Can I clean this mold myself? A six-question check
Most people who find mold want one answer before anything else: is this a sponge-and-gloves job for Saturday, or do I need to bring someone in? Federal guidance gives a fairly clear way to decide. The EPA starts with how big the patch is, then lists a handful of situations that change the answer no matter how small it looks. CDC adds who should stay out of the cleanup entirely. This page turns that guidance into six questions. Nothing is collected or sent anywhere; the answer appears on this page as you go.
How the checker decides
| If this is true | The answer | Where it comes from |
|---|---|---|
| Sewage, a backed-up drain or outside floodwater caused it | Professional with contaminated-water experience | EPA, Mold Cleanup in Your Home |
| Mold may be in the ducts, at an intake, or the AC is part of the moisture problem | Stop running the system; professional. Wet or moldy duct insulation gets replaced | EPA; EPA on air duct cleaning |
| About 10 to 100 square feet | Professional; work area sealed off with one layer of plastic | EPA remediation guide, ch. 3 |
| More than 100 square feet | Professional; full containment | EPA remediation guide, ch. 3 |
| A lot of water damage, even if little mold shows | Treat it like a large job | EPA |
| The leak or humidity isn't fixed | Fix the water before any cleaning | EPA Brief Guide to Mold |
| The cleaner has allergies, asthma, COPD, lung disease or immune suppression | Someone else cleans | CDC, Mold Cleanup |
| None of the above, under about 10 square feet | Usually fine to do yourself | EPA |
Why 10 square feet is the line
EPA describes the do-it-yourself size as less than about 10 square feet, which it pictures as roughly a three-by-three-foot patch. That size isn't magic. It's the point where the amount of spore-laden dust you stir up while scrubbing gets large enough that the rest of the house needs protecting. Past it, EPA's remediation guide moves from "clean it carefully" to sealing the work area behind polyethylene sheeting, and past 100 square feet to a double layer with fans pulling air out of the space. Those are steps most homeowners don't have the equipment for, which is why the checker sends anything 10 square feet and up to a contractor.
Measure generously. Add every patch in the room together, include the stained area around the visible spots, and remember that what shows on the paint side of drywall is often the small end of what's on the back. If you have to cut into a wall to find out, EPA warns that disturbing a hidden colony can release a lot of spores at once.
What "the water came from" means around Oklahoma City
Here the question usually comes down to a few familiar sources. A hail-damaged roof or a slow drip at the kitchen sink counts as clean water, though it can still feed a big problem; see hail, roof leaks and attic mold. Water that ran across a yard during a spring downpour and came under the door, or anything that backed up through a floor drain or toilet, counts as contaminated even if it looked clear. Our flood page walks through the first two days after that kind of event. Sweating ductwork and overflowing AC drain pans in July are a heating-and-air question, which is why question 3 matters so much here; the summer humidity guide explains why OKC attics and air handlers get wet.
If the answer is "do it yourself"
- Gear up. CDC calls for at least an N95 respirator, gloves made of nitrile, vinyl or rubber, and goggles that seal out dust. Vented safety glasses don't count.
- Scrub hard surfaces such as tile, glass, metal and sealed wood with detergent and water, then dry them completely. EPA doesn't recommend bleach as a routine step. If you use it anyway, CDC's limit is one cup per gallon of water, with fresh air coming in, and never mixed with ammonia or another cleaner.
- Bag what won't come clean. EPA notes that absorbent materials like ceiling tiles and carpet may have to be thrown out, because mold grows into them.
- Don't paint over it. EPA says paint or caulk on a moldy surface just hides the problem and peels.
- Watch the spot. If it returns within weeks, the moisture wasn't really fixed. Run the checker again with question 4 answered "no".
About these sources
Every rule above comes from the U.S. Environmental Protection Agency's Mold Cleanup in Your Home, its Brief Guide to Mold, Moisture and Your Home, chapter 3 of its Mold Remediation in Schools and Commercial Buildings guide, its page on air duct cleaning, and the CDC's mold cleanup safety page, all read October 2026. Oklahoma has no state mold standard of its own; the State Department of Health says it has no authority over mold complaints (OSDH), so the federal guidance is the yardstick here. The checker is a general guide, not an inspection of your home.
Questions people ask
- Is 10 square feet of mold a lot?
- It is EPA's rough cutoff for a homeowner cleanup, about a three-by-three-foot patch. Below it, most people can clean it themselves if the water is fixed and nobody doing the work has a health condition that mold aggravates.
- Can I clean mold in my air ducts myself?
- EPA advises against running a system you suspect is contaminated and points owners to its duct-cleaning guidance. Duct insulation that got wet or moldy can't be cleaned effectively and needs to be removed and replaced, which is contractor work.
- Can teachers, realtors or neighborhood groups link to this checker?
- Yes. It's free, it asks for no contact details, and the rules it uses are listed on the page with links to the EPA and CDC pages behind them.
Talk to a mold contractor in the OKC metro
This line is run by an independent referral service, not a mold company. Your call or request goes to a local contractor who quotes and bills you directly. Water still coming in? Shut it off or catch it first, then call.