Is a flash of electricity behind a light switch dangerous?

In one of our rooms when I turn on the light the gap between the actual switch and the outer bit of the switch flashes blue with electrcity (especially good to see at night). No sparks come out the switch. Now Ive seen this a lot with light switches in my 33 years of switching lights on and off and assumed it was normal and just part of the power going through the system. But hubby tells me today that its probably v dangerous

Is it dangerous? How dangerous? Why does it happen and can it be fixed?

This topic has been covered a few times before. It is quite normal, as long as we're not talking a massive amount of arc'ing. The only time it could be dangerous is if you had a major gas build up.

This is normal on high power switches when switching on or off under load. However on a light switch i would say the mechanism is getting weak and for piece of mind i would just change the switch .

Nick

Also the switch contacts wear / build up carbon deposits that cause arcing through poor contact. Just change the switch if you are worried