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New exhaust gas laboratory building completed in record time

A new laboratory building for the type examination of motor vehicle exhaust meters

PTBnews 2.2019
Especially interesting for

exhaust gas measuring techniques

motor vehicle workshops, test centers for vehicle inspections and emissions tests

type examinations, local verification offices

The regular inspection of motor vehicle emissions became more stringent in several ways at the end of 2017. This required exhaustive research activities, and numerous type examination certificates for exhaust meters had to be issued or renewed promptly. For this purpose, a new building was planned, erected and commissioned within just one year in order to accommodate a new certification laboratory. This building contains state-of-the-art laboratories for opacimeters and CO meters as well as a laboratory for the calibration of particle counters.

The new building accommodates, among other things, testing laboratories for exhaust meters that are state of the art and a calibration laboratory for particle counters.

German car owners have to prove their car᾽s compliance with the legal emission limits every two years within the scope of the emissions test (“AU”), which is part of the general inspection (“HU”, which the Germans colloquially also call the “TÜV”). This applies both to gasoline engines (which must comply with a maximum emission value for carbon monoxide), and to diesel engines (whose emissions of soot particles are subject to a threshold value). The latter are tested by checking the opacity of the exhaust gas, i.e. the extent to which soot attenuates light irradiated through the exhaust gas is measured.

Exhaust meters are subject to the Measures and Verification Act. For each design, PTB tests a representative type model to see whether it fulfils the strict legal requirements; then a type-examination certificate is issued.

The emissions test process and the emission limits that must be complied with are laid down in the so-called Emissions Test Directive, which the German Federal Ministry of Transport and Digital Infrastructure (BMVI) considerably tightened in September 2017 by adding three new elements:

  1. As of 1 January 2018, the so-called tailpipe test was introduced again without any exceptions.
  2. As of 1 January 2019, the limit values for exhaust gas opacity and CO were halved for all EURO 6 vehicles.
  3. As of 1 January 2021, a new particle number emission limit will be introduced for EURO 6 vehicles.

This tightening of the rules requires exhaustive and time-sensitive research and service activities. Point 3 on the list requires a particle count traceability chain to be set up; point 2 has made an improvement to the traceability of opacimeters, exhaust meters and CO measuring instruments necessary, while the third point necessitated type examinations for a large number of devices. Implementing all these requirements has demanded the immediate modernization as well as increased capacities of testing laboratories for CO measuring instruments and opacimeters.

Therefore, a new 360 m2 laboratory building was planned and commissioned for 4.4 million euros. It consists of two state-of-the-art laboratories where opacity meters and exhaust meters can be tested, as well as a novel calibration laboratory for particle counters. These laboratories allow up to 35 test gases (some of them highly toxic) to be fed sequentially – and mostly automatically – into the measuring instrument under test with great accuracy, and special, metrologically defined test aerosols to be generated. Process automation in particular is promising, since it allows significant acceleration of the test procedures, as well as improvements in terms of measurement quality and occupational safety.


Volker Ebert
Department 3.4
Analytical Chemistry of the Gas Phase
Phone: +49 531 592-3401
Opens window for sending emailvolker.ebert(at)ptb.de