Explosion Protection for Fuel Dispensers: The Basics to Know Before Ordering

When overseas customers ask us about fuel dispensers, one question comes up again and again: “How is explosion protection handled?” Here are the basics worth knowing before you place an order.

1. Why a fuel dispenser needs explosion protection

Gasoline gives off vapour even at normal temperatures, and mixed with air it ignites easily. A dispenser contains motors and electrical parts, so it is designed with explosion protection in mind to make sure none of them can become a source of ignition through sparks or heat.

2. What hazardous zones are

Areas are divided into zones by how likely a flammable atmosphere is to be present. In general there are three:

Zone 0: a flammable atmosphere is present continuously or for long periods
Zone 1: a flammable atmosphere is likely to occur during normal operation
Zone 2: a flammable atmosphere is not likely during normal operation and, if it occurs, lasts only a short time

Which zone applies around a dispenser, and how far it extends, depends on the standards and regulations of each country or region.

3. Common protection types

Flameproof (Ex d): the enclosure withstands an internal explosion and keeps the flame from reaching the outside. It is commonly used for motors.
Intrinsic safety (Ex i): the energy in a circuit is kept so low that it cannot ignite a flammable atmosphere. It suits low-power circuits such as sensors and displays.
Increased safety (Ex e): insulation, terminals and similar parts are strengthened so they do not produce sparks or excessive heat in normal operation.

Which type is used depends on the component and the installation conditions, and they are often combined.

4. How to read certification and nameplates

IECEx is an international certification scheme and ATEX applies in Europe. Some countries also require their own local certification. On a nameplate or certificate, look for:

The protection type (Ex d, Ex i and so on)
The gas or vapour group (gasoline is generally classified as IIA)
The temperature class (T1 to T6; gasoline is generally T3)
The certification body and the certificate number

5. Rules differ by country and region

Explosion-protection rules and the certification you need vary by country, region and site. Before a project goes ahead, it is important to confirm the local regulations and the requirements of the owner or main contractor.