Instruction: Extract information from the supporting document to answer the given question.

Input:
Question: what is the CFM for this microwave?
Document: We bought this microwave/convection oven for use in our motor home. It fit perfectly in the opening which was a plus. And, it works perfectly which we found out on our last camping venture. I would recommend the R-188OLS for any over the range usage.
The touch panel is designed better, as well as the door. The door in my old microwave was developing cracks. I felt that it must be a pretty good design, being that it virtually had not changed that much in 10 years. The changes that were made, seem to be for the better.
This was such a good price for this particular item. I've compared the price online, and Amazon sold for by far the lowest price. Not to mention that there was no tax and no shipping fee.The reason with 4 stars and not 5 is that power of this microwave is not that high. I had one from Panasonic with 1200 watt, and that was very nice until blew up after 7 years of hard work.
I don't think there is much more I could expect from a microwave. I have had this product installed for a while and find it makes cooking tasks so much easier.I'm not the pro chef and it makes tasks such as defrosting so simple. No guessing how long, what power, or when to break apart,etc. With my old microwave, I would always seem to wind up with larger chunks of cooked meat.
I've tested with some toffee cookies. Ones from my range/oven came out more moist inside and crisp outside. The convection oven dried the cookies, and they came out a bit too hard. Since I had only one oven before I bought this product, it is nice to have the second oven for the holiday seasons.My old microwave was on the counter, and now I have so much more counter space. That's the part I love most of all.
This is an excellent convection microwave combo. Perfect for use instead of a conventional oven for a small family or for those times that a second oven is needed & as a microwave, too. The installation instructions were almost nonexistent but once installed it's been great! So many features, such as Sensor Heating & Sensor Cooking in the microwave mode. The convection oven has both preprogrammed times & temps with "compu" settings or you can enter your own. I would definitely recommend this oven.
I purchased this microwave as a replacement for my previous Sharp microwave. I had the previous one for about 10 years. It finally died. I felt the first one worked so well, that I would get a new Sharp to replace it. It turned out that the new oven was an exact replacement for my old oven. I was able to use the existing mounting plate in the back, as well as the holes lining up perfectly to bolt down from the top.
Amazon had the best price for this oven and it sure is nice. It says it is 850 Watts but it seems to cook better than other ovens I have had over 1000 watts. It is sleek, quiet and good looking. Installation was easy. I was able to retrofit it to the old unit by another manufacturer. Having the convection oven is a nice convenience although I rarely use it, opting for the microwave.The unit I received was obviously a return unit that had been opened.
I needed to replace my older Sharp Microwave/Convection oven that had stopped microwaving after 8+ years and looked and compared all other brands and models both online and in the big retail stores. Many don't display the Sharp brand, and I really like to physically see an item before I purchase it. I had been very satisfied with my 2 previous Sharp microwaves that gave me many years of repair-free service and I also like the push-button feature.
I purchased this microwave/convection oven less than two years ago for my family's use. This consists of two people who work full time & the appliance was mainly used to do some baking and heat food, on occasion. A month ago the button broke. Sharp has no buttons in the United States to repair this appliance. The Sharp people in customer service never took notes so every time I called to try to find a new parts business, it was like the first time. Don't buy this appliance.
Answer: I do not see an airflow rating in the manual.  I mounted it 18.5 inches above the cooking surface with a straight out (horizontal) vent to outside the house and it does an excellent job of removing cooking smoke/odors (as tested by my daughter burning breakfast sausage) even on low speed.  I would conservatively estimate the air removal to be at least 250 cfm on low speed and over 400 cfm on high.  For reference I work in navy propulsion plants and have to verify airflow of various intake and exhaust air systems for periodic maintenance so my estimates should be reasonably accurate.  As a side note, on low the noise of the fan is barely noticeable, on high it is slightly louder than calm conversation.  Hope this helps.