Last updated on September 9, 2026 · Originally published February 18, 2021
Content provided by Byers Scientific, a manufacturer of odor-control and emissions-assessment systems.
Why understanding a canopy’s emission profile matters for odor control
Community complaints about odor from cannabis operations are at an all-time high nationwide — due in part to cultivators’ continued reliance on HVAC systems that were never engineered for cannabis odor control. Byers Emissions Analysis, led by emissions scientists Dr. Alex Guenther and Dr. Will Vizuete, approaches the problem from the measurement side: profiling what a facility’s plants actually emit before sizing any mitigation.
Cannabis odor and emissions remain an under-researched field. What is known: odor is typically strongest during flowering, and plants emit at the highest concentrations during agitation — harvesting and processing. Cannabis plant emissions contain more than 200 unique molecules, spanning monoterpenes, sesquiterpenes, thiols, and other compounds. Like other recent studies, the Byers team’s research has identified 3-methyl-2-butene-1-thiol as a potential contributor to the most recognizable cannabis odor — though their leaf-enclosure studies have found many other thiols emitted by the plant, suggesting no single molecule produces the “skunk-like” smell on its own.
How a facility emissions assessment works
Each assessment begins by measuring individual strains and their emissions using the leaf enclosure method, which determines the types and quantities of site-specific terpenes and other biogenic volatile organic compounds (BVOCs). Facility air samples supplement the enclosure data. Samples are analyzed by gas chromatography–mass spectrometry (GC-MS), and the resulting data yields emissions factors per strain — feeding what Byers describes as a first-of-its-kind cannabis emissions inventory for air quality, odor, and terpene drift. Notably, their studies have shown significant variability in the rate and composition of BVOC emissions across, and even within, cannabis strains.
From strain count, plant count, life stage, and estimated plant weight, the team quantifies a site-specific gas-phase emission rate.
Why measurement precedes mitigation
Standard ambient air sampling reveals only a fraction of a canopy’s actual emissions; enclosure studies with GC-MS analysis measure the true emissions profile, which then anchors odor-mitigation planning. The emission data feeds a mass-balance calculation that determines how much molecular filtration capacity a space actually requires — for example, a 225,000 ft³ cultivation space working out to roughly 12,000 cfm, or about three air exchanges per hour. That precision matters in both directions: undersized systems let odor molecules escape, while “over-scrubbing” can negatively affect plant health.
For cultivators facing licensing requirements or community complaints, a measured emissions profile turns odor control from guesswork into engineering.
More on Byers Scientific’s emissions assessment services is available here.
