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Carbon Dioxide Monitor MD-21

Carbon Dioxide Monitor MD-21

Regular price £32.00
Regular price Sale price £32.00
VAT included
FREE delivery for all orders
  • Measure CO2 levels in your home or workplace
  • Detect poor air quality before discomfort occurs
  • Identify where and when to improve ventilation
  • Helps you to reduce respiratory virus risk
  • Audible and visual alarm, with mute and screen dim
  • USB powered, with a rechargeable battery backup

What's in the box?

  • CO2 monitor with internal rechargeable battery
  • Detachable stand
  • Micro USB cable (1 metre long)
  • User manual (English, French, German, Dutch)
Please note: a USB power source such as a mains adapter (not included) is required to power or recharge this product.

Delivery & Returns

All UK orders have FREE 3-5 day standard delivery.
An express 1-2 day delivery is also available at the checkout.
For further details, please see our Delivery Policy.

Please contact us within 14 days of delivery if you wish to return an item. Further details are given in our Returns & Refunds Policy.

View full details
    • Measure CO2 levels in your home or workplace
    • Detect poor air quality before discomfort occurs
    • Audible and visual alarm, with mute and screen dim

    • Identify where and when to improve ventilation
    • Helps you to reduce respiratory virus risk
    • USB powered, with a rechargeable battery backup

Collapsible content

What's in the box?

  • CO2 monitor with internal rechargeable battery
  • Detachable stand
  • Micro USB cable (1 metre long)
  • User manual (English, French, German, Dutch)
Please note: a USB power source such as a mains adapter (not included) is required to power or recharge this product.

Delivery & Returns

All UK orders have FREE 3-5 day standard delivery.
An express 1-2 day delivery is also available at the checkout.
For further details, please see our Delivery Policy.

Please contact us within 14 days of delivery if you wish to return an item. Further details are given in our Returns & Refunds Policy.

With our CO2 monitor you can...

  • Enhance comfort and reduce heating costs through better management of ventilation.
  • Get an early warning of worsening air quality, take preventive action, then track the improvement.
  • Adapt and plan the use of your indoor areas for better long-term well-being.
  • Gain reassurance and certainty about air quality.

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Specifications

Sensor typeNon-dispersive infrared (NDIR)
Measurement range420 – 5000 ppm
Accuracy± 50 ppm ± 3% of reading
Response time2.0 minutes for 90% of step-change
Dimensions10 cm x 9 cm x 6 cm (W x H x D)
Power sourceUSB and internal rechargeable battery
Battery run timeUp to 9 hours
Battery recharge time3 hours (typical)
Calibration methodManual and automatic
Alarm typeAudible and visual
Alarm disable/muteYes
Alarm levels800 ppm, 1200 ppm (default, can be changed)

Locations for use

How do I use it?

Place the monitor in any indoor area where people are present.

Check the air quality rating colour from time to time. A yellow or red light prompts you to improve ventilation, reduce overcrowding, or take a break outside.

If you forget to check, the audible alarm will warn you of high CO2 levels (alarm can be silenced if preferred).

You can also read the CO2 concentration, measured in parts per million (ppm), at any time.

Air quality levels

How does it work?

  1. The monitor contains a sensor which accurately measures the CO2 content of the air.
  2. When the CO2 measurement exceeds a preset threshold, the indicator light changes from green to yellow.
  3. CO2 exceeding a second threshold causes a red light and triggers the alarm.


We have selected the thresholds according to UK health authority advice. However, you can set new values if desired.

A happy family

Why is this important today?

Modern buildings are increasingly airtight to improve energy efficiency. This reduces passive ventilation and leads to air quality problems.

Meanwhile, coronavirus has raised awareness of the link between ventilation and respiratory infections.

CO2 monitoring helps you to address these concerns and achieve better air quality.

Please note

  • A USB power source such as a mains adapter (not included) is required to power or recharge this product.
  • This product does not detect the poisonous gas carbon monoxide (CO).
  • CO2 monitors cannot detect or reduce airborne disease directly, but are used to guide actions which improve and manage ventilation.
  • Battery run and recharge times depend on the device age and pattern of use.
  • The specified measurement accuracy requires correct completion of the calibration procedure.

  • FREE DELIVERY

    and tracking for all UK orders

  • SECURE CHECKOUT

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  • 24 HOUR DISPATCH

    from our UK warehouses

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