-CBD ratio and purity of cannabis extracts, which are invaluable to physicians, patients, and dispensaries that need to make informed decisions about the prescription and use of therapeutic cannabis extracts. In an effort counter the cost of additional testing by increasing capacity, cannabis industry leaders are utilizing faster, more capable, and single-process solutions that use triple quadrupole and ultrafast mass spectrometers (UFMS). These highly efficient analytical tools still require the same safety precautions as their more traditional counterparts, which can also be contained with a Flow Sciences’ LEV Series enclosure.

Instead of simply assuring customers that extracts are free of contaminants, the Extract Elite are partnering with laboratory and containment experts, like the engineering team and Flow Sciences, to develop formal sampling protocol using the best analytical tools and containment solutions to guarantee safe consumption, potencies, and constituent concentrations that adhere to standards like those put out by the FDA concerning safety, consistency, and efficacy.

As the cannabis market continues to develop and become more competitive, the Extract Elite will emerge as providers of more than products. By expanding the boundaries of product assurance to include cannabis profiling, they will deepen the industry’s commitment to quality and allow stakeholders to make more informed decisions about the prescription and consumption of cannabis products.



By partnering with Flow Sciences, the Extract Elite can create a safety climate that recognizes and responds to risks, and they can further encourage industry growth and vibrancy by establishing a level of quality assurance hat guarantees both product protection and analytical reproducibility. More than any other containment specialists, Flow Sciences offers our partners expertise that is rooted in a commitment to innovation. The advantage of seeking a Flow Sciences solution is our ability to anticipate industry needs by fostering a dedication to complete safety quality assurance, and excellent performance.


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