Portable Gas Detectors

Seki Hudson

2 months ago

Gas detection plays a major role in protecting life and property at homes and industrial complexes. Portable gas detectors probably account for nearly half of all modern electronic gas detectors.

In this post, I will explain portable gas detectors, when and where to use them, tips on selecting a suitable gas detector, and more.

What are portable gas detectors?

Portable gas detectors are mobile devices personnel use for pre-entry gas level checks. Each portable device will test gas levels in an area to ensure it is safe for human entry.

These are gas detectors that you can carry and move with you when you move in other words are Personal Protective Devices (PPE) that are designed to protect you from Toxic gases, flammable gases, or Oxygen depletion.

What to look for on a portable gas detector?

There are a lot of great portable gas detectors in the market and selecting the right one for your needs can be a complicated task. If you want a portable gas detector, here are a few things you should look for.

Robustness and lightweight

If you or someone who works with you will use this gas detector, you need to make sure that it is robust and lightweight so that it can be easier to operate and carry while performing other tasks.

You do not want your gas detector to be so heavy that it can hinder your movement, especially during an emergence.

Data logging and self-checking

A portable gas detector must have data logging capability and the ability to self-diagnose.

The data logging capability will help you evaluate historical data from the unit, analyze when it was calibrated, and determine when and what the reading was if there was an alarm.

Also, in case of an accident, it is easy to evaluate the situation by downloading the data log to explain it to your superior, authority, or insurance company.

A gas detector with a self-checking mechanism will perform a self-check once per given time, and if something is not working as it should, it will send you an alarm. This feature can help save lives and properties, and please ensure your gas detector has it.

Simple to service

You want to ensure that the portable gas detector you buy is simple to use and service. You want your technicians to be able to service the unit with minimum training.

You do not want to send your device to a service center for simple services like changing the sensor or calibration, because this will cost you money and time to send and receive your portable gas detectors.

Long battery life

Another aspect to look for in portable gas detectors is the battery life. Most countries have an 8-hour working shift system, so you want to ensure that the unit will last at least 8 hours if it is fully charged.

If you can get one that will last at least 16 hours, it will be even better ( considering temperature and alarms).

You do not want your gas detector to drain the battery before your shift ends and spend time charging your units. Make sure that if you have an 8-hour shift, your gas detector can handle at least double that time. This is because alarms might drain the unit’s battery faster.

Best Portable Gas Detectors for Accurate and Reliable Detection

Why Portable gas detectors are essential?

Portable gas detectors are classed as Personal Protective Equipment (PPE) designed to keep personnel safe from gas hazards and allow mobile testing of locations they entered.

These small devices are essential in many areas where gas hazards could occur because they are the only means of continuously monitoring an operator’s breathing zone while stationary and moving.

Areas where you can use portable gas detectors

Here are a few areas where you can use portable gas detectors.

The area may not be entered by personnel very often

Suppose there is an area where personnel may not enter very often, and there is no justification for implementing a fixed gas detection system. In that case, you will need a portable gas detector.

In small areas, it is hard to reach

If you work in small areas such as confined spaces, tunnels, gas pipes, etc, where they are small and hard to reach, portable gas detection would be the best solution.

Nonstationary applications

You need portable gas detectors to detect gas in moving gas tankers or to protect firefighters from Oxygen depletion.

Typical gases requiring portable detection

The most commonly detected gases include:

Carbon Monoxide (CO)
Carbon Dioxide (CO2)
Hydrogen Sulphide (H2S)
Oxygen Depletion (O2)
Flammable gases include Methane, Liquid Petroleum Gas (LPG), and Liquid Natural Gas (LNG).
Ammonia (NH3)
Sulfur Dioxide (SO2)
Chlorine (Cl2)
Chlorine Dioxide (ClO2)
Nitrous Oxide (NO)
Nitrous Dioxide (NO2)
Phosphine (PH3)
Hydrogen Cyanide (HCN)
Ozone (O3)
Volatile Organic Compounds (VOC), including Acetone, Benzene, Toluene, and Xylene

What are the types of portable gas detectors?

Portable gas detectors are usually divided into single and multiple gas detectors.

Single gas detectors

As their name suggests, single gas detectors have just one sensor for detecting a certain gas.

Multiple gas detectors

Multiple gas detectors can detect more than one gas in a single unit, and they usually contain up to 6 different sensors to detect multiple gases.

The most common ones are oxygen, Flammable, Carbon Monoxide, and Hydrogen Sulphide.

Also, we can categorize portable gas detectors according to their ability to be serviceable or not.

Serviceable gas detectors

These are serviceable gas detectors, which means that if something in the unit goes bad ( sensor, PCB, etc.), you can buy a replacement and fix the issue.

Disposable gas detectors

Some portable gas detectors are not serviceable, which means that if something goes wrong with the unit, the only solution is to replace the whole unit.

There is no way to fix it. Most manufacturers who offer disposable units will replace the unit for you if it is under warranty.

Most of the disposable gas detectors can not be turned off after turning on the unit, and the only maintenance they will need is a bump check and sometimes calibration.

Operation modes for portable gas detectors

Portable gas detectors can draw air in (known as sampling) or allow air to diffuse into the sensor ( known as diffusion).

Diffusion mode

This is the mode in which a portable gas detector allows the air to diffuse into the sensor so the unit can see ( detect the gas).

Select a diffusion gas detector if your application requires it to protect the person’s breathing zone.

Sampling mode

In this mode, the detector contains a built-in motorized pump or an aspirator pump to help it draw air toward the sensor.

The air can be drawn in either by using a built-in motorized bump or manually, and this is critical when an area may contain hazards because it allows an operator to check the air for gases before entering and breathing the air in.

Maintainance of portable gas detectors

Portable gas detectors will require some maintenance to keep them running without problems.

Bump check

A bump check ( or bump test) is a functional test on the unit to ensure the sensors and alarms are working.

For safety reasons, it is recommended to bump-check your portable gas detector each day before using it.

What Is A Bump Test In Gas Detection?

Cleaning

Make sure your portable gas detector is free from dust. Clean it when possible, but do not use water or soap, which may damage the detector. Use a dry, clean cloth to clean it.

Calibration

It is recommended to calibrate your gas detector at least once per year, and most manufacturers will tell you what their recommendation is when it comes to portable gas detector calibration; please follow the manufacturer’s instructions on this.

Depending on your industry the calibration frequency can vary, you need to calibrate your unit according to the manufacturer’s instructions and for best practices, calibrate the unit each time it fails the bump test.

Gas Detector Calibration

Sensor replacement

If you have a serviceable portable gas detector, you may need to replace the sensor when it starts failing; replacing the sensor is easy, and most of the time, it can be done on the field.

If you’re uncomfortable with replacing the sensor, send it to the nearest calibration and service center or call the manufacturer’s technical support; they can help you.

Data Logging

This is not categorized as a maintenance routine, but in my experience, keeping your unit’s data logs in a place where they can be accessed is a good idea.

Make a habit of downloading data logs from your gas detector once or twice yearly and save that information in a secure location.

This will help you and your company in case of an accident and the authorities or insurance companies want to investigate what happened. Those data logs might save your job.

What accessories come with portable gas detectors?

Depending on the manufacturer and your need, you might need some or all of the accessories below, and I grouped them according to how you can use them.

Accessories for comfortability

These accessories will make you comfortable when using a portable gas detector.

Neck traps

These are the traps that will help you to wear your portable gas detector on your neck.

Hard hat clips

These are the clips that will help you to wear your portable gas detector with your hat.

Body Harnesses

These harnesses will help you wear the portable gas detector to the chest or other body areas.

Accessories for device protection

Here are some accessories that will protect your portable gas detection.

Concussion-proof boot

This rubber boot will protect your portable gas detector if it falls under hard material.

Carrying holster

This holster can carry a gas portable detector and most accessories, such as sampling hoses and a calibration cap.

Vehicle attachment

This accessory will hold your portable gas detector if you want to charge it using your vehicle.

Accessories for protection against water and dust

These accessories will protect your portable gas detector against water and dust.

Sensor protection filters

These are the filters ( hydrophobic and particulate) that will protect your portable gas detector against water( hydrophobic filters) and dust ( particulate filters). They are very useful in moist and humid environments.

Water floatation aid

This accessory will protect your portable gas detector when using it for gas detection in an environment where you need to submerge the detector underwater.

Accessories for sampling

If you use your gas detector in sampling mode, here are some accessories you might need.

Manual hand aspirator

If your portable gas detector does not have a built-in motorized sampling pump, you will need a manual hand aspirator; ask your manufacturer which one is compatible with your detector.

Sampling Probe and flow tubing

The portable gas detector will need a sampling probe and tubing to draw an air sample.

Test cap

A test cap ( usually black) is a small cap that will help direct the air sample to the sensors.

Pump module

Some portable gas detectors will need a pump module for sampling, a device that fits over the unit sensors and allows air to be drawn.

Give a call to your portable gas detector manufacturer to find out which of these accessories you need for sampling.

Accessories for power and charging

Here is a list of some accessories for power and charging power.

Various battery options

Most manufacturers offer different types of batteries, including alkaline and lithium batteries.

Recheargable batteries

Most manufacturers offer the option of choosing between rechargeable and non-rechargeable batteries; choose one that suits your application.

Vehicle charging adapters

Most manufacturers will offer you that option if you want to charge your portable gas detectors using your vehicle.

Cradles and accompanying chargers

Most manufacturers will offer charging cradles and wall chargers. If that is your case, ask for them.

Also, you need to ensure they give you a wall charger plug you can use in your location. (Wall plugs for Europe differ from those used in the USA.)

Portable gas detector calibration frequency

Each manufacturer will recommend the frequency you should calibrate their instrument, from once per 30 days to once per year. I will recommend calibrating your unit at least twice per year.