Goodguide separates ingredients into two categories — “ingredients of health concern” and “controversial ingredients.” only the former contribute to a product’s rating. Understand all the ins and outs of isas, including how much you can save and what restrictions they have. Of your new worcester boiler install a new worcester boiler for as little as £ a month*. Still have a question? ask your own! New regulations were introduced in to govern uk boiler installations. Learn what you can do.