This rule/law about getting chimneys swept annually or even (some communes) bi-annually.
Does this apply to all chimneys that are in use? We have two chimneys - one is from our oil boiler and the other is from our hob.
As far as the hob chimney is concerned, we don’t know the 20+ year history before we moved in. I can see, by taking off the filter, that the fan motors are very greasy.
The chimney out of the back of the oil boiler is ~20cm dia. corrugated stainless pipe for a metre, vanishing into the brick chimney up through the roof. There is some heath robinson arrangement with a tin can hanging off the stainless chimney.
It’s specifically wood/solid fuel fires/stoves. Moving on to your other chimney in the kitchen, well worth having it done as they do catch fire from all the congealed grease etc. A restaurant on an estate I looked after had one from the kitchen that had not been cleaned as access was difficult, it caught fire, fortunately no real damage but a lot of embarrassment from the duct work cleaning company who had to pay for their negligence, so best give it a treat and clean it IMO.