testo 535 - Versatile C02 Measurement 

Order-Nr.  0560 5350

  • Quick and accurate CO2 measurements 

  • Long-term measurements using max and average values 

  • Long-term stable, maintenance-free infrared sensor 

  • Optional testo fast printer for print outs on site 

The testo 535 Versatile CO2 Measurement comes with a permanently attached sensor and is designed specifically for monitoring and optimising the ambient air. 

Product Description

The Testo 535 is an efficient CO2 measuring instrument for measuring indoor air quality. Bad air quality in rooms can lead to tiredness, lack of concentration and illness (Sick Building Syndrome) due to high CO2 concentration (greater than 1000 ppm)
  • Long-term monitoring based on maximum and mean calculation
  • Long-term stable 2 channel infrared sensor
  • Highly accurate, highly efficient
  • Repeated calibration is unnecessary
The average  person spends about 90 percent of their time in closed rooms. It is no small wonder then that the room climate often has a considerable effect on the way we feel and also on our health and our wellbeing. There’s a massive difference if the air – in an office for example – is fresh and invigorating or whether it’s heavy and stale. Stale and heavy air causes fatigue and tiredness as well as considerable discomfort. It can also lead to lack of concentration and actually have a detrimental effect on your health. The Testo 535 CO2 meter is designed to measure the CO2 concentration in the ambient air because stale air has a much higher CO2 concentration than fresh air. 

Areas of application and benefits of the testo 535 CO2 meter

The Testo 535 CO2 meter is ideal for monitoring and optimising the room climate, i.e. in offices. It can also be used to check if existing air conditioning and ventilation systems are providing the relevant rooms with enough fresh air.

The high-precision, long-term stable, 2-channel infrared sensor measures the CO2 concentration in the ambient air. Because the 2-channel infrared sensor is maintenance-free, it can also be used to carry out long-term measurements. The readings from such measurements can be analysed using the minimum, maximum and average values. All these values can be displayed at the touch of a key.

The optional testo turbo printer can provide you with measuring data print outs that include both the time and date while you are still on site. And the optional TopSafe protective cover protects your meter against impact and dirt and water ingress. 


Delivery Scope

testo 535 CO2 meter with permanently attached sensor, calibration certificate, batteries.

Ambient CO₂

Measuring range

0 to 9999 ppm

0 to 0.999 Vol.%


0 to 5000 ppm: ±(75 ppm + 3 % of mv)

5001 to 9999 ppm: ±(150 ppm + 5 % of mv)


1 ppm

0.001 Vol.%

General technical data


190 x 57 x 42 mm

Operating temperature

0 to +50 °C



Measuring medium


Auto-off instrument

10 min

Battery type

9V block battery

Battery life

6 h

Display type


Display size

2 lines

Storage temperature

-20 to +70 °C


300 g

Transport and Protection