Multi-Gas Detector Selection Guide

Due to rapid developments in technology, it's a difficult selection process for any health and safety manager or instrument engineer. There's also a vast amount of multi-gas detectors to choose from.

In this guide we talk you through the 6 most important points to consider when buying a Multi-Gas Detector.

1. Gases

Firstly, you will need to determine which gas you need to monitor. This information should be available on Material Safety Data Sheets (MSDS). Alternatively, pre-testing may be carried out to understand what’s in the environment.

  • The most common toxic gases include: Ammonia, Carbon Dioxide, Carbon Monoxide, Chlorine, Chlorine Dioxide, Ethylene Oxide, Hydrogen, Hydrogen Sulphide, Hydrogen Cyanide, Methane, Nitric Oxide, Nitrogen Dioxide, Oxygen, Ozone, Phosphine, Propane and Sulphur Dioxide.
  • Multi-gas detectors detect oxygen, toxic gases, and most have a PID sensor option in order to provide a total reading of Volatile Organic Compounds (VOC’s).
  • Infrared IR sensors are used for the measurement of CO2 and in some cases combustible gases.
  • Multi-gas detectors will generally detect 5 or more gases.

2. Detection Range

Secondly, once you know which gases you need to monitor, you will need to know which gas range to detect at. This will be parts per billion (ppb), parts per million (ppm) or percentage volume (%).

3. Weight

Thirdly, multi-gas detectors will be heavier than single and confined space handheld gas detectors due to the number of gas sensors, possibly a sampling pump and the rugged protective casing.

For personal monitoring, consider a gas detector which has a suitable clip for attaching to a harness or clothing otherwise it could easily fall off and potentially damage the unit.

However, some gas detectors are often too heavy to be worn as a personal gas detector, but instead used to carry out assessments as a portable handheld instrument.

4. Sampling Method

Diffusion models of gas detectors are less expensive than models with a built-in pump.

Having a permanent pump can drain the battery quicker and add weight to the instrument.

Consider investing in a gas detector with a slide-on pump which can easily convert when sampling is being carried out in a confined space, then switching off the pump to conserve power when not in use.

5. Data Storage

The two types of data storage is datalogging and event logging.

  • Event logging will only show alarm events. Gas detectors that have event logging will only have capability for a certain number of events.
  • Datalogging allows data to be recorded at given intervals over a period of time.

6. Advanced Features

Advances in technology have vastly improved multi-gas detectors;

  • Intuitive functionality such as 'Man-Down' alarm alerts the control room that a worker has been inactive for a period of time
  • Panic Alarm - By pressing the panic button, a worker will activate the audible and visual alarms letting others in the area know that they need help
  • Plug and play gas sensor options allow for sensors to be quickly swapped out which eradicates the need for multiple devices for use in different applications
  • Wireless - The most significant advantage of wireless gas detection is the ability to broadcast real-time data 24/7 to provide instant results once engaged with a dedicated wireless network.

Download the Multi-gas Detector Selection Guide

  • Classify the types of multi-gas detector
  • Understand the relevant product features
  • Our product recommendations
  • Multi-gas detector comparison guide

View our extensive range of multi-gas detectors