Skip to content
AkerminMeasure. Monitor. Improve. Compare Products
Review

Extech EN300 Review: Five-in-One Environmental Meter for Field Work

The Extech EN300 packs five environmental measurements into one meter for people who audit rooms rather than specialise in one parameter. This review explains what each function is good for, where a combined meter falls short of a dedicated instrument, and who should buy it.

By the Akermin Editorial Team · 4 min read

As an Amazon Associate, Akermin earns from qualifying purchases. Product links on this page are affiliate links.

Extech EN300 Review: Five-in-One Environmental Meter for Field Work

Extech · Extech EN300 5-in-1 Environmental Meter - Measures Air Velocity, Light, Humidity, Temperature & Sound Level - Compact Multi-Function Tester with Large LCD & Data Hold for Field and Indoor Monitoring

View on Amazon

Price and availability are shown on Amazon and can change at any time.

Verdict

The EN300 is a generalist’s meter. It measures air velocity, light, relative humidity, temperature and sound level, shows them on a large LCD with data hold and min/max, and runs on standard batteries. For a facilities manager, a school estates officer or an HVAC technician doing a first-pass room survey, having all five in a pocket is the point. Each function is a screening measurement rather than a specialist one: the sound reading is not a classified Type 2 measurement, the light sensor is not a calibrated photometer and the anemometer is a vane for diffusers and ducts rather than a hot-wire probe. Buy it for coverage, and add a dedicated meter for any parameter that has to stand up to scrutiny.

Who It Is For

  • Facilities and estates staff auditing classrooms, offices and meeting rooms.
  • HVAC technicians who want airflow, temperature and humidity in one hand during commissioning.
  • Health and safety officers doing preliminary noise and light checks before calling in a specialist.

Documented Specifications

Item Documentation
Measurements Air velocity, light intensity, relative humidity, temperature, sound level
Display Large LCD showing multiple parameters
Functions Data hold, min/max
Operation One-handed
Power Standard batteries

The Five Functions in Use

Air velocity

The vane anemometer is intended for supply diffusers, return grilles and open ducts. It gives velocity, and with the duct area it gives a volume flow estimate, which is the basic commissioning check for a ventilation system.

Light

The light function reports illuminance for desk, corridor and classroom checks against typical recommended levels. For LED-specific measurement or audits that will be filed, a dedicated light meter such as the Extech LT300 is the right tool; see how to choose a light meter.

Humidity and temperature

These are the two readings most often used together, because comfort and mould risk depend on both. The EN300’s sensor needs a minute or two to settle after moving between rooms. Our guide on measuring relative humidity correctly covers the technique.

Sound level

The sound function tells you whether a plant room, a classroom or an open office is loud enough to look at further. It is not a substitute for a Type 2 meter in a noise assessment. See choosing a sound level meter.

Display and Handling

The large LCD shows more than one parameter, so temperature and humidity can be read together. Data hold freezes a reading when the display cannot be seen at the measurement point, and min/max recall captures the range across a sweep of a room. Owners describe the meter as simple to operate with one hand, which matters on a ladder at a diffuser.

A Typical Room Audit With the EN300

A classroom audit illustrates how the five functions work together. Temperature and humidity are read at desk height in the centre of the room after the meter has settled. Light is read on the desk surface at several positions, noting the minimum. Sound is read during a normal lesson and again with the ventilation running and the room empty, which separates plant noise from occupancy noise. Air velocity is read at the supply diffuser to confirm the system is delivering air at all. The whole exercise takes ten minutes per room, and the min/max recall means the extremes are captured without a notebook. Any parameter that fails is then measured again with a dedicated instrument before money is spent. Our classroom CO₂ monitor guide covers the one measurement the EN300 does not make, which is often the one that explains a stuffy room.

Strengths

  • Five parameters in one pocket-sized meter.
  • Large multi-parameter display with hold and min/max.
  • Standard batteries and one-hand operation.

Limitations

  • Each function is a screening measurement, not a specialist one.
  • No PC datalogging.
  • Sound reading is not a classified measurement for compliance.

How It Compares

The testo 605i is a humidity and temperature probe that reports to a phone, better for duct work but single-purpose. The Extech SL510 is a Class 2 sound level meter for noise work. The Extech LT300 is a dedicated light meter. The EN300 replaces none of them for specialist work; it replaces carrying all of them for a first look.

How We Research

This review is based on Extech’s published specifications, the Amazon listing and owner reports. We did not run laboratory tests. Where a numerical accuracy is needed for a specific function, consult the Extech datasheet.

Testo 605i Thermohygrometer - Hygrometer & Indoor Thermometer for Humidity Measurement and Indoor Temperature - 90° Bendable In-Duct Temperature and Humidity Monitor with Bluetooth - iOS & Android

Testo 605i Thermohygrometer - Hygrometer & Indoor Thermometer for Humidity

View on Amazon
Extech SL510 Sound Level Meter, 35-130 dB, Class 2

Extech SL510 Sound Level Meter, 35-130 dB, Class 2

View on Amazon
Extech LT300 Light Meter, Remote Sensor, Peak and Relative Modes

Extech LT300 Light Meter, Remote Sensor, Peak and Relative Modes

View on Amazon

Products shown because their documented specifications fit this guide. Price and availability are on Amazon and can change.

Frequently Asked Questions

What does the EN300 measure?

Air velocity, light intensity, relative humidity, temperature and sound level, according to the listing.

Is the sound function a proper sound level meter?

It gives a sound level reading for comparative and screening use. For compliance measurements a dedicated Type 2 meter such as the Extech SL510 is the appropriate instrument.

Does it log data?

The listing describes data hold and min/max recall, not datalogging to a PC.

What is it best for?

Quick room audits: checking airflow at a diffuser, light at a desk, humidity and temperature in a classroom, and whether a space is noisy, all with one tool.

Affiliate disclosure: Akermin earns a commission from qualifying Amazon purchases made through links on this page. Our editorial picks are based on documented specifications and owner feedback, not commissions.