Tag Archive | "hazardous gases"

Monitoring of CO, CO2 and Combustible Gases in Indoor Grow Ops

With the recent legalization of marijuana in many North American regions, the cannabis cultivation industry is booming. Greenhouses and other indoor grow rooms provide a structure for growing plants in a controlled environment but can also pose potential hazards to human health. To create favourable growing conditions, reliable heating, cooling and ventilation must be used. Heating may be supplied by sunlight, natural gas, propane gas, fuel oil, wood or electricity. Gas powered equipment may be a source of carbon monoxide if not properly maintained and serviced. Grow lights emit a great deal of heat and can cause combustible gases to ignite. Cooling of the facility is often done by a ventilation system. But there may also be an air conditioning system, which could be a source for refrigerant leaks. Current practices for the commercial cultivation of marijuana and industrial hemp uses Carbon dioxide (CO2) enrichment to increase plant growth and development either using cylinders of liquefied compressed gas or a CO2 generator. CO2 displaces oxygen and can cause an asphyxiation hazard.


Two gas detectors should be mounted inside the furnace room – one for monitoring potential leaks in the pipes supplying the gas to the furnace, and the other monitoring carbon monoxide levels generated by the furnace. A well maintained, efficiently burning furnace produces very small amounts of CO, but a dirty, inefficient burning one can product deadly amounts. To monitor the CO levels, an LPT-M-TCO-R should be mounted inside the furnace room at the “breathing zone” (4 -6 ft from the floor). Connected the the LPT-M-TCO-R would be a remote sensor. If the furnace uses propane, an ESH-A-C3H8-100 remote sensor with an internal propane sensor would be used, mounted 6 inches off the finished floor, close to the pipes suppling the gas to the furnace. If the furnace uses natural gas, an ESH-A-CCH4-100 remote sensor with an internal methane sensor should be used instead, mounted 6 inches from the ceiling above the pipes supplying the gas.


Inside the room, should be an audible/visual alarm device such as the RSH-24V-R Remote Strobe/Horn. Mounted outside the door of the furnace room would be a QCC Quad Channel Controller. If there are additional entrances to the room, each should have a remote visual/audible alarm device outside the door. Inside the grow room there should be an AST-IS6 carbon dioxide gas detector mounted in the “breathing zone” (4 – 6 ft from the floor) to provide continuous monitoring of CO2 levels. This is especially important if a CO2 enrichment practice is used. The AST-IS6 can be factory set with a range of 0 – 5,000 ppm and one device covers approximately 743 sq m (8,000 sq ft).


The LPT-M and AST-IS6 will communicate with QCC, which in turn will display their gas level readings, and in the event of a leak / high gas concentration, will provide an audible alarm and control equipment such as the ventilation system, shut off the furnace, trigger the other remote horn/strobe devices or other set responses as configured using its 3 internal relays. The QCC can be ordered with an optional data logging package and it can be configured to communicate with a Building Automation System. The aforementioned gas detectors/sensors are housed in water / dust tight enclosures, and are IP54 rated with the factory installed splash guard, providing protection for the equipment in wet areas.


Typical Indoor Grow Op Monitoring System:



About Critical Environment Technologies Canada Inc.

Critical Environment Technologies Canada Inc. is a leading equipment manufacturer for commercial and industrial gas detection applications. We are dedicated to designing, developing and servicing hazardous gas detection systems for a wide range of applications that require monitoring of refrigerants, TVOCs, combustible and toxic gases. CETCI’s products are sold through a worldwide network of authorized distributors. Our knowledgeable Regional Sales Managers are experienced with many application scenarios, including commercial, institutional, municipal and light industrial markets worldwide. Areas of specialization include car parks, refrigeration plants, commercial swimming pools, water purification, including wastewater treatment facilities, ice arenas, wineries and breweries, schools and many more.

For suggestions on gas detection systems, indoor air quality monitors and calibration, please visit


Posted in Applications, EducationalComments Off on Monitoring of CO, CO2 and Combustible Gases in Indoor Grow Ops

A Dual Channel Gas Detector for Monitoring Hazardous Gases in the Workplace

Critical Environment Technologies Canada Inc, (CETCI) offers strategic and reliable gas detection solutions for many applications. Our DCC Dual Channel Controller is an ideal fixed gas detection system for monitoring indoor air to protect workers from exposure to unhealthy levels of combustible, toxic and refrigerant gases, oxygen deficiency, and volatile organic compounds in the workplace.

The potential for exposure to hazardous gases is a concern in many workplace environments. In fact, every workplace must meet local (provincial/state, COOHS/OSHA, etc.) health and safety standards for hazardous gas exposure during working hours. To ensure the safety of the workers, equipment, and the facility, areas presenting a gas hazard should be monitored by gas detectors. In the larger, open areas, a fixed gas detection system is suitable; in confined spaces that workers enter and where gas may be present, portable gas detectors are more appropriate.

Commercial buildings that share a warehouse with manufacturing and/or service work in the back and offices in the front are a prime place for harmful gases and vapours to be present in the entire workplace area.  Airports, hotels, restaurants, supermarkets, shopping malls, manufacturing plants, food processing plants, vehicle repair shops, wineries, breweries and many more are all examples of workplaces where hazardous gases are used or produced onsite.

CETCI’s DCC Dual Channel Controller offers a fixed, continuous hazardous gas monitoring solution with two gas channels, two programmable relays, two 4-20 mA outputs and one configurable 4-20 mA input, an internal audible alarm, an LCD display with LED indicators and a password protected menu system. The two gas channels can be configured with one or two internal gas sensors, one internal and one remote gas sensor or one remote gas sensor, depending on the application requirements. The internal gas sensor options include toxic gases such as carbon monoxide, nitric oxide, nitrogen dioxide, oxygen, etc. The remote sensor options include refrigerants, TVOCs and combustible gases such as hydrogen, methane and propane. The DCC can also be connected to a remote 4-20 mA transmitter/gas detector such as our AST-IS (CO2), ART (IR refrigerants), LPT (CO or NO2) or LPT-A (various gases). All of our gas detectors come standard in a water/dust tight enclosure with a copper coated interior to reduce RF interference.

Optional, value added features for the DCC include an extra loud door mounted buzzer for noisy environments, a top mounted strobe, an internal heater for cold environment applications, and a door mounted water tight buzzer and splash guard for wet or spray down environments.

The DCC Dual Channel Controller conforms to CSA, UL, CE, FCC and IP54 standards.


About Critical Environment Technologies Canada Inc.

Critical Environment Technologies designs and manufacturers indoor air quality and fixed gas detection systems including self-contained systems, controllers and transmitters (analog, digital and wireless). Applications include commercial HVAC, institutional, municipal and light industrial markets worldwide. Many of these applications are for vehicle exhaust, but areas of specialization include refrigeration applications, food processing plants, manufacturing plants, wastewater treatment plants, fisheries, wineries/breweries, pulp and paper mills, recreational facilities, bakeries, greenhouses, and many more.

For more information about our products, check out our website at www.critical-environment.com or to discuss a tailored gas detection solution for your application, contact us at 1-877-940-8741.


Posted in Controllers, Products, Self ContainedComments Off on A Dual Channel Gas Detector for Monitoring Hazardous Gases in the Workplace

CETCI’s CXT Explosion Proof Transmitter

Our CXT Explosion Proof Transmitter delivers reliable, accurate monitoring of toxic or combustible gases in potentially explosive and harsh environments and meets CSA and ATEX standards for use in hazardous locations where the potential for explosions is extremely high.

Click here to read more…


Posted in Products, TransmittersComments Off on CETCI’s CXT Explosion Proof Transmitter

What is the Difference Between Explosion Proof and Intrinsically Safe Gas Detectors?

It only takes a spark to start a fire or cause an explosion, especially when flammable gases or vapours are present under the right conditions. There are industries that operate in these types of hazardous environments where the potential for explosions is extremely high, such as chemical plants, oil refineries, paint shops, cleaning facilities, tanks and loading facilities for flammable gases, liquids and solids. OSHA defines hazardous locations as:

Areas where flammable liquids, gases or vapors or combustible dusts exist in sufficient quantities to produce an explosion or fire. In hazardous locations, specially designed equipment and special installation techniques must be used to protect against the explosive and flammable potential of these substances.

Two types of specially designed equipment for use in hazardous locations are explosion proof and intrinsically safe.

Explosion proof is a protection technology that guarantees the housing or enclosure has been designed and constructed in such a way that it is capable of containing, controlling and venting any possible flash or explosion. Enclosures of this kind are typically made of stainless steel or cast aluminum and are of an appropriate mass and strength that they will safely contain an explosion if flammable gases or vapours should penetrate the housing and the internal electrical components or wiring should cause an ignition. The amount of power to or from the device is not of concern.

Intrinsically safe is an explosion protection technique that ensures that the electrical circuit and its wiring is engineered in such a way that it is not capable of releasing enough energy, or producing a high enough temperature under any condition and thus is not able to cause an ignition of itself or the surrounding area. This specifically designed equipment does not require a special enclosure or housing. Instead, the amount of power the device has is typically controlled through the use of intrinsic safety barriers and as a result, this type of equipment can be used only for very low power applications.

Gas detectors for hazardous location applications must meet strict codes and standards and can be built as either explosion proof or intrinsically safe. Intrinsically safe gas detectors are very common in Europe and explosion proof is the more commonly used method in North America for fixed gas detection systems. With the rugged housing to withstand harsh environments and no limits on the types of sensors, the explosion proof gas detector can be used in a wider range of applications and in particular, for applications that require high power.


Explosion Proof Gas Detector Intrinsically Safe Gas Detector
Protection Method Contains and controls the explosion, does not prevent an internal explosion Prevents an explosion, does not contain an explosion
Enclosure Stainless steel or cast aluminium Standard
Size, Weight Large, heavy, often bulky Compact, light
Power Requirements Power is not controlled, operates at normal power levels Power is controlled, operates on low power levels
Installation Difficult: heavy, bulky, requires heavy conduit and seals Easy: small and does not require expensive accessories
Maintenance & Calibration Non-intrusive calibration may be done without disconnecting power. Power must be disconnected if opening the device. Non-intrusive calibration may be done without disconnecting power. Power must be disconnected if opening the device.
Types of Sensors Electrochemical, infrared, combustible/catalytic or PIDs Electrochemical (low current sensors only)
Application Examples Oil Refineries, Drilling rigs on oil fields, Municipal Treatment Plants, Chemical Storage Rooms, Loading facilities for flammable gases, liquids and solids


Definition of Hazardous Locations in North America

ATEX Certification for products used in hazardous locations in Europe


For suggestions on gas detection systems, indoor air quality monitors and calibration, please visit



Written by Rebecca Erickson

Allen-Bradley, Rockwell Automation (October 2001) Class/Division Hazardous Location. Retrieved from http://literature.rockwellautomation.com/idc/groups/literature/documents/wp/800-wp003_-en-p.pdf
Bob Svacina and Brad Larson, Turck Inc. (April 2000). Understanding Hazardous Area Sensing. Retrieved from http://www.parrinst.com/wp-content/uploads/downloads/2011/06/Svacina-Larson_Understanding-Hazardous-Area-Sensing_Intrinsic-Safety.pdf
CorDEX Instruments Ltd. (2010). Intrinsically Safe or Explosionproof? Understanding the technology. Retrieved from http://www.transcat.com/media/pdf/cordex-is-explosion-proof.pdf
RKI Instruments, Inc. (February 19, 2008). What’s the Difference Between “Explosion Proof” & “Intrinsically Safe”. Retrieved from http://www.rkiinstruments.com/pdf/FAQ_Explosion_Proof.pdf

Posted in EducationalComments Off on What is the Difference Between Explosion Proof and Intrinsically Safe Gas Detectors?


  • I posted a new photo to Facebook ,
  • CETCI Launches the FCS Flexible Control System, a High Performance Gas Detection Controller with Logic Control... ,
  • We are going to the AHR Expo in Vegas. Are you? If so, drop by our booth to say Hi! Check us out on Map Your Show... ,
  • I posted a new photo to Facebook ,
  • Tutorial – How to Calibrate the DST-ECO: via @YouTube,
  • Last day of the AHR Expo in Mexico. Word is, it's been a great show!,
  • We make gas detectors for monitoring toxic, combustible and refrigerant gases for a wide range of applications.... ,
  • BTL Listing granted for CETCI BACnet® Module... ,

Gas Detectors

CETCI gas detectors are used to detect many different gases. Some of the most common are Carbon Monoxide, Carbon Dioxide, Nitrogen Dioxide, Nitric Oxide, Ammonia, Chlorine, Ozone, Combustible Gases like Methane and Propane, Oxygen, Refrigerants and more.

IAQ Monitors

The YES Series of IAQ Monitors are essential for those responsible for conducting Indoor Air Quality (IAQ) Investigations. These instruments are specifically designed to measure and record the quality of indoor air in offices, buildings, homes, schools, parking garages, ice rinks, etc.