The older model Trustfire chargers don't have the switch the newer models do.
I've taken one apart here and inside it all looks fine.
that picture has done the rounds already.
We don't know what caused the battery that it was charging to vent. We don't know what battery it was and whether the battery was fake/faulty/wrong type. We don't know what power cable was used to plug the charger into the mains or what voltage it was running at (using a travel adaptor with no fuse in it an an EU/US cable into UK mains voltage is asking for trouble if there is a power spike.
It could have been user error, it could have been a faulty/fake charger, it could have been a battery issue and not a charger issue.
Putting up a pic of a burnt out TF001 is just scaremongering. (incidentally the charger in that picture is one of the older model versions that doesn't have the switch on the side)
When you are charging ANY lithium batteries (including your mobile phone) you should:
NEVER charge unattended or overnight
ALWAYS charge the correct battery using the correct/supplied cables
NEVER use an unfused cheap nasty travel adapter to plug anything into a UK 250v mains source using a EU/US 110v cable
IDEALLY charge these batteries inside a charging bag.