Instruction: Generate an answer to the question by utilizing the information contained in the document.

Input:
Question: size room? what size room this is for?
Document: I ordered this overnight and plugged it in immediately when it arrived the next day and felt better within a few hours. It was nice to actually feel the air in the room change so quickly. It blows out cold air, so be warned you may need to turn up your heat on a cold day with this unit on High. It's a nice design, not too intrusive as far as the size of it, and doesn't make too much noise while it's on.
Worth every dime!!! This is the second one I have ordered. Purchased one about two months ago run it 24/7 haven't had to change the filter yet (occasional cleaning of pre-filter due to having cats, very easy though and saves main filter). Noticeable difference within an hour or two (depending on the size of the room). Not very loud, but does give a nice ambient noise while sleeping I think.
Also, AHAM (Association of Home Appliance Manufacturers) has tested and assigned CADR's (Clean Air Delivery Rating) of 49 dust, 39 pollen, 39 tobacco resulting in a max recommended room size of 60 sq feet (6x10 walk in closet!) for this air purifier.Just Google "CADR" to find the truth (since apparently I'm not allowed to post outside links).I wish I had known all this before I bought this WH10200.
the top is a flat surface, and the manual is the perfect size, so it works perfectly.
Hoover air purifier works very nicely. Thought it would be a bit bigger but works very nice regardless of size, for my little apartment. Thank you for being prompt with sending. =)
After running all night long at low setting, we were both convinced that the unit is indeed remarkable. Two days leter, we are still impressed.The size and appearance of the unit are very appropriate.ODOR REMOVAL:There are few offensive odors in this house (no kids, no smokers, no pets, two adults).
I have two of these units now. The versatility of being able to turn on and off different features such as ION and UV, plus the timer option and three fan speeds, plus he compact size makes this unit perfect for my children's bedrooms. It has helped me get their allergies under control in this land of heavy spring pollen.
I was having some terrible allergy problems, and after I started using this, my allergies improved. I can't prove it, but I believe the filter has really helped. The size and design are great. I like to sleep with white noise, and the filter provides that as well. As some other people mentioned, the lights are a bit bright, but I cover them up at night, which solves the problem easily.
Odors such as coffee brewing, cooking fish or broccoli remain. I hoped this unit would do better based on the reviews. It is not as noisy as larger units I have tried (which performed about the same) and I appreciate the air circulation it accomplishes for it's size. It does not blow air out of the entire front but only blows to the right side!? It doesn't have an energy star rating so we'll see if it noticeably increases electricity use.
I leave mine on medium almost all the time. I never shut it off unless I'm cleaning it. I plan on taking it with me in my motor home this year. Its size is perfect for traveling.I purchases a replacement filter with it when I bought it. I've had it 2 months and have cleaned the pre-filter about 4 times. Easy as can be. It does help to use a vacuum on the paper filter inside past the pre-filter.
Answer: My question exactly!  Amazon should include approx. Sq. footage coverage in the product description. I was thinking of getting one for upstairs and one for downstairs.  Think I will try it though.