A well chosen Air Purifier will filter out everything from basic allergens to tobacco smoke , viruses and even chemical VOC's ( volatile organic compounds - ie. the glue found in many new carpets etc).
However, different units work better on different issues, for instance one purifier might be the best in the world for destroying viruses, but be fairly ineffective against tobacco smoke. Another may offer fantastic respite for asthma sufferers, but be virtually negligent in the removal of odours.
We answer all those queries and more in our air purifiers guide below. But of course you can always just pick up the phone and ask the question if you want to get it right in double quick time!