Carbon dioxide enrichment is a critical component for indoor cannabis growers. CO2 - along with water and light - are necessary components of photosynthesis, the biological reaction that results in plant growth.
However, what indoor growers may not realize is that high levels of CO2 can also be dangerous. A sealed indoor grow room can trap lethal levels of CO2 that can lead to poor respiratory health, incapacitation, and even death.
CO2 Generators in Greenhouses
For decades greenhouses have used CO2 generators that burn fossil fuels to generate carbon dioxide. Recent trends in enrichment have moved growers away for generators and in to CO2 enrichment for two reasons: burning fossil fuels is an incomplete process leaving residues in the plants, and, the low cost and neutral effects of CO2 make the gas cost effective and easy to control.
CO2 Enrichment Today
Indoor cannabis growers have solved the problem of burners by switching to compressed cylinders or bulk tanks of liquid CO2. A CO2 level controller maintains the required carbon dioxide levels for the grower. When CO2 levels drop, a tank regulator with a solenoid valve is opened and releases CO2 to enrich the grow space.
Because the CO2 level is precisely measured and maintained, a well-designed system can save hundreds or even thousands of dollars in gas costs. Our customers report a 30-40% reduction in gas usage when they move to a liquid CO2-based system.
The introduction of CO2 must be done in a precise, controlled, calculated, well planned manner. Simply opening a valve on a CO2 tank at one end of the room and hoping that the gas will disperse evenly is not a good plan.
If you are getting into indoor growing, you should find an experienced HVACR contractor to design a system for you. You may have to spend some time educating them on growing and the need for CO2, but their experience with precise air exchange rates can create a safe and effective system. Installing a system with correct CFM air flows, pressures, valves, and safety devices are critical to success.
As Dave, a grower in Denver told us, “Having the correct CO2 system is as important to me as the lights and even the plants. I might as well throw money down the drain without the right CO2 system.”
Sealed Grow Rooms and CO2 Safety
Unlike greenhouses used for flower and vegetables, cannabis growers are moving to sealed grow rooms. The advantages are:
- Better control of temperature, water, nutrients
- Control of plant diseases, molds, pests
- Regulate precise CO2 levels
- Minimize liquid CO2 costs
- Create a secure environment for growing
The downside of a sealed and secure grow room is that it creates a potential safety hazard for workers. A leak in the CO2 enrichment system is no different than a leak in any bar or restaurant that uses liquid CO2 to carbonate soft drinks.
Because CO2 is heavier than air or oxygen it will “pool” at the floor, then rise up until it fills a room. This drives the oxygen level in an enclosed space down to levels that can cause a person to pass out or even die. Even a small leak in a supply hose or a faulty regulator can cause CO2 levels to rise to the point that the air in the room becomes deadly. The increased use of pressurized liquid CO2 has resulted in several near death experiences. As a result, local fire marshals and building inspectors have begun to require the monitoring of CO2 for safety in legal cannabis growing operations.
For example, in states like Oregon and California local Fire Marshals now require licensed cannabis operations to install CO2 monitors for safety in each grow room. The device is meant to be set at levels that will ensure that asphyxiation does not occur. Other localities require strobe lights and multiple alarm levels.
In almost every state and municipality there are new laws regulating the use of stored CO2. However, even if you are growing recreational marijuana, if you grow and use compressed CO2 in an enclosed space (like a basement) it makes sense to invest in a CO2 safety monitor.
Grow Room CO2 Safety Monitor
For cannabis growers who use liquid CO2 enrichment we recommend our Remote CO2 Storage Safety 3 Alarm.
- Wired CO2 Monitor & Remote Display
- Designed to Meet All Local Fire Codes
- Meets NFPA, IFC, and NBIC Requirements
- Meets OSHA and NIOSH TWA Standard
It meets all local codes, installs in minutes, and provides protection for you and any staff around stored CO2. Learn more about the grow room CO2 safety monitor.