Rule 236
You MUST NOT use front or rear fog lights unless visibility is seriously reduced (see Rule 226 ) as they dazzle other road users and can obscure your brake lights. You MUST switch them off when visibility improves. Law RVLR regs 25 & 27
SteerTogether · Official English reference
Read rule 236
Adverse weather: rules 226–237
Review how wet roads, ice, snow, wind, fog and heat affect visibility, grip and safe driving decisions.
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