Firefighters are warning the public about the potential dangers posed by e-cigarettes, after revealing they have tackled a dozen fires involving the devices in the last three years.

South Yorkshire Fire & Rescue says until 2013 it hadn’t attended a single incident caused by e-cigs, but the number of fires involving vaping equipment has climbed ever since.

E-cigarettes are commonly charged via a computer USB port. Fire investigators think fires commonly start because the e-cigarette is left to charge too long, they are charged on or close to soft furnishings, or because the charger itself is faulty.

Head of community safety Trevor Bernard, said: “Fires caused by e-cigarettes are an emerging trend which a few years ago simply did not exist. Whilst e-cigs may offer a safer alternative to traditional cigarettes, they are so popular now we do need to make sure people know how charge them safely.

“The advice for e-cigs is really the same as for many smaller electrical appliances like mobile phones and laptops- don’t be tempted to buy cheap unbranded chargers, don’t leave them to charge whilst you are out of the house or asleep and keep them well away from flammable materials.”

Tips to prevent e-cigarette fires include:

• charge the device on a flat, solid and stable surface, such as a kitchen worktop
• keep the device away from flammable or combustible materials when charging
• never leave the device on a bed or close to soft furnishings, or in a cluttered space
• don’t exceed the recommended charging time, or leave unattended for any significant length of time

Fire officers say that whilst nearly every type of fire has reduced significantly during the last decade, thanks to safety visits and better awareness of risks, electrical incidents have stubbornly refused to drop.

Electricity is involved in about two thirds of all accidental house fires, with household appliances the most common culprits.

As part of a major campaign to reduce electrical fires, officers are encouraging people to check the safety of their home electrics by completing a short, online checklist at 13orbust.co.uk