Fire officers who have seen a rise in reported incidents caused by e-cigarettes have issued advice on how to use the cigarette replacements safely.
The guidance includes not leaving e-cigarettes on charge overnight and only using the parts that come with the device.
Users have also been urged not to use them in the same area as home oxygen cylinders.
The Chief Fire Officers Association has issued the following advice for users of e-cigarettes to follow when charging them:
- Always use the correct charger and follow the manufacturer's instructions
- Never charge a battery that has signs of damage, that has been dropped, or has been subjected to impact
- Never plug a charger into a non-approved mains power transformer
- Check that your e-cigarette battery has overcharge or overheat protection
- Remove the battery from charge when complete - don't over charge
- Never leave a battery on charge unattended
- Don't use if wet or exposed to water
- Do not over tighten the atomiser or when connecting to charger
- Ensure that you dispose of batteries correctly.
Merseyside fire and rescue service area manager Myles Platt said: "We urge people to always use electrical equipment in accordance with the manufacturer's instructions and guidance, always ensure that no electrical items are left charging overnight or left unattended for a long period when being charged and do not mix parts from different e-cigarettes.
"Only use the original charger or electrical cables supplied and ensure you purchase electrical items from a reputable source.
"Finally, and most importantly, please ensure you have working smoke alarms on each level of your home and test them regularly - smoke alarms save lives."