Fixed vs. Portable Gas Detectors: What Is the Difference?

With over five years of experience in the gas detection industry, I often receive the following question: When is a portable gas detection system preferable to a fixed one?

In this post, I will compare Fixed and portable gas detectors, explain their differences and similarities, and provide practical guidance on what you need to consider when selecting the right gas detection system for your project.

Fixed vs. Portable Gas Detectors: What Is the Difference?

The main difference between fixed and portable gas detectors is that fixed detectors are fixed in one location.

In comparison, portable detectors are personal protective equipment you can wear and move from one location to another.

I will share a table summarizing the differences between the two types of gas detectors.

Table 1: Fixed vs. Portable gas detectors

Portable Gas Detectors  Fixed Gas Detectors
Assigned to workers as Personal Protective Equipment. Permanently installed in a specified area.
They are ideal for small areas. Are suitable for large area
They need to be turned on, warmed and charged The detection is continuously no need for warmup ( only for the first time)
The warm-up is required before use No warm-up is required 
It is recommended that bump test portable gas detectors every day before use. It is recommended to bump-test fixed gas detectors every 30 days.
Where the worker goes, the unit goes It will stay in one location
Short life span (1 to 3 years) Usually have longer life span ( 4 to 7 years)
Usually have LED and Audible alarms They usually have outputs such as relays, 4-20mA, Modbus, Fieldbus, etc.


Similarities between fixed and portable gas detectors

The main similarity between fixed and portable gas detectors is that both detectors use the same technologies.

The most common gas sensors are the Catalytic bead, Infrared, VOC, and electrochemical sensors.

Here are the most common sensors used in gas detection.

Fixed vs. Portable gas detectors: considerations where choosing the right gas detection system

Here are a few considerations you need to know before you decide if you need fixed or portable gas detection equipment.

Physical area to be monitored

The area to be monitored matters. If it is an area where people will be there most of the time, like a kitchen, battery charging area, or garage, it makes sense to have a fixed gas detection system.

But if it is an area where people can go and get out as quickly as possible, like a confined space, it makes sense to have portable gas detectors.

Types of gases to be monitored

For example, most VOC gas detectors are portable, and most nitrogen dioxide gas detectors are fixed. You can pick one or the other depending on the gases you want to monitor.

Hazard is permanent or transitory.

You can pick one depending on the type of hazard. It is best to go with the fixed permanent gas detection system for permanent hazards, but if the hazard is transitory, portable gas detectors make sense.

Level of risk to workers

Depending on the risk of gas leaks to workers, you can choose one of the two types. If the risk is very high, I recommend that each worker wear a gas detector. This will alert them immediately when there is a risk.

Sometimes, it is better to have both fixed and portable gas detectors.

The fixed gas detection system will alert them before entering the premises, and the portable system will alert them.

Compatibility with other systems

Sometimes, you already have a system in place. For example, you have a fire detection system and want to integrate the gas detection system.

Usually, portable gas detectors can not be wired or integrated into control panels, DCS (Distributed Control System ), PLC (Programmable Logic Controller), SCADA (supervisory control and data acquisition), BMS (Building Management System), etc.

In this case, you will need fixed gas detectors that can be integrated into those systems.

Key Takeaway: Fixed vs. Portable Gas Detectors

Fixed Gas Detectors are ideal for continuously monitoring specific areas or zones within facilities where gas hazards exist.

Portable Gas Detectors are suitable for applications requiring mobility, such as confined space entry, leak detection, maintenance activities, or outdoor monitoring.

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