The law in relation to the use of front fog lamps is very clear and is contained within the Road Vehicles Lighting Regulations 1989
They state that, when in use, they must not cause 'Undue Dazzle' or 'Discomfort' to other persons using the road. In addition, they must only be lit in conditions of 'Seriously Reduced Visibility'.
Unfortunately, front fog lamps are used at times as a fashion accessory. The danger arises when they are used in clear conditions and the intensity of the light causes other drivers/road users to be dazzled. This results in momentary blindness until the driver is able to re-adjust and focus on the road ahead. My advice would simply be, to be courteous to other road users and use the fog lights only when necessary.
Found this on a site, this has come from a current serving Police Officer
Unfortunatly no information on the penalties, will look into it further
Hope this helps