The sensor measures total mass concentration values for PM1, PM2.5, PM4 and PM10, each in µg/m³.

• PM1 and PM2.5 — the fine fractions. Small enough to stay airborne, travel through a facility and reach board level, and small enough to pass through lower grade filtration.


• PM4 and PM10 — the coarse fractions. These settle out faster and are what visibly accumulates on surfaces, grilles and heat sinks.


• Why separate them: the two groups have different sources, different filtration responses and different consequences. A single combined figure cannot distinguish a filter that has stopped catching fines from one that is simply loaded.

A compact and affordable optical particle sensor, with the sensing element made in Switzerland.

• Nothing consumed: the measurement is optical, so there is no filter cassette to weigh, replace or send away for gravimetric analysis.


• Continuous: concentrations are reported in real time rather than as an average over a sampling period.


• Compact: small enough to mount inside a cabinet, where the particle level actually matters for the equipment.

Air particles are one of the four main contributors to corrosion, alongside temperature, humidity and corrosive gases.

• The G1 target: for a mild ANSI/ISA 71.04 environment, particles from PM1 to PM10 should be held below 70 µg/m³. The limit is expressed across that fraction range, which is exactly what this sensor covers.


• Particles carry contaminants: settled dust holds moisture and corrosive compounds against the board surface, which is where the reaction happens.


• Warranty exposure: manufacturers routinely void warranty where damage is attributable to corrosion, making the environmental record worth having.

See the ENV-CORROSION for direct measurement of the resulting corrosion class.

Particles are the mechanism by which cooling performance degrades without anything appearing to break — and fraction data tells you which part of the system is at fault.

• Filter grade: coarse fractions held down while fine fractions climb points at the filter specification rather than the filter's condition.


• Filter loading: all fractions rising together, gradually, is loading — the filter is working and approaching replacement.


• Obstructed airflow: particles on heat sinks, fan blades and intake grilles reduce the heat actually carried away, even where fans are still running normally.


• Maintenance on evidence: filter changes scheduled against measured concentrations beat changes scheduled against the calendar, in both directions.

Pair with the ENV-AIRFLOW to see both the cause and its effect on air velocity.

Particle levels vary far more within a facility than temperature does, so placement decides what the reading is worth.

• Inside cabinets: what reaches the equipment is not what a room-level reading reports.


• At intake plenums: immediately downstream of filtration, to see what is getting through.


• Near doorways and loading points: the routes by which outside air and traffic bring particles in.


• Adjacent to building work: construction, drilling and ceiling work produce short, severe particle events that a periodic inspection will miss entirely.

Application Guide

The ENV-PARTICLE connects to the base unit, which makes it an Ethernet sensor. The base unit is a standalone device with its own IP address in your network. On its own it monitors the sensor and triggers alerts via email, SNMP or optional SMS when needed.

There is no software or PC required for the sensor to run.

With our optional Monitoring Software you can centrally monitor sensors with trending and more. This is optional and not required.

The ENV-PARTICLE resolves particulate by fraction. A full picture of a mission critical environment usually needs a few more sensors.

• ENV-DUST — a single total dust density figure where fraction detail is not required.


• ENV-CORROSION — measures the resulting ANSI/ISA corrosion class directly, over a rolling 30 day window.


• ENV-AIRFLOW — shows whether particle loading is starting to restrict air movement.


• ENV-THUM — temperature and humidity, the other two contributors to corrosion.