To add to the examples given by the other answerers, 'blow out' can also be used to refer to doing something, particularly eating, to excess on one occasion. 'I had a real blow out at the buffet restaurant last night, now I have stomach ache.'

If you are driving your car and a tire suffers a sudden loss of integrity, then you can say you had a 'blow out.'

No, “blow out” has other uses. Examples: 1. The tire blew out on my car (meaning, the tire suddenly lost all of its air). 2. The game was a total blow out, or “We totally blew them out” (meaning, one team badly beat the other team).

We use "Switch off" for electronics, such as lights, computers, TVs that use a "switch". A fire isn't electronic, so it can't be switched off. Unless, it is one of those fake fireplaces that has a switch on the wall :) The word to understand most importantly is the first word. "Blow." If you look up "Blow" and understand what this action is, and how it works, it will make sense how it can be used for a fire. It also can be used in some set phrases, such as "blown out of proportion", which means that something became a bigger idea or problem than it needed to be. Had too big of a reaction to something.

I would also like to add: Blow out also can apply to hair styling using a blow dryer: "I'm going to the hair salon to get a blow out." A "blowout" is a party! You can have a blowout for your birthday, but we usually use this to describe big parties with lots of people and activities :)