VOC sensors

A ventilation system equipped with VOC sensors can optimize indoor air quality while minimizing energy consumption. Our AERASGARD® VOC sensors detect indoor air pollution from contaminated gases such as cigarette smoke, breathing, paints, cleaning agents, office supplies, bodily functions, etc.

Guide and interesting facts about VOC sensors

VOC
AERASGARD® RLQ-SD-U

1501-61C0-1001-500
0...100 % air quality - VOC sensitivities (low/medium/high)
Air quality (VOC)
0 - 10 V
IP 30
$214.88

incl. VAT $255.54
VOC
AERASGARD® RLQ-W

1501-61C0-7301-500
0...100 % air quality - VOC sensitivities (low/medium/high)
Air quality (VOC)
0-10V / 4..20mA + changeover contact
IP 30
$225.22

incl. VAT $267.97
VOC
AERASGARD® RLQ-W-A

1501-61C0-7331-500
0...100 % air quality - VOC sensitivities (low/medium/high)
Air quality (VOC)
0-10V / 4..20mA + changeover contact
IP 30
$256.95

incl. VAT $305.59
VOC
AERASGARD® KLQ-SD-U

1501-3170-1001-500
0...100 % air quality - VOC sensitivities (low/medium/high)

Air quality (VOC)

0 - 10 V

IP 65
$264.96

incl. VAT $315.12
VOC
AERASGARD® KLQ-W

1501-3150-7301-500
0...100 % air quality - VOC sensitivities (low/medium/high)

Air quality (VOC)

active (0 -10 V / 4...20 mA), changeover contact

IP 65
$276.57

incl. VAT $329.01
VOC
AERASGARD® RLQ-W VA

1501-61C0-7301-505
0...100 % air quality - VOC sensitivities (low/medium/high)

Air quality (VOC)

active (0 -10 V / 4...20 mA), changeover contact

IP 30
$360.15

incl. VAT $428.55
CO2 VOC
AERASGARD® RLQ-CO2-W

1501-61B1-7301-500
0...2000 ppm / 0...5000 ppm
0...100 % air quality - VOC sensitivities (low/medium/high)
Air quality (VOC), carbon dioxide (CO2)
0-10V / 4..20mA + changeover contact
IP 30
$468.05

incl. VAT $556.97
CO2 VOC
AERASGARD® KLQ-CO2-W

1501-8111-7301-500
0...100 % air quality - VOC sensitivities (low/medium/high)
0...2000 ppm / 0...5000 ppm
Air quality (VOC), carbon dioxide (CO2)
active (0 -10 V / 4...20 mA), changeover contact
IP 65
$486.68

incl. VAT $579.02
CO2 VOC
AERASGARD® RLQ-CO2-Modbus

1501-61B1-6001-500
0...100 % air quality - VOC sensitivities (low/medium/high)
0...5000 ppm
Air quality (VOC), carbon dioxide (CO2)
Modbus RTU
IP 30
$498.21

incl. VAT $592.83
°C %RH +2
AERASGARD® RFTM-LQ-CO2-W

1501-61B8-7301-500
0...2000 ppm / 0...5000 ppm
0...100 % air quality - VOC sensitivities (low/medium/high)
Temperature, relative humidity,
air quality (VOC), carbon dioxide (CO2)
active (0 -10 V / 4...20 mA), changeover contact
IP 30
$513.28

incl. VAT $610.75
CO2 VOC
AERASGARD® KLQ-CO2-Modbus

1501-8111-6001-500
0...100 % air quality - VOC sensitivities (low/medium/high)
0...5000 ppm
Air quality (VOC), carbon dioxide (CO2), atmospheric air pressure
Modbus RTU
IP 65
$528.37

incl. VAT $628.69
CO2 VOC
AERASGARD® RLQ-CO2-W LCD

1501-61B1-7321-500
0...2000 ppm / 0...5000 ppm
0...100 % air quality - VOC sensitivities (low/medium/high)
Air quality (VOC), carbon dioxide (CO2)
0-10V / 4..20mA + changeover contact
IP 30
$530.18

incl. VAT $630.88
CO2 VOC
AERASGARD® KLQ-CO2-W LCD

1501-8111-7371-500
0...100 % air quality - VOC sensitivities (low/medium/high)
0...2000 ppm / 0...5000 ppm
Air quality (VOC), carbon dioxide (CO2)
active (0 -10 V / 4...20 mA), changeover contact
IP 65
$560.23

incl. VAT $666.63
CO2 VOC
AERASGARD® RLQ-CO2-Modbus LCD

1501-61B1-6021-500
0...100 % air quality - VOC sensitivities (low/medium/high)
0...5000 ppm
Air quality (VOC), carbon dioxide (CO2)
Modbus RTU
IP 30
$560.33

incl. VAT $666.73
°C %RH +2
AERASGARD® RFTM-LQ-CO2-W LCD

1501-61B8-7321-500
0...2000 ppm / 0...5000 ppm
0...100 % air quality - VOC sensitivities (low/medium/high)
Temperature, relative humidity,
air quality (VOC), carbon dioxide (CO2)
active (0 -10 V / 4...20 mA), changeover contact
IP 30
$575.41

incl. VAT $684.66
°C %RH +2
AERASGARD® KFTM-LQ-CO2-W

1501-8118-7301-500
0...2000 ppm / 0...5000 ppm
0...100 % air quality - VOC sensitivities (low/medium/high)
Temperature, relative humidity,
air quality (VOC), carbon dioxide (CO2)
active (0 -10 V / 4...20 mA), changeover contact
IP 65
$583.29

incl. VAT $694.06

VOC sensor for building automation & indoor air monitoring

Reliably detect volatile organic compounds (VOCs) and control them as required

Author: S. Becker | Status: 13.03.2026

Briefly explained:
A VOC sensor measures the concentration of volatile organic compounds (VOCs) in indoor air. These substances are produced by furniture, building materials, cleaning agents, printers, paints or human activities, among other things.

In building automation, a VOC sensor thus provides important information about the actual air quality in the room - not only about occupancy, but also about the chemical contamination of the room air.

Especially in modern, densely built buildings, VOC measurement is a relevant component for:

Demand-based ventilation control
Comfort optimization
Energy efficiency
Monitoring in sensitive areas

Content

What exactly does a VOC sensor measure? Typical applications of VOC sensors in BMS & room automation Selection guide: What should you look out for in a VOC sensor? VOC sensor in modern building concepts

Why is a VOC sensor useful in building automation?

While CO2 is primarily an indicator of occupancy, a VOC sensor records the total pollution of the room air by organic compounds.

This is particularly relevant in:

New buildings (outgassing of materials)
renovated buildings
Meeting rooms with changing use
Schools, kindergartens
Hotels, waiting areas
Offices with a high level of technical equipment

A VOC sensor helps to detect situations in which the air quality is subjectively perceived as "poor" - even though CO2 values are still within the normal range.

What exactly does a VOC sensor measure?

VOC sensors usually detect the so-called:

TVOC concentration (Total Volatile Organic Compounds)

Typical influencing factors:

Solvent
Cleaning agent
Furniture and building material vapors
Cosmetics
Emissions from printers or technical devices

The measured values are often referred to as:

Index value
ppm
µg/m³ (depending on system and evaluation)

provided.

Important in building automation:
VOC is not a single gas, but a collective value for organic compounds - the interpretation is therefore always made in the context of the application.

IAQ assessment according to the Federal Environment Agency

Optionally, the assessment is not only carried out as a percentage, but also as an IAQ level (1-5) in accordance with the TVOC guidelines of the German Federal Environment Agency. This allows specific ventilation measures to be derived - from "no measure required" to "intensive ventilation required".

Typical applications in BMS & room automation

In building automation, a VOC sensor is typically used for

Demand-based ventilation adjustment
Air quality monitoring in sensitive areas
Trend recording and analysis
Alarm in the event of increased emission values
Combination with CO2, temperature and humidity measurement

VOC measurement is particularly useful in rooms where the air quality is not solely dependent on occupancy.

Integration in building automation & field device structures

A VOC sensor is a classic field device and is integrated via depending on the system environment:

Analog interfaces

0-10 V
4-20 mA
Potential-free changeover contact

Digital bus systems

The decisive factor is that the measured value is not only displayed in the BMS, but also used for control purposes.

Selection guide: What should you look out for in a VOC sensor?

The selection of a VOC sensor is less trivial than with CO2, as it is a collective parameter.

Long-term stability & drift behavior
Metal oxide VOC sensors react sensitively to temperature, humidity and changing room air conditions. Without a suitable calibration strategy, measured values may drift over time.
The AERASGARD® VOC sensor works with permanent self-calibration.
The reference point is automatically adjusted by regular fresh air calibration - for long-term stable measured values. The typical sensor service life is over 60 months under normal load.
Response time
For dynamic ventilation control, the measurement dynamics should match the control strategy.
Installation situation
Installation at a representative room height - not in the direct vicinity of emission sources or ventilation outlets.

Installation instructions for precise VOC measurement

Gas exchange takes place via diffusion.
A minimum flow velocity of 0.3 m/s is required for a fast response time. The installation must be carried out in such a way that the air flow presses into the duct pipe - negative pressure situations must be avoided.