Cleaning a blood spill requires more than wiping it up with a paper towel. Blood can carry dangerous pathogens, including hepatitis B and HIV, which survive on dry surfaces for over a week. The right approach protects you from infection while fully decontaminating the area, and the process differs depending on the size of the spill and the type of surface.
Why Blood Spills Need Special Handling
Blood is classified as a biohazard because it can transmit serious infections. Hepatitis B, hepatitis C, and HIV can all persist on surfaces for seven days or longer, even after the blood has dried. You can’t tell by looking at blood whether it carries a pathogen, so every spill should be treated as potentially infectious regardless of whose blood it is or how small the spill appears.
The main risk during cleanup is contact between the blood and any break in your skin, or with your eyes, nose, or mouth. Scrubbing dried blood can also generate tiny airborne particles called aerosols, which is why the cleanup method matters as much as the disinfectant you choose.
Protective Gear You Need Before Starting
Put on protection before you touch anything. At minimum, you need:
- Disposable gloves: Nitrile or latex examination gloves work well. If a glove tears or gets punctured, stop and replace it immediately. Never wash and reuse disposable gloves.
- Eye protection: Goggles or glasses with side shields. A face shield is even better for larger spills where splashing is possible.
- A mask: Especially important for dried blood, where scraping or wiping can release particles into the air.
- A gown or apron: Any covering that keeps blood off your clothes and skin. A disposable plastic apron is fine for most household spills.
If the spill involves broken glass or sharp objects, do not pick them up with your hands. Use tongs, a dustpan and brush, or forceps to collect them first.
Choosing the Right Disinfectant
Household bleach (sodium hypochlorite at 5.25% to 6.15% concentration) is the most widely recommended and readily available disinfectant for blood. The CDC recommends two different dilution strengths depending on the size of the spill:
- Small spills (drops of blood): A 1:100 dilution, which is roughly 1 tablespoon of bleach per quart of water.
- Large spills: A 1:10 dilution, which is about half a cup of bleach per quart of water. This stronger solution is also what you should use if there’s any chance of sharp objects hidden in the spill.
If bleach isn’t suitable for the surface you’re cleaning, look for a disinfectant that is EPA-registered and labeled as tuberculocidal. This designation means the product is strong enough to kill the same category of pathogens found in blood. Check the product label for this specific claim. Standard antibacterial sprays and quaternary ammonium wipes used for kitchen counters are not reliable substitutes for blood decontamination unless they carry that tuberculocidal rating.
Mix bleach solutions fresh. Sodium hypochlorite loses potency over time, so a bottle of diluted bleach sitting under the sink for weeks won’t be as effective.
Step-by-Step Cleanup for Hard Surfaces
This process works for tile, laminate, sealed concrete, countertops, and other nonporous materials.
1. Contain the spill. If the blood is still wet, place paper towels or absorbent material around the edges to keep it from spreading. For dried blood, skip ahead to step 2 but avoid scraping or scrubbing aggressively, which creates aerosols.
2. Remove the bulk of the blood. Use disposable paper towels or rags to soak up as much blood as possible. Wipe toward the center of the spill rather than outward. Place all soiled materials directly into a plastic bag.
3. Clean the surface. For large spills, wash the area with soap or detergent and water first. This step removes organic material that can reduce the effectiveness of disinfectant. For small spills (a few drops), you can go straight to disinfection.
4. Apply disinfectant. Flood the area with your bleach solution (1:10 for large spills, 1:100 for small ones) or your EPA-registered tuberculocidal product. The surface needs to stay visibly wet with the disinfectant for at least 10 minutes. Don’t just spray and wipe.
5. Wipe dry. After the contact time, wipe the area with clean paper towels. Dispose of these in the same bag as the other contaminated materials.
Handling Dried Blood Safely
Dried blood is still infectious, but it requires a slightly different approach. The biggest concern is avoiding aerosols. Don’t sweep, vacuum, or vigorously scrub dried blood, as all of these launch tiny particles into the air.
Instead, use granular chlorine products (sold as blood spill kits in many pharmacies and safety supply stores) to cover the dried blood. These granules absorb the material and release a high concentration of chlorine at the same time. After a few minutes, use a scraper and dustpan to collect the absorbed material and dispose of it. Then clean and disinfect the surface underneath using the standard bleach protocol. If you don’t have granular chlorine, carefully dampen the dried blood with your bleach solution to rehydrate it before wiping, which reduces the risk of particles becoming airborne.
Cleaning Blood From Porous Surfaces
Carpet, unfinished wood, upholstery, and drywall present a much harder challenge. Blood soaks into these materials quickly, and surface cleaning alone won’t reach what has been absorbed underneath.
For carpet, blood penetrates into both the fibers and the padding below. You can blot and disinfect the surface, but deep decontamination typically requires professional extraction equipment that pulls contaminated material from within the carpet layers. If the blood soaked through to the pad, replacing both the carpet section and the padding is often the only reliable option.
Wood floors absorb blood into the grain and between boards. If the blood sat for any length of time, surface cleaning may not be enough. The affected wood may need to be sanded down or replaced entirely. Drywall that has absorbed blood almost always needs to be cut out and replaced, since no amount of surface disinfection can reach blood that has soaked into the gypsum core.
For any porous surface with significant blood contamination, professional biohazard cleanup services have specialized equipment and EPA-compliant cleaning agents designed to break down blood in absorbent materials. This is not an area where a DIY approach reliably works for larger spills.
Disposing of Contaminated Materials
Everything that touched the blood, including gloves, paper towels, rags, and any absorbent granules, goes into a heavy-duty plastic bag. Seal that bag, then place it inside a second bag. For household spills involving a small amount of blood, double-bagged waste can generally go in your regular trash.
For larger quantities of blood-contaminated material, or in a workplace setting, regulations vary by state. Medical waste is primarily regulated at the state level, so check with your state environmental or health department for specific disposal requirements. In workplaces covered by OSHA’s bloodborne pathogen standard, contaminated waste must be placed in labeled, closeable, leak-proof containers.
Sharps like broken glass or needles should never go in a regular trash bag. Place them in a rigid, puncture-resistant container (a commercial sharps container or, in a pinch, a thick plastic bottle with a screw lid) before disposal.
Workplace Requirements
If the blood spill happens at work, OSHA’s Bloodborne Pathogens Standard (1910.1030) sets specific legal requirements. Contaminated surfaces must be decontaminated immediately or as soon as feasible after a spill. Only staff who have received proper training and have access to appropriate protective equipment should perform the cleanup. Employers are required to provide all protective gear at no cost to employees.
Employers must also maintain records. Employees who are regularly exposed to blood need hepatitis B vaccination records, and these medical records must be kept for the duration of employment plus 30 years. Training records documenting bloodborne pathogen training must be kept for three years. If your workplace doesn’t have a written exposure control plan, that itself is a violation of the standard.