I swear my girls start the day by venturing out of the coop and pooping on the ramp. I start my day with a cup of coffee. They start their day with a nice juicy poop on the ramp. And some of the places they can get poop is, quite frankly, impressive. How did it get on the walls? Anyway, I wanted to use something that doesn't cause fumes and irritate tender nasal passages. I've heard their respiratory systems are fragile in some ways as are mine. But still, I needed something that will kill bacteria, viruses, fungi, and mites. Enter: Bar Keeper's Friend It's cheap. We're talking $2.50 for a can taller than a 20oz coke which goes a long way. It's a powerful stain lifter that I've used in my kitchen and on my glass stove top for a number of years. I like that I don't feel fumes displacing oxygen in my lungs that send me running from the room. I don't sneeze or cough and my eyes don't burn while using it and it's better at lifting crud. I'm sensitive. I've used it in places where oven cleaner didn't work. It can clean rust off of metal! The active ingredient is Oxalic Acid. Acid is a scary word, but trust me--no need to imagine your face melting off as you use it. You've run into it before without knowing. It exists naturally in spinach, strawberries, tea, beet root, lemon and lime peels, okra, chocolate, peanuts, pecans, etc. So obviously, small doses are fine. It's also used as a "non-chlorine bleach". You don't want to eat a high dose. Rhubarb leaves contain a high dose which is why you don't eat them. But it is safe to use. Studies show that Oxalic Acid is a good product to control varroa mites in beehives. We all know how sensitive bees are. While potent, this powder form is very easy to work with. Wear gloves if you wish (just as you would with bleach) because you can absorb it through your skin. But as long as you don't consciously draw the powder up your nose, you won't inhale it, nor will your chickens. Mixing the powder form into water won't create fumes. Honestly, it's so diluted when I use it that I don't wear gloves. It's not a flighty powder either, nothing like Diatomaceous earth. You sprinkle it out of the can and it just plops down. My coop is small. I used a small amount (less than a tablespoon) with about a cup of water. With a scrubbie, I dipped it in the solution and made a speedy single pass over the poo, mostly to knock down the large pieces of poo. This spreads the cleaner over the "concrete" chicken poo seems to form to stick to surfaces. Your life is made easier by giving it a minute or two to work. By the time I completed my single pass, the second pass removed the stuck on poo without much scrubbing (aka-cramps or twinges in my shoulders or back). Then I rinsed with water. No fumes, no coughing, no sneezing, no watery burning eyes, no running for oxygen. Anyway, I thought I'd pass this along. Hope it helps!