Vehicle Noise

Roadside vehicle and exhaust noise testing with event recording.

For traffic authorities, vehicle noise management depends on accurate data, clear evidence, and full regulatory compliance. Effective enforcement starts with measurements that can be trusted.

Our roadside vehicle and exhaust noise testing system is fully compliant with relevant ISO standards and EU noise directives, ensuring results that stand up to scrutiny and support legally robust decisions. With integrated event recording, individual noise events are captured, providing clear, traceable evidence.

Designed for simplicity in the field, the system is quick to deploy, intuitive to operate, and reliable in continuous operation. This allows authorities to focus on enforcement and policy — not on complex measurement setups.

At a glance

Exhaust noise level

ISO 5130, EU directive 70/157/EEC and §29 StVZO
Annual inspection and survey of road vehicles

Measurement Functions

Noise Level SPL

Measuring the following parameters:
LAFmax
(maximum noise level with A-weighting)
LAeq
(averaged noise level for environmental noise verification)

How to measure?

The environmental noise LAeq shall be at least 10 dB below the measured A-weighted exhaust noise level.
Position the measurement microphone directed towards the exhaust pipe at a distance of 0.5 m at a 45° angle in the same height; the height shall be minimum 0.2 m above ground.
Connect the XL3 Analyzer with the 5 m ASD cable to the measurement microphone.
Start the XL3 with the measurement profile ISO 5130.
Increase the engine speed gradually from idle to the measurement rpm according the table below.
Start the measurement.
Hold the measurement rpm for one second and release the throttle control rapidly, thus the engine speed returns to idle.
The measurement stops automatically after the entire deceleration period.
Repeat the measurement until LAFmax is within 2 dB for three consecutive measurements.
The final result LAFmax is calculated as average of these 3 measurement results.

Rated engine speed	Measurement rpm	Application
< 5000 rpm	75% of rated rpm	road vehicles having at least four wheels
5000 - 7500 rpm	3750 rpm	any road vehicles
> 7500 rpm	50% of rated rpm	any road vehicles