# CET — Critical Environment Technologies > Environmental monitoring hardware and software for HVAC, refrigerant leak detection, indoor air quality, and industrial gas safety. CET designs and manufactures gas detectors, controllers, and monitoring systems used in mechanical rooms, parking garages, cold storage, laboratories, and industrial facilities worldwide. This file lists the primary public content on the site for AI assistants. ## Products - [Cal Clip Calibration Adapter](https://www.critical-environment.com/products/accessories/cal-clip-calibration-adapter): Clips around the circular, black splash guard that is factory installed at the time of order on any CET black enclosure gas detectors or se… - [Calibration Gases](https://www.critical-environment.com/products/accessories/calibration-gases): Cylinders of zero air and span gas for calibration Request a quote from CET. - [Calibration Kits](https://www.critical-environment.com/products/accessories/calibration-kits): Complete calibration kits for CET gas detectors. Includes regulators, tubing, and adapters. Available for single-gas and multi-gas systems. - [Certificate of Sensor Calibration](https://www.critical-environment.com/products/accessories/certificate-of-sensor-calibration): Provides detailed sensor calibration information. A Certificate of Sensor Calibration is available for customers who require detailed calib… - [cGas Detector Ammonia Vent Line Transmitter](https://www.critical-environment.com/products/specialty/cgas-detector-ammonia-vent-line-transmitter): For continuous monitoring of Ammonia levels in the vent line of refrigeration systems. Mount indoors on the ammonia vent relief stack in re… - [cGas Detector Analog Transmitter](https://www.critical-environment.com/products/gas-detectors/cgas-detector-analog-transmitter): Single channel, analog gas detector with Plug & Play Smart Sensor Technology. Request a quote from CET. - [cGas Detector Digital Transmitter](https://www.critical-environment.com/products/gas-detectors/cgas-detector-digital): One or two channel Modbus® or BACnet® gas detector with flexible customization options and Plug & Play Smart Sensor Technology. Request a q… - [cGas Detector for Indoor Public Spaces](https://www.critical-environment.com/products/gas-detectors/cgas-detector-indoor-public-spaces): Single channel gas detector with an aesthetically pleasing design to reduce noticeability when used in publicly occupied spaces such as hot… - [cGas Detector IR Refrigerant Transmitter](https://www.critical-environment.com/products/gas-detectors/cgas-detector-ir-refrigerant-transmitter): Non-dispersive infrared refrigerant gas detector with accurate, low level leak detection, available with analog output or BACnet® or Modbus… - [cGas Detector VRF IR Refrigerant Transmitter](https://www.critical-environment.com/products/gas-detectors/cgas-detector-vrf-ir-refrigerant-transmitter): NDIR refrigerant detector for VRF systems. Detect R-32, R-454B, and other A2L refrigerants. Aesthetic design for occupied spaces. BACnet/Mo… - [cGas-SC Self-Contained Controller](https://www.critical-environment.com/products/controllers/cgas-sc): A self contained controller with up to 3 gas channels, Plug & Play Smart Sensor Technology and configurable logic control and priority sett… - [cGas-SD Sample Draw System](https://www.critical-environment.com/products/specialty/cgas-sd-sample-draw-system): A Self-contained, single sensor sample draw gas detection system that draws sample air from locations where it is difficult to install a ga… - [CXT2 Explosion Proof Transmitter](https://www.critical-environment.com/products/gas-detectors/cxt2): Reliable, accurate monitoring of toxic or combustible gases in potentially explosive and harsh environments, including hazardous-rated area… - [Duct Sampling Kit](https://www.critical-environment.com/products/accessories/duct-sampling-kit): A special probe assembly that attaches to a gas detector and is mounted on the return air duct of a ventilation system to measure the conce… - [ESH-A Remote Sensor](https://www.critical-environment.com/products/gas-detectors/esh-a-remote-sensor): Single analog remote sensor for flexible location monitoring. Request a quote from CET. - [FCS Multi Channel System Controllers](https://www.critical-environment.com/products/controllers/fcs-multi-channel-system-controllers): High performance controller with logic and priority settings for monitoring toxic, combustible and refrigerant gases with versatile control… - [LNK-AI Analog Input Peripheral Device](https://www.critical-environment.com/products/remote-devices/lnk-ai-analog-input-peripheral-device): Adds 4 additional analog inputs to a gas detection system. The LNK-AI Analog Input peripheral device adds four channels of 4 - 20 mA or 0 -… - [LNK-AO Analog Output Peripheral Device](https://www.critical-environment.com/products/remote-devices/lnk-ao-analog-output-peripheral-device): Adds 4 additional analog outputs to a gas detection system. Adds four channels of 4 - 20 mA analog output to a Modbus® RS-485 network confi… - [LNK-XT Network Extender Peripheral Device](https://www.critical-environment.com/products/remote-devices/lnk-xt-network-extender-peripheral-device): Works as signal booster and allows a longer distance between devices. Ideal for large applications to create an efficient distribution netw… - [LPT Low Power Transmitter](https://www.critical-environment.com/products/gas-detectors/lpt): Single channel, analog gas detector for enclosed parking facilities, recreational facilities, oxygen depletion applications. Request a quot… - [Magnetic Wand](https://www.critical-environment.com/products/accessories/magnetic-wand): Use for initiating calibration and accessing menu options and programming functions of several CETCI gas detectors without having to open t… - [Manual Shutoff Switch (Option -SW)](https://www.critical-environment.com/products/accessories/manual-shutoff-switch-option-sw): An emergency stop, push button switch that allows a person to manually shutdown equipment in the event of an emergency. Ideal for refrigera… - [Metal Protective Guards](https://www.critical-environment.com/products/accessories/metal-protective-guards): A heavy duty metal guard that is installed over the gas detector or controller. Helps protect the gas detection equipment against impact, a… - [PRU-24-A Sample Draw Pump Unit](https://www.critical-environment.com/products/specialty/pru-24-a-sample-draw-pump-unit): Connects to a gas detector and draws samples of air into the gas detector from hard to access locations such as shafts, tall ceilings, well… - [RDM Remote Display](https://www.critical-environment.com/products/remote-devices/rdm-remote-display): Provides convenient viewing of gas level readings from a secondary location. Displays gas level readings, channel status and faults receive… - [Remote Industrial Horn](https://www.critical-environment.com/products/remote-devices/remote-industrial-horn): Surface mount industrial horn with mounting bracket, available for indoor or outdoor use. A low-current, high decibel, surface mount, vibra… - [Replacement Sensors for cGas Product Line](https://www.critical-environment.com/products/gas-detectors/replacement-sensors-for-cgas-detectors): Replacement Plug & Play Smart Sensor Boards for CGAS-A, CGAS-D, CGAS-AP, CGAS-DP, CGAS-SC and CGAS-SD models. Gas sensors have a lifespan w… - [RLY-4 and RLY-8 Remote Relays](https://www.critical-environment.com/products/remote-devices/rly-4-and-rly-8-remote-relays): Provides an additional 4 or 8 physical relays to a fixed gas detection system plus an additional 2 or 4 horn/strobe drives. Request a quote… - [RPS-24VDC Remote Power Supply](https://www.critical-environment.com/products/remote-devices/rps-24vdc-remote-power-supply): Provides additional power to large networks. Converts 90 - 240 VAC power to 24 VDC power, providing a renewed amount of power to compensate… - [RSA-24V Remote LED Strobe Light](https://www.critical-environment.com/products/remote-devices/rsa-24v-remote-led-strobe-light): Bright visual alarm with multiple user selectable flash patterns. A remote LED strobe light with multiple user selectable flash patterns, c… - [RSH-24V Remote Strobe & Horn](https://www.critical-environment.com/products/remote-devices/rsh-24v-remote-strobe-horn): Two alarm features in one safety device, mounting fixture not included. Available in 3 different lens colours, combines a visual and an aud… - [RSL Remote Stack Light](https://www.critical-environment.com/products/remote-devices/rsl-remote-stack-light): Tower light with modular LED colors with steady or flashing light settings and two different sound types. A compact, pole mounted signal li… - [RSW Remote Switch](https://www.critical-environment.com/products/remote-devices/rsw-remote-switch): Enables manual operation of equipment with emergency shutdown, activation or reset as needed. Easy push button action, satisfies compliance… - [Splash Guard (Option -S)](https://www.critical-environment.com/products/accessories/splash-guard-option-s): Protects sensor from water, dust and dirt; factory installed over the sensor vent, IP54 rating. Recommended for gas detectors installed in… - [Splash Guard for Sticky Gases (Option -SN)](https://www.critical-environment.com/products/accessories/splash-guard-for-sticky-gases-option-sn): Protects sticky gas sensor from water, dust and dirt. Recommended for gas detectors with sticky gas sensors installed in wash down or wet e… - [TMS-R Remote Strobe](https://www.critical-environment.com/products/remote-devices/tms-r-remote-strobe): A high powered, red LED flashing beacon that offers excellent flash intensity, durable vibration resistant construction and a long life. 4… - [Top Mounted Strobe (Option -L)](https://www.critical-environment.com/products/accessories/top-mounted-strobe-option-l): A high powered, red LED flashing beacon that is factory installed at time of order and offers excellent flash intensity, durable vibration… ## Applications - [Battery Charging](https://www.critical-environment.com/applications/battery-charging): Hydrogen gas detection for battery charging rooms and forklift charging stations. Prevent explosions from lead-acid and lithium-ion battery… - [Boiler Rooms](https://www.critical-environment.com/applications/boiler-rooms): Gas detection for boiler rooms and mechanical spaces: natural gas leaks, CO from incomplete combustion, and refrigerant monitoring. IMC com… - [Breweries](https://www.critical-environment.com/applications/breweries): Brewery CO2 and oxygen monitoring for fermentation tanks, cellars, and walk-in coolers. Protect brewery workers from asphyxiation hazards. - [Car Dealerships](https://www.critical-environment.com/applications/car-dealerships): Gas detection for car dealerships: CO and NO2 monitoring for indoor showrooms, service departments, and vehicle storage. Protect customers… - [Chiller Rooms](https://www.critical-environment.com/applications/chiller-rooms): Refrigerant leak detection for chiller rooms and mechanical plants. ASHRAE 15 compliant monitoring for R-410A, R-32, ammonia, and A2L refri… - [CO₂ Enrichment](https://www.critical-environment.com/applications/co2-enrichment): CO2 enrichment monitors for greenhouses and indoor farms. Detect dangerous CO2 dosing levels and oxygen depletion. ASHRAE-compliant safety. - [Cold Storage](https://www.critical-environment.com/applications/cold-storage): Gas detection for cold storage facilities, walk-in freezers, and food distribution centers. Monitor ammonia, CO2 refrigerants, and oxygen d… - [Commercial Kitchens](https://www.critical-environment.com/applications/commercial-kitchens): Gas detection for commercial kitchens: natural gas and propane leak monitoring, CO from ranges and ovens. Protect restaurant staff and patr… - [Data Centers](https://www.critical-environment.com/applications/data-centers): Data center gas detection for UPS battery rooms (hydrogen) and cooling systems (refrigerants). Protect critical infrastructure with continu… - [Distilleries](https://www.critical-environment.com/applications/distilleries): Explosion-proof ethanol gas detectors for distilleries. Monitor fermentation CO2, ethanol vapors, and combustible gases. Protect workers an… - [Emergency Vehicle Bays](https://www.critical-environment.com/applications/emergency-vehicle-bays): Gas detection for fire stations, ambulance bays, and police garages: CO and diesel exhaust monitoring. Protect first responders from exhaus… - [EV Charging](https://www.critical-environment.com/applications/ev-charging): Gas detection for EV charging facilities: hydrogen off-gassing, thermal runaway, and battery fire prevention. Protect parking structures an… - [Fleet & Bus Depots](https://www.critical-environment.com/applications/fleet-bus-depots): Gas detection for bus depots and fleet maintenance facilities: CO, NO2, and diesel exhaust monitoring. Transit authority and delivery fleet… - [Greenhouses](https://www.critical-environment.com/applications/greenhouses): Gas detection for commercial greenhouses: CO2 enrichment safety, propane/natural gas heater monitoring, and worker protection in controlled… - [Grow Rooms](https://www.critical-environment.com/applications/grow-rooms): Multi-gas detection for cannabis grow rooms and vertical farms. CO2, propane, natural gas, and oxygen depletion monitoring for licensed cul… - [Hospitals](https://www.critical-environment.com/applications/hospitals): Gas detection for hospitals and medical facilities: oxygen depletion, anesthetic gases, and medical gas storage areas. Protect patients and… - [Hotels](https://www.critical-environment.com/applications/hotels): Refrigerant leak detection for hotels and hospitality: VRF system monitoring in guest rooms and common areas. Aesthetic sensors for occupie… - [Ice Arenas](https://www.critical-environment.com/applications/ice-arenas): Multi-gas detection for ice rinks: ammonia refrigerant leaks, CO from ice resurfacers, and NO2 from propane Zambonis. Protect athletes and… - [Indoor Air Quality](https://www.critical-environment.com/applications/indoor-air-quality): Commercial IAQ monitors for offices, schools, and public spaces: CO2 for ventilation, CO for combustion safety, TVOC for air quality. BACne… - [Laboratories](https://www.critical-environment.com/applications/laboratories): Gas detection for research and clinical labs: oxygen depletion, cryogenic gases, and chemical hazards. Protect laboratory personnel from to… - [MRI Rooms](https://www.critical-environment.com/applications/mri-rooms): MRI suite gas detection for helium quench events and oxygen depletion. Protect patients and technicians from cryogenic hazards. Magnet room… - [Parking Garages](https://www.critical-environment.com/applications/parking-garages): CO and NO2 gas detection for enclosed parking garages. Meet IMC ventilation codes with BACnet-integrated sensors. Reduce energy costs up to… - [Pools & Aquatics](https://www.critical-environment.com/applications/pools): Gas detection for indoor pools and natatoriums: chlorine, chloramine, and CO2 monitoring. Protect swimmers and staff from chemical exposure. - [Schools](https://www.critical-environment.com/applications/schools): Gas detection for schools: CO2 for classroom IAQ, CO/natural gas for boiler rooms, and refrigerant monitoring. Protect students and staff. - [Transit Facilities](https://www.critical-environment.com/applications/transit-facilities): Gas detection for subway stations, bus terminals, and transit hubs: CO, NO2, CO2 and particulate monitoring. Protect passengers and transit… - [Vehicle Service Bays](https://www.critical-environment.com/applications/vehicle-service-bays): Gas detection for automotive service bays, repair shops, and oil change facilities. CO and NO2 monitoring with demand-controlled exhaust ve… - [Warehouses](https://www.critical-environment.com/applications/warehouses): Gas detection for warehouses and distribution centers: CO and NO2 from forklifts, truck loading, and vehicle exhaust. Protect workers in en… - [Waste & Recycling](https://www.critical-environment.com/applications/waste-recycling): Gas detection for material recovery facilities: methane, H2S, and combustible gases from decomposing waste. Explosion-proof options for haz… - [Wastewater Treatment](https://www.critical-environment.com/applications/wastewater-treatment): Gas detection for wastewater facilities: H2S, methane, and oxygen monitoring for pump stations, digesters, and headworks. Explosion-proof o… - [Welding Shops](https://www.critical-environment.com/applications/welding-shops): Gas detection for welding and fabrication shops: shielding gas oxygen depletion, combustible gas leaks, and fume monitoring. Protect metalw… - [Wineries](https://www.critical-environment.com/applications/wineries): Winery CO2 and oxygen detection for fermentation rooms, barrel cellars, and tank farms. Protect workers from asphyxiation during crush seas… ## Gases - [Ammonia](https://www.critical-environment.com/gases/ammonia): Commercial ammonia (NH3) leak detectors for refrigeration and industrial facilities. Meet IIAR-2 standards. OSHA 25 ppm TWA compliant senso… - [Carbon Dioxide](https://www.critical-environment.com/gases/carbon-dioxide): Commercial CO2 detectors with NDIR sensors for breweries, greenhouses, and IAQ. BACnet/Modbus integration. Monitor 0-5000 ppm and 0-5% rang… - [Carbon Monoxide](https://www.critical-environment.com/gases/carbon-monoxide): Commercial carbon monoxide detectors with BACnet/Modbus output. Building automation integration for parking garages, boiler rooms, and load… - [Chlorine](https://www.critical-environment.com/gases/chlorine): Detect chlorine gas leaks in pools, water treatment, and industrial facilities. Cl2 sensors with 0-10ppm range. OSHA compliant with BACnet… - [Ethanol](https://www.critical-environment.com/gases/ethanol): Commercial ethanol vapor detectors for distilleries, breweries, fuel storage. Explosion-proof C2H5OH or C2H6O sensors with BACnet/Modbus fo… - [Formaldehyde](https://www.critical-environment.com/gases/formaldehyde): Commercial CH2O detectors for laboratories and mortuaries and many industrial process. Furniture off-gassing. OSHA/ASHRAE compliant. - [HFO-1233zd](https://www.critical-environment.com/gases/hfo-1233zd): Detect HFO-1233zd refrigerant leaks in low-pressure HFO chiller rooms. CET commercial sensors meet ASHRAE 15 and OSHA standards. - [Hydrogen](https://www.critical-environment.com/gases/hydrogen): Commercial hydrogen (H2) gas detectors for battery rooms, EV charging, and fuel cell facilities. Catalytic bead and electrochemical sensors. - [Hydrogen Sulfide](https://www.critical-environment.com/gases/hydrogen-sulfide): Commercial H2S detectors for wastewater, oil & gas, and industrial facilities. Hydrogen sulfide sensors with 0-100ppm range. OSHA 10ppm cei… - [Methane](https://www.critical-environment.com/gases/methane): Commercial methane (CH4) detectors for natural gas, biogas, and landfill applications. Catalytic and infrared LEL sensors. - [Natural Gas](https://www.critical-environment.com/gases/natural-gas): Commercial natural gas leak detectors for kitchens, boiler rooms, and mechanical spaces. Methane sensors with BACnet integration. NFPA 54 c… - [Nitric Oxide](https://www.critical-environment.com/gases/nitric-oxide): Nitric oxide gas detectors for boiler rooms, welding, combustion processes. NO sensors detect 0-250ppm. Often paired with NO2 monitoring. O… - [Nitrogen Dioxide](https://www.critical-environment.com/gases/nitrogen-dioxide): Commercial NO2 detectors for parking garages, loading docks, and diesel equipment areas. Electrochemical sensors. OSHA 5 ppm ceiling limit… - [Oxygen](https://www.critical-environment.com/gases/oxygen): Oxygen monitors for confined spaces, MRI rooms, and cryogenic facilities. Detect O2 depletion (<19.5%) and enrichment (>23.5%). OSHA compli… - [Ozone](https://www.critical-environment.com/gases/ozone): Commercial ozone monitors for water treatment, food processing, and HVAC applications. O3 sensors measure 0-1ppm with OSHA compliance. - [Propane](https://www.critical-environment.com/gases/propane): Commercial propane (C3H8) gas detectors for LPG leak monitoring. Catalytic and infrared sensors with BACnet output. Explosion-proof options… - [R-1234yf](https://www.critical-environment.com/gases/r-1234yf): Detect R-1234yf refrigerant leaks in automotive AC systems. Low-GWP A2L mildly flammable HFO refrigerant monitoring per ASHRAE 15. - [R-1234ze](https://www.critical-environment.com/gases/r-1234ze): Detect R-1234ze refrigerant leaks in chillers and foam-blowing systems. Low-GWP A2L HFO refrigerant monitoring per ASHRAE 15. - [R-134a](https://www.critical-environment.com/gases/r-134a): Detect R-134a (C₂H₂F₄) with CET commercial detectors. Common hydrofluorocarbon refrigerant OSHA/ASHRAE compliant. - [R-143a](https://www.critical-environment.com/gases/r-143a): Detect R-143a (C₂H₃F₃) with CET commercial detectors. HFC blend component refrigerant OSHA/ASHRAE compliant. - [R-22](https://www.critical-environment.com/gases/r-22): Detect R-22 (CHClF₂) with CET commercial detectors. HCFC refrigerant being phased out under Montreal Protocol OSHA/ASHRAE compliant. - [R-227ea](https://www.critical-environment.com/gases/r-227ea): Detect R-227ea (C₃HF₇) with CET commercial detectors. HFC used in fire suppression and chillers OSHA/ASHRAE compliant. - [R-32](https://www.critical-environment.com/gases/r-32): Detect R-32 (CH2F2) refrigerant leaks in mini-split and VRF systems. A2L mildly flammable monitoring per ASHRAE 15. Low-GWP R-410A alternat… - [R-404A](https://www.critical-environment.com/gases/r-404a): Detect R-404A (R125/R143a/R134a) with CET commercial detectors. Commercial refrigeration HFC blend OSHA/ASHRAE compliant. - [R-407A](https://www.critical-environment.com/gases/r-407a): Detect R-407A (R32/R125/R134a) with CET commercial detectors. R-22 replacement for AC systems OSHA/ASHRAE compliant. - [R-407C](https://www.critical-environment.com/gases/r-407c): Detect R-407C (R32/R125/R134a) with CET commercial detectors. Common R-22 retrofit refrigerant OSHA/ASHRAE compliant. - [R-407F](https://www.critical-environment.com/gases/r-407f): Detect R-407F (R32/R125/R134a) with CET commercial detectors. Low/medium temperature refrigerant OSHA/ASHRAE compliant. - [R-410A](https://www.critical-environment.com/gases/r-410a): Detect R-410A refrigerant leaks in HVAC systems. CET commercial sensors with BACnet/Modbus integration. ASHRAE 15 and OSHA compliant. - [R-417A](https://www.critical-environment.com/gases/r-417a): Detect R-417A (R125/R134a/Butane) with CET commercial detectors. Drop-in R-22 replacement blend OSHA/ASHRAE compliant. - [R-422D](https://www.critical-environment.com/gases/r-422d): Detect R-422D (R125/R134a/Isobutane) with CET commercial detectors. R-22 retrofit refrigerant blend OSHA/ASHRAE compliant. - [R-438A](https://www.critical-environment.com/gases/r-438a): Detect R-438A (R32/R125/R134a/R600/R601a) with CET commercial detectors. ISCEON MO99 R-22 replacement OSHA/ASHRAE compliant. - [R-448A](https://www.critical-environment.com/gases/r-448a): Detect R-448A (R32/R125/R134a/R1234yf/R1234ze) with CET commercial detectors. Solstice N40 supermarket refrigerant OSHA/ASHRAE compliant. - [R-449A](https://www.critical-environment.com/gases/r-449a): Detect R-449A (R32/R125/R134a/R1234yf) with CET commercial detectors. Opteon XP40 commercial refrigerant OSHA/ASHRAE compliant. - [R-450A](https://www.critical-environment.com/gases/r-450a): Detect R-450A (R134a/R1234ze) with CET commercial detectors. Low-GWP chiller refrigerant blend OSHA/ASHRAE compliant. - [R-452A](https://www.critical-environment.com/gases/r-452a): Detect R-452A (R32/R125/R1234yf) with CET commercial detectors. Transport refrigeration blend OSHA/ASHRAE compliant. - [R-454B](https://www.critical-environment.com/gases/r-454b): Detect R-454B refrigerant leaks. A2L mildly flammable R-410A replacement (Puron Advance) monitoring per ASHRAE 15 and UL 60335-2-40. - [R-507](https://www.critical-environment.com/gases/r-507): Detect R-507 (R125/R143a) with CET commercial detectors. Industrial refrigeration HFC blend OSHA/ASHRAE compliant. - [R-513A](https://www.critical-environment.com/gases/r-513a): Detect R-513A (R134a/R1234yf) with CET commercial detectors. Opteon XP10 chiller refrigerant OSHA/ASHRAE compliant. - [R-514A](https://www.critical-environment.com/gases/r-514a): Detect R-514A (HFO-1336mzz and t-DCE) with CET commercial detectors. B2L low-pressure chiller refrigerant OSHA/ASHRAE compliant. - [R-515B](https://www.critical-environment.com/gases/r-515b): Detect R-515B (R-1234ze(E) and R-227ea) with CET commercial detectors. A1 classification and very low GWP make it a popular alternative to… - [R-744](https://www.critical-environment.com/gases/r-744): Detect R-744 CO2 refrigerant leaks in transcritical commercial refrigeration systems. CET sensors meet ASHRAE 15 and OSHA standards. - [R454C](https://www.critical-environment.com/gases/r454c) - [Sulfur Dioxide](https://www.critical-environment.com/gases/sulfur-dioxide): Commercial Sulfur Dioxide (SO₂) detector for chemical plants. Colorless gas with a sharp, pungent smell. OSHA/ASHRAE compliant. ## Resources - [Specifying a Gas Sensor: A Technical Guide for Engineers and Dealers](https://www.critical-environment.com/company/news/specifying-a-gas-sensor-a-technical-guide-for-engineers-and-dealers): A technical gas sensor guide for specifying engineers and dealers: sensor technology selection, code references, signal outputs, and spec l… - [CET Adds NDIR Combustible Gas Sensor Options to cGas Detector Family](https://www.critical-environment.com/company/news/cet-adds-ndir-combustible-gas-sensor-options-to-cgas-detector-family): CET has expanded its cGas gas detection platform with advanced non-dispersive infrared (NDIR) sensors for methane and propane detection, pr… - [Combustible Gas Detection: NDIR vs Catalytic Technology](https://www.critical-environment.com/company/news/combustible-gas-detection-ndir-vs-catalytic-technology): The differences between NDIR and catalytic gas sensors, from poisoning resistance and maintenance costs to hydrogen detection and lifecycle… - [Analog vs. Digital Connections in Gas Detection Integration with Building Automation Systems](https://www.critical-environment.com/company/news/analog-vs-digital-connections-in-gas-detection-integration-with-building-automation-systems): Effective integration between gas detection systems, BAS, alarms and ventilation controls depends on how devices communicate. The chosen co… - [What Is the Respiratory Zone? A Guide to Gas Detector Placement](https://www.critical-environment.com/company/news/what-is-the-respiratory-zone-a-guide-to-gas-detector-placement): Learn what the respiratory zone is, why it matters for gas detection, and how proper sensor placement protects people in parking garages, w… - [Why Integrate Gas Detection into BMS, BAS or PLC Systems?](https://www.critical-environment.com/company/news/why-integrate-gas-detection-into-bms-or-plc-systems): Integration with BMS, BAS or other type of control system enables automated ventilation and safety controls and ensures responsive facility… - [Why Gas Detection Matters in Places Meant for Play](https://www.critical-environment.com/company/news/why-gas-detection-matters-in-places-meant-for-play): Gas detection in arenas, rinks, and recreational facilities: protecting kids, families, and staff from CO and refrigerant exposure. - [Hidden Air Quality Risks in Transit Environments](https://www.critical-environment.com/company/news/hidden-air-quality-risks-in-transit-environments): Gas detection for subway stations, bus terminals, transit hubs: CO and NO2 monitoring. Air quality for passengers and transit workers. - [When Gas Detection Drives Ventilation: Smarter, Safer, More Efficient Buildings](https://www.critical-environment.com/company/news/when-gas-detection-drives-ventilation-smarter-safer-more-efficient-buildings): How CET gas detectors integrate with ventilation fans for demand-controlled ventilation. Save energy while maintaining safety. 30+ years of… - [Diffusion and Gas Detection](https://www.critical-environment.com/company/news/diffusion-and-gas-detection): Diffusion impacts gas detection including response time, calibration accuracy, and sensor performance. Factors like humidity, temperature a… - [Signs and Symptoms of Propane Gas Exposure](https://www.critical-environment.com/company/news/signs-symptoms-propane-gas-exposure): Recognize propane gas exposure symptoms: headaches, dizziness, nausea, and difficulty breathing. Learn emergency response and detection sol… - [Understanding VRF Systems and Refrigerant Safety](https://www.critical-environment.com/company/news/understanding-vrf-systems-refrigerant-safety): Complete guide to VRF system safety and A2L refrigerant monitoring. Learn ASHRAE 15 requirements for variable refrigerant flow leak detecti… - [New Year, New Safety: Why Now Is the Perfect Time to Review Your Gas Detector Maintenance](https://www.critical-environment.com/company/news/new-year-new-safety-why-now-is-the-perfect-time-to-review-your-gas-detector-maintenance): A fresh year calls for fresh safety checks - make gas detector maintenance your first resolution. Read more from CET. - [Next Generation Calibration Cap](https://www.critical-environment.com/company/news/cal-cap-adapter): CET introduces the next generation Cal Cap calibration adapter, making gas detector field calibration faster and hands-free for facility ma… - [Why Infrared Refrigerant Gas Sensors Outperform Solid-State Sensors](https://www.critical-environment.com/company/news/why-infrared-refrigerant-gas-sensors-outperform-solid-state-sensors): Why NDIR infrared refrigerant sensors outperform solid-state: longer life, fewer false alarms, and better accuracy. Compare sensor technolo… - [cGas Detector VRF IR Advanced Safety for Modern HVAC Systems](https://www.critical-environment.com/company/news/cgas-detector-vrf-advanced-safety-for-modern-hvac-systems): Provides continuous monitoring for acute refrigerant leaks in modern energy-efficient buildings utilizing Variable Refrigerant Flow (VRF) H… - [Monitoring the Invisible Gas in Data Centers](https://www.critical-environment.com/company/news/monitoring-the-invisible-gas-in-data-centers): One key safety issue that data centers face is the buildup of hydrogen gas in the battery rooms. Hydrogen gas detectors are essential to en… - [Trusted Integration: CET Gas Detection + Ventilation Fans for Safer, Smarter Buildings](https://www.critical-environment.com/company/news/trusted-integration-cet-gas-detection-ventilation-fans-for-safer-smarter-buildings): With 30+ years of experience, we provide reliable integration. CET gas detection systems seamlessly work with diverse ventilation fans, del… - [Best Practices for Gas Detection and Safety Compliance in Chiller Rooms](https://www.critical-environment.com/company/news/best-practices-for-gas-detection-and-safety-compliance-in-chiller-rooms): A gas detection system in a chiller room is not just a precaution"”it's a critical safety measure. Read more from CET. - [Manufacturer Recommendations for Testing and Calibrating CET Gas Detection Systems](https://www.critical-environment.com/company/news/manufacturer-recommendations-for-testing-and-calibrating-cet-gas-detection-systems): How often should gas detectors be calibrated? Learn manufacturer recommendations for bump testing and calibration frequency to maintain acc… - [A Guide for Maintaining Gas Detectors](https://www.critical-environment.com/company/news/a-guide-for-maintaining-gas-detectors): Regular maintenance and inspection of the gas detection system helps identify and correct problems before they escalate and lead to false r… - [Why the Sensor Coverage Range is Larger in Parking Garages](https://www.critical-environment.com/company/news/why-the-coverage-range-is-larger-in-parking-garages): The sensor coverage range for CO and NO2 gas detectors in parking garages is larger than many other applications. Find out why. Read more f… - [The Advantages of Infrared Refrigerant Gas Sensors over Solid State Sensors](https://www.critical-environment.com/company/news/the-advantages-of-infrared-refrigerant-gas-sensors): Infrared refrigerant gas sensors offer a powerful combination of accuracy, reliability, and low maintenance, making them an excellent choic… - [cGas-SD: A Smarter, Simpler, and More Capable Sample Draw System](https://www.critical-environment.com/company/news/cgas-sd-a-smarter-simpler-and-more-capable-sample-draw-system): Designed to replace the legacy DCC-SD and DCC-MRI systems, the cGas-SD brings a new level of performance, usability, and flexibility to gas… - [Why a Multi-Point Sample Draw System May Not Be the Right Choice](https://www.critical-environment.com/company/news/why-a-multi-point-sample-draw-system-may-not-be-recommended): While multi-point sample draw systems can seem efficient, they come with significant risks and drawbacks that may outweigh their benefits i… - [The Dual Nature of Oxygen](https://www.critical-environment.com/company/news/the-dual-nature-of-oxygen): Oxygen is essential for life, yet it can also pose significant risks. Ensuring that oxygen levels are properly monitored and maintained is… - [Introducing the cGas-SD: A Smart Solution for Hard-to-Reach Gas Monitoring Challenges](https://www.critical-environment.com/company/news/introducing-the-cgas-sd-a-smart-solution-for-hard-to-reach-gas-monitoring-challenges): The cGas-SD Sample Draw System elevates your safety standards with precision monitoring. Read more from CET. - [Gas Detectors: Vital Safety Systems for Preventing Injuries, Illness, and Death](https://www.critical-environment.com/company/news/gas-detectors-vital-safety-systems-for-preventing-injuries-illness-and-death): Gas detectors are vital safety devices designed to monitor and measure potentially lethal gases in various environments, safeguarding lives… - [Height Matters: Gas Detector Mounting Height](https://www.critical-environment.com/company/news/height-matters-gas-detector-mounting-height): The height at which to mount a fixed gas detector depends on the density of the target gas relative to air and can also depend on the on th… - [Ensuring Safety and Efficiency in Greenhouse Facilities](https://www.critical-environment.com/company/news/ensuring-safety-and-efficiency-in-greenhouse-facilities): The integration of gas detection systems in greenhouse production and oil extraction facilities is essential for maintaining safety and eff… - [Celebrating 30 Years of Innovation: The Evolution of Gas Detection at Critical Environment Technologies](https://www.critical-environment.com/company/news/celebrating-30-years-of-innovation-the-evolution-of-gas-detection-at-critical-environment-technologies): At CET, we've been at the forefront of the gas detection evolution. Our journey over the past 30 years has been marked by continuous improv… - [FAQ About Ammonia Gas Detection Systems](https://www.critical-environment.com/company/news/faq-about-ammonia-gas-detection-systems): Ammonia is a corrosive, toxic gas or liquid used in manufacturing and refrigeration. Exposure to high levels of ammonia can be fatal. Learn… - [Understanding A2L Refrigerants: Safety, Standards and Detection](https://www.critical-environment.com/company/news/understanding-a2l-refrigerants-safety-standards-and-detection): A2L mildly flammable refrigerant monitoring per ASHRAE 15-2024 Code Requirements for Gas Detection Systems with EOL and LFL considerations. - [Making the Conversion Easier: Converting ppm to %vol](https://www.critical-environment.com/company/news/making-the-conversion-easier-converting-ppm-to-vol): With practice and the right tools, this conversion becomes simple—an essential part of accurate, compliant gas detection. Read more from CE… - [The Importance of Low Temperature Options in Gas Detectors](https://www.critical-environment.com/company/news/the-importance-of-low-temperature-options-in-gas-detectors): By incorporating a low temperature package, gas detectors can provide reliable performance and safety across a wider range of environments.… - [Ensuring Safety with Gas Detectors: Best Practices](https://www.critical-environment.com/company/news/ensuring-safety-with-gas-detectors-best-practices): Ensuring safety with gas detectors involves proper usage, calibration, and maintenance to effectively monitor hazardous gases and protect l… - [How to Convert ppm to %vol](https://www.critical-environment.com/company/news/how-to-convert-ppm-to-vol): How to convert ppm to %vol for gas concentrations. Simple formula, worked examples, and a reference table for common gases used in detectio… - [Bedbug Problem? Carbon Dioxide (CO₂) Solution!](https://www.critical-environment.com/company/news/bedbug-problem-carbon-dioxide-co2-solution): Precautions when using CO2 and cryonite treatments for bedbug extermination - [Fixed vs Portable Gas Detection Equipment](https://www.critical-environment.com/company/news/fixed-vs-portable-gas-detection-equipment): When choosing between fixed and portable gas detectors there are many factors to consider to ensure the proper monitoring measures are bein… - [Navigating the Hazardous Gases in Breweries](https://www.critical-environment.com/company/news/navigating-the-hazardous-gases-in-breweries): When considering the hazardous gases in a brewery, CO2 is likely the first to come to mind. While it plays a crucial role in brewing, other… - [Miswire could cause a circuit board fire!](https://www.critical-environment.com/company/news/miswire-could-cause-a-circuit-board-fire): Gas detectors rely on accurate signals to detect gas concentrations. Proper wiring prevents interference, signal loss, or noise that could… - [The Oxides of Nitrogen - NO and NO₂](https://www.critical-environment.com/company/news/the-oxides-of-nitrogen-no-and-no2): Both NO and NO2 are produced during the combustion process and are emitted into the air through the exhaust of gasoline run vehicles. What… - [Even when you are inside a building, you may not be safe!](https://www.critical-environment.com/company/news/even-when-you-are-inside-a-building-you-may-not-be-safe): Wildfire smoke contains fine particles that can irritate the respiratory system, damage lung tissue, and increase long‑term health risks. E… - [The Wonders of Ammonia & Chlorine](https://www.critical-environment.com/company/news/the-wonders-of-ammonia-chlorine-2656): They are all around you, be aware of them and stay safe. Read more from CET. - [Calibration Could Save Your Life](https://www.critical-environment.com/company/news/calibration-could-save-your-life-2671): Many gases—some detectable by humans, others not—can leak into the spaces where we work and play, becoming dangerous when they exceed safe… - [Solid State Gas Sensors & Factors Affecting Life Expectancy](https://www.critical-environment.com/company/news/solid-state-gas-sensors-factors-affecting-life-expectancy): Solid‑state sensors are versatile and can detect many gases, but they require clean, stable environments with minimal temperature and humid… - [Non-dispersive Infrared Gas Sensors & Factors Affecting Life Expectancy](https://www.critical-environment.com/company/news/non-dispersive-infrared-gas-sensors-factors-affecting-life-expectancy): Non-dispersive infrared sensors accurately detect CO2 and refrigerant gases without cross interference from toxic or combustible gases beca… - [At What Height Should Sensors be Mounted?](https://www.critical-environment.com/company/news/at-what-height-should-sensors-be-mounted): Sensor mounting height by gas: heavier-than-air gases low, lighter-than-air gases high. Practical guide for CO, CO2, refrigerants, propane,… - [Catalytic Gas Sensors & Factors Affecting Life Expectancy](https://www.critical-environment.com/company/news/catalytic-gas-sensors-factors-affecting-life-expectancy): Catalytic sensors are used for detecting combustible, or flammable gases, such as methane, propane and hydrogen. They are a safe and reliab… - [Electrochemical Gas Sensors & Factors Affecting Life Expectancy](https://www.critical-environment.com/company/news/electrochemical-gas-sensors-factors-affecting-life-expectancy): Electrochemical sensors are effective and offer very good performance for monitoring toxic gases and oxygen. Their lifespan depends on seve… - [South Carolina State House](https://www.critical-environment.com/learn/case-studies/south-carolina-state-house): How CETCI gas detection systems protect the historic South Carolina State House parking garage, ensuring safety for staff and visitors in a… - [Technical Training Webinars](https://www.critical-environment.com/learn/training/technical-training-webinars): Join our CET Technical Training Webinars to get real‑time, interactive answers to all your gas detection questions. Enroll with CET. - [CET Certified Factory Training](https://www.critical-environment.com/learn/training/cet-certified-factory-training): Become a Certified Commissioning Technician! A full‑day, hands‑on certification course that equips field technicians with the skills to ins… - [A2L Refrigerant Monitoring Course](https://www.critical-environment.com/learn/training/a2l-refrigerant-monitoring): Learn about A2L refrigerant standards, applications, and gas detection requirements per ASHRAE Standard 15-2024. Enroll with CET. - [Fundamentals of Gas Detection Course](https://www.critical-environment.com/learn/training/fundamentals-of-gas-detection): Educational tool designed to demystify the principles of gas detection for the Consulting Engineering community. Enroll with CET. - [CET Products & Applications Training](https://www.critical-environment.com/learn/training/cet-products-applications-training): Comprehensive training on CET gas detection products and their applications for continuous monitoring. 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