The Basics of Explosion Protection

As if toxic gases and fire hazards weren’t enough, many environments also have to monitor for explosion risks. Discover how an explosion occurs and how you can protect your workplace against it.

Fundamentals of an Explosion

For an explosion to occur, there are events that all must happen at the same time.

• An ignition source, to initiate the explosion.
• A sufficient concentration (Between the upper and lower explosion limit, LEL & UEL) of a flammable substance in the atmosphere.
• A sufficient degree of dispersion or scattering.

To avoid an explosion, you need to work towards removing one or more of these factors.

Protecting Against an Explosion

To mitigate the risk of an explosion, there are a number of measures you can take. For example, you can remove or reduce the amount of explosive mixture that is present or released into the atmosphere.

Sources of ignition are removed from the environment or carefully protected, or, if all else fails, measures should be taken to reduce the impact that an explosion would have.

Primary Explosion Protection

Explosion protection can be split into two forms; primary and secondary. Primary explosion protection refers to avoiding an explosive atmosphere from forming. This involves:

• Removing combustible liquids and gases from the atmosphere.
• Increasing the LEL of an atmosphere.
• Limiting the concentration of explosive substances in the atmosphere.
• Increasing ventilation through airflow systems or large openings to the external atmosphere.
• Using an emergency stop function as part of concentration monitoring.

Secondary Explosion Protection

Secondary explosion protection refers to preventing the ignition of an explosive atmosphere. These measures include:

• Removing the ignition source
• Using intrinsically safe equipment
• Ensuring any ignition source is housed in a flameproof enclosure.

Removing an Ignition Source

To be able to remove or protect it, you must first identify it. Below are some common ignition sources that could be present in your environment:

• Hot surfaces such as heating pipes or hot equipment.

• Naked flames.

• Mechanical sparks through friction, strokes, abrasion.

• Electrical sparks.

• Compensation currents.

• Static electricity and electrical fields through radio waves.

• Lightning and ultrasonic sound.

• Optical ignition sources.

Being able to identify and control the factors contributing to an explosion is the only way to safely avoid explosions in your working environment. For more information on monitoring concentrations of combustible gases and how DSA Suppliers can help you, get in touch with us for expert, no-obligation advice.