Gas detection in underground car parks

Gas detection in underground car parks

Most of the modern cars still have internal combustion engines that run on petrol or diesel fuel. The products of internal combustion are toxic gases that accumulate in enclosed spaces such as underground car parks. Essential requirement of the safety system for underground parkings and garages is hazardous gases monitoring and ventilation. Acceptable gas concentration levels are established by local regulatory agencies and codes.

Which gases should be measured?

Carbon Monoxide (CO) is measured as international standard in enclosed car parks and garages, as it is a combustion product of petrol and diesel engines. Carbon Monoxide is odourless, colourless and tasteless so it’s impossible to detect its presence without monitoring equipment. Maximum allowable short term CO concentration in enclosed spaces is 150 ppm.

Along with Carbon Monoxide, measurement of a toxic Nitrogen Dioxide (NO2) is often required, as NO2 is produced from diesel vehicles. If local codes do not have any requirements for Nitrogen Dioxide detection in parking garages, it is still a good idea to know that mitigation of this gas is a very important component of safety in underground car parks. Maximum allowable short term concentration for NO2 – 15 ppm.

Сommon problem with measuring Nitrogen Dioxide is the frequent electrochemical sensor replacement. The new E2615-NO2 Evikon MCI detectors use the latest and most advanced electrochemical sensors with more than 5 years life-time.

Although NO2 measurement is a more classical method, CO2 detection is still widespread in some countries. Carbon Dioxide (CO2) comes from diesel and petrol fuels combustion together with other toxic gases and its level correlates with them. While the level of CO2 typically found in enclosed car parks is not considered to be dangerous, it is measured as an indicator of other hazardous gases, in particular NO2.

Benefits of installing Evikon MCI gas detectors

Building owner

Gas detectors help to control the permissible toxic gases concentrations in accordance with local regulations.

Constant operation of the underground car park ventilation system means high energy consumption; frequent motor maintenance and, consequently, shortened fan life; heat energy loss due to high air exchange. Evikon MCI gas detectors help to understand when ventilation needs to be switched on and off, depending on the gas concentration in the air. This significantly reduces energy costs and regulates the air exchange.

Evikon MCI sensors also do not require recalibration, which reduces maintenance costs.


Easy to install IP65 enclosures

PluraSens® Platform that has two analog outputs (settable to 4-20 mA or 0-10 V) and RS485 Modbus RTU digital interface

Convenient and fast calibration process

Part of the products are maintenance free

Short lead times


Toxic gases accumulation is unsafe for underground car parks visitors. Gas detectors participate in ventilation and alarm control by hazardous gases measurement. This helps to maintain acceptable levels of Carbon Monoxide (CO), Nitrogen Dioxide (NO2) or Carbon Dioxide (CO2). Measurement of toxic gases creates a safe breathing environment and improves air quality in enclosed car parks.

Noise from fans, too cold or too warm air can make people feel uncomfortable. Evikon MCI gas detectors solve this problem by helping to control the operation time of ventilation systems.

Evikon MCI gas detectors for parking garages

Excellent combined solution for underground car parks - dual gas transmitters - E2660-CO-NO2 and E2660-CO-CO2.

• Dual transmitters reduce installation time and the number of products required (especially in large underground car parks).
• Two analog outputs 4-20 mA and 0-10 V and RS485 Modbus RTU digital interface can be used to connect the transmitter to safety or building automation systems.
• Two relays with closing contact (optional) may be used for remote signaling or concentration control (two alarm set-points are user settable).
• Easy to install IP65 enclosures save installation time.
• Remote sensor option for E2660-CO-CO2.

Cost effective solution - E2615-CO and E2615-NO2 transmitters.

• Low cost for volume HVAC applications.
• Miniature long-life electrochemical sensors do not require calibration for 5 years. This reduces maintenance costs.
• User selectable 4-20mA / 0-10V output (optional) is compatible with automation systems.
• Compact wall-mount and easy to install IP65 enclosures save installation time.

Multifunctional intelligent transmitters for demanding customers - E2618-CO, E2618-NO2 and E2618-CO2.

• Two analog outputs (settable to 4-20 mA or 0-10 V) and RS485 Modbus RTU digital interface for Fieldbus networking can be used to connect the detectors to safety or building automation systems.
• Duct-mount and remote probe options.
• Fully calibrated and temperature compensated gas sensors provide excellent repeatability, stability and long lifetime.

Gas detectors can be selected individually, depending on the request. A wider range of Evikon MCI gas detectors for parking garages can be explored by following the links: CO, NO2, CO2.

In addition to gases measurement in underground car parks, humidity measurement is an added advantage. You can read about this in the next article.

Evikon MCI jointly with a sister company Evikontroll Systems can offer full solutions as well. For more technical information / inquiries, please contact our distributors / sales partners.