You may already know how to remove the streak of red wine within your home, But what about other messes that are harder to clean up? The smell that you can’t eliminate or the quantity that your kid or pet caused… that’s the ones that won’t disappear with a quick swipe of a Mr. Clean Magic Eraser.

The most difficult spots originate from a biological source, so we sought the help of a professional: Gabrielle Martin, a Crime scene cleaner and director for Bio Recovery.

Here’s what Martin says about removing the most challenging marks from your home.

Blood

Some cuts happen, and often, they’re not noticed and can result in the possibility of tracing blood around your home due to something you’ve stepped on. (I’m looking at you, metal potholder looms.) If it’s nothing major and still in good condition, you should be able to remove it quickly. However, when it’s sitting, that can create a problem.

“At a molecular level, blood has the tendency to bind to any porous materials or fabric,” Martin states. “If there’s a small amount of blood on a piece of clothing, you’ll be able remove it by rubbing the area using hydrogen peroxide as well as cold water. It’ll need some manual and physical effort to get rid of the stain, and based upon the depth of stain it might not come out.”

Try to tackle it as quickly as possible, or else you’ll spend the night catching another chance to get your arms whipped.

Urine

Many companies manufacture enzyme-based cleaners to eliminate urine from fabric, but what happens if your pet or baby is injured and you don’t own one of these cleaners? Don’t panic. Just three things to eliminate fresh urine staining: water, dish soap, and white vinegar.

“Urine is difficult due to its low solubility,” Martin states. “Household cleaners do not easily break it down.” Therefore, instead, try a traditional homemade solution. Mix two parts of water with one teaspoon of dishwashing soap with vinegar. Sponge it all around and into the stain (after wiping up any urine), and then apply a dab of water to the cloth to wash. It is dried by blowing the liquid using a dry, clean cloth.

Feces

In the case of staining left over from feces, Martin says it’s not that big of an issue as long you’re quick cleaning up. “Poop stains only make this list if they’ve been left for some time,” Martin states. “When removed immediately, they’re much more water-soluble and less likely to create a residue. When it’s dried, it becomes harder to eliminate, as the feces are already absorbed into the material’s fibers. This means it’s an extended process to cleanse. Sometimes, it’s difficult to get entirely out.”

If you find the stain has been sitting on the fabric for an extended period, you should remove the color from whatever the item is and purchase another one. For things such as dirty underwear or a common household blunder, soak it in baking soda and scrub the area using a brush.

Foul Smells

Have you ever walked into your home to find an unmistakable scent in your house? It’s possible to identify the source. However, the cause could be an unanswerable question. As Martin states, to eliminate the smell, you must determine the source.

“For simple smells in the home, it’s important to know buying fragrances and deodorizer sprays aren’t going to fully treat the problem,” she states. “If there’s an odor it’s coming from somewhere and the most effective way to get rid of it is identifying the source and getting rid of it at the source of the problem. It may take some effort however, if you wish for the smell to go completely, it needs to be taken care of.”