Sound Level Meter Module

The Sensorbee Sound Level Meter (SB4652) adds continuous noise monitoring to the Air Pro 2 environmental monitoring station. At just 10 grams, this module measures sound levels in A-weighted decibels across a comprehensive set of metrics — LAeq, LAFmax, LAFmin, and statistical noise levels (L05 through L95) — providing the data needed for construction noise assessment, planning compliance, and environmental noise management. Compliant with EU noise regulation directives, the module plugs directly into the Air Pro 2 without tools or configuration.

How It Works

The SB4652 captures sound pressure levels through an integrated microphone, sampling the 20 Hz to 10 kHz frequency range. Raw audio data is processed onboard using A-weighting (dBA) to approximate human hearing response, then calculated into the measurement parameters required for environmental noise assessment. The module outputs equivalent continuous sound levels (LAeq), fast-weighted maximum and minimum levels (LAFmax, LAFmin), and a full set of statistical percentile levels (L05, L10, L50, L90, L95) that characterise the noise climate over each measurement period.

Data is transmitted to the Sensorbee Cloud alongside particulate matter, gas, and weather readings from the same Air Pro 2 station — providing a unified environmental dataset from a single device.

Measurement Parameters

The SB4652 delivers the full range of noise metrics used in environmental assessment:

• LAeq — equivalent continuous A-weighted sound level, the primary metric for assessing time-averaged noise exposure over a measurement period
• LAFmax — maximum A-weighted sound level with fast time weighting, capturing peak noise events such as vehicle pass-bys, machinery starts, and impact operations
• LAFmin — minimum A-weighted sound level with fast time weighting, representing the quietest ambient conditions during the measurement period
• L05 — the noise level exceeded for 5% of the measurement period, indicating the loudest typical conditions
• L10 — exceeded for 10% of the period, commonly used as an indicator of traffic noise
• L50 — the median noise level, representing typical ambient conditions
• L90 — exceeded for 90% of the period, widely used as the background noise level for planning assessments
• L95 — exceeded for 95% of the period, representing the minimum ambient noise floor

This combination of metrics supports BS 5228 construction noise assessment, BS 4142 industrial noise evaluation, and general environmental noise surveys.

Why Choose the Sound Level Meter Module

Adding noise monitoring to an environmental station traditionally requires a separate instrument with its own power supply, data logger, and communication system. The SB4652 eliminates this complexity.

• Combined NDV monitoring — noise, dust, and vibration data from a single Air Pro 2 station replaces three separate instruments, reducing equipment costs and site clutter
• Statistical noise levels included — the full L05–L95 percentile set provides the background noise characterisation required for planning assessments and BS 4142 evaluations
• No additional power or data infrastructure — the module draws power from the Air Pro 2 and transmits data through the station's existing cellular connection
• Continuous unattended monitoring — unlike handheld sound level meters that require an operator, the SB4652 monitors continuously and transmits data to the cloud in real time
• Configurable alerts — set noise threshold alerts in the Sensorbee Cloud to receive notifications when measured levels exceed trigger values

Installation

The SB4652 mounts directly onto the Air Pro 2 base unit. Connect the module, and the station detects it automatically — no firmware updates, calibration procedures, or configuration changes are needed. The 10-gram weight adds negligible mass to the monitoring station, and the compact D12.8 × 45 mm housing integrates without affecting the station's wind profile or mounting balance.

For installations where noise is added to an existing Air Pro 2 deployment, the module can be fitted in the field without removing the station from its mounting position.

Applications

• Construction noise monitoring — continuous LAeq and peak level monitoring for BS 5228 compliance on construction and demolition sites, with real-time alerts when noise levels approach or exceed consent conditions
• Planning application support — baseline and impact noise surveys using LAeq, L90 background levels, and statistical metrics for noise impact assessments submitted with planning applications
• Industrial noise assessment — BS 4142 rating level assessments at industrial facility boundaries, combining measured noise data with meteorological parameters from the same station
• Infrastructure projects — noise monitoring alongside roadworks, rail, tunnelling, and utility projects where continuous unattended measurement is required over extended periods
• Community noise management — real-time noise data for community liaison, complaint investigation, and proactive management of noise-sensitive operations near residential areas
• Airport and transport noise — continuous monitoring of noise from aircraft, rail, and road traffic at sensitive receptor locations

Frequently Asked Questions

Does the Sound Level Meter meet BS 5228 requirements?

The SB4652 provides the LAeq and peak level measurements specified in BS 5228 for construction noise assessment. It delivers continuous unattended monitoring suitable for indicative noise management on construction sites.

Can I add this module to an existing Air Pro 2?

Yes. The SB4652 is a plug-and-play module that connects to the Air Pro 2 at any time. No station replacement, firmware update, or reconfiguration is needed.

What is the difference between LAeq and L90?

LAeq is the equivalent continuous sound level — an energy-averaged representation of all noise over the measurement period. L90 is the level exceeded for 90% of the period, representing the background noise with intermittent louder events excluded. Both metrics are essential for environmental noise assessment.

Does it work in rainy conditions?

The module is rated for 0–99% RH and operates across -20 to +60°C. The polyamide housing protects the microphone element from moisture ingress during normal outdoor exposure.

Can I set noise alert thresholds?

Yes. The Sensorbee Cloud platform supports configurable threshold alerts for all noise metrics. Set trigger levels for LAeq, LAFmax, or any statistical parameter, and receive notifications via email or the cloud dashboard when thresholds are exceeded.