How do you safely fill a gas can before filling up your boat?

When a fluid encounters a solid, an electrification of the solid is created, due to the phenomenon of electric double layer. This charge may be sufficient for a container insulated from earth to initiate a spark. Imagine this happening on a jerry can that you fill with super.

Olivier Tourchon Published on February 12, 2021

When we fill up our boats with fuel (petrol, not diesel!), we sometimes use jerrycans to transport the fuel from the petrol station to the harbour. We know the basic precautions to avoid a disaster: no lit cigarettes, no mobile phone in use and no visible source of ignition (ignition). But have you thought about dielectric physics? We forget it all too easily when we fill up our petrol cans.

Creating an electrical charge

The principle is elementary. When a fluid meets and flows in contact with a solid, an electric charge is created at the point of contact between these two elements. This is known as flow electrification.

Illustration du principe d'Ã©lectrisation par l'Ã©coulement — Illustration of the flow electrification principle

The figure above illustrates this phenomenon. In the upper left corner, the pump gun is grounded. Bottom right, the jerry can with the fluid (petrol in our case) in "neutral".

Risk of electric arcing during creation

As the path of the electricity leakage is always the shortest, it will use the dispensing gun to reach the ground. It is therefore precisely when the operator approaches the dispensing gun to the jerrycan that an electric arc, a spark, can occur. To avoid it, it is imperative that the jerrycan be placed on the ground.

Let's add that in our case, the fluid involved is gasoline, Super. It has the peculiarity of being easily flammable and its vapours are explosive. As we sail more often in the summer, we usually fill up these jerrycans when the weather is nice and hot, increasing the volatility of the gasoline.

Precautions of use to be respected

Here are the precautions to take when filling your jerry can at the gas station:

Remplir les jerrycan, avec prÃ©caution — Fill the jerry cans, carefully

Never use a metal jerry can
Place the canister(s) on the ground (not in the trunk of the car where gasoline vapours will accumulate)
Keep the cans away from each other
Use canisters according to EN13341 standard
Limit the quantity transported to a maximum of 60 litres
Touching a metal surface before handling the dispensing gun
Place the jerrycans on the ground, on the cement of the petrol station directly (without cardboard, wood, tarpaulin ... on the ground)
Immediately alert station personnel of even the slightest spill on the ground
Avoid filling the jerry cans when it is very hot