Hot tubs are small, warm bodies of water with relatively low water volume, which means contamination can become a serious concern very quickly.
If feces, vomit, blood or another bodily contaminant gets into a hot tub, the safest response is to get everyone out of the water immediately and keep the spa closed until it has been properly cleaned and disinfected.
The exact response depends on what entered the water, but hot tubs require special attention because their warm temperature and small volume can allow germs to spread more easily than many owners realize.
What Should You Do First?
If any significant contamination occurs in a hot tub:
- Get everyone out of the spa.
- Do not allow anyone back in until cleanup is complete.
- Wear disposable gloves when handling contaminated material.
- Remove solid material with a net or bucket when possible.
- Do not handle feces, vomit or blood with bare hands.
- Wash your hands thoroughly with soap and water after cleanup.
The Centers for Disease Control and Prevention identifies feces, vomit and blood among the most common body-fluid contamination concerns in treated recreational water. :contentReference[oaicite:0]{index=0}
What If Someone Has A Fecal Accident In The Hot Tub?
Fecal contamination should always be taken seriously.
Germs that can spread through fecal matter include Cryptosporidium, Giardia, Shigella, norovirus and certain strains of E. coli. Some of these organisms are killed relatively quickly by chlorine, while others can survive much longer. :contentReference[oaicite:1]{index=1}
Cryptosporidium, commonly called Crypto, is especially important because it can survive for days even in properly chlorinated recreational water. :contentReference[oaicite:2]{index=2}
Should You Drain A Hot Tub After Fecal Contamination?
Yes. For a fecal incident in a hot tub, CDC guidance recommends a much more complete response than simply adding extra sanitizer.
The recommended process includes:
- Close the hot tub to bathers.
- Wear disposable gloves.
- Remove the fecal material with a net or bucket.
- Drain the hot tub.
- Drain the plumbing as much as reasonably possible.
- Scrub and clean accessible surfaces that contacted the contaminated water.
- Clean or replace the filter media as appropriate.
- Refill the spa with clean water.
- Re-establish proper sanitizer and pH levels before use.
CDC specifically recommends draining small-volume venues such as hot tubs after fecal contamination rather than attempting to treat the contaminated water in place. :contentReference[oaicite:3]{index=3}
What Sanitizer Levels Should Be Restored After Refilling?
After the hot tub has been drained, cleaned and refilled, CDC guidance for fecal contamination calls for bringing the water to:
- pH between 7.0 and 7.8
- Free chlorine of at least 3 ppm
Those levels should remain in range for at least 30 minutes before the spa is returned to use. :contentReference[oaicite:4]{index=4}
If your spa uses bromine or another sanitation system, follow the spa and sanitizer manufacturer's instructions and verify the water is properly disinfected before anyone gets back in.
What If The Accident Was Diarrhea?
A diarrheal accident is more serious than formed stool because large numbers of disease-causing organisms can be released into the water.
CDC considers diarrheal contamination a high-risk event because it can involve organisms such as Cryptosporidium. :contentReference[oaicite:5]{index=5}
For a residential hot tub, the practical response is straightforward:
Do not try to save the water. Drain the spa, clean and disinfect it thoroughly, address the filter, refill it and restore proper sanitizer levels before use.
What If Someone Vomits In The Hot Tub?
Vomiting can have several causes, and the level of concern depends partly on what was expelled.
CDC notes that if someone vomits primarily swallowed pool water, the likelihood of spreading illness is relatively low. If the vomit contains previously eaten food or other stomach contents, however, germs such as norovirus may be present. :contentReference[oaicite:6]{index=6}
In a hot tub, where the water volume is small, we recommend taking a conservative approach.
If someone vomits into the spa:
- Get everyone out.
- Remove visible material.
- Do not allow anyone back in until cleanup is complete.
- Consider draining and refilling the spa, particularly if the vomit contained food or stomach contents.
- Clean the filter and accessible surfaces.
- Restore proper sanitizer and pH before reopening the spa.
What If There Is Blood In The Hot Tub?
Blood in recreational water understandably causes concern, but the risk is somewhat different from fecal contamination.
CDC states that chlorine kills bloodborne germs such as hepatitis B virus and HIV and that it is not aware of documented cases of someone becoming infected with a bloodborne germ from exposure to blood in a properly maintained swimming pool. :contentReference[oaicite:7]{index=7}
That does not mean blood should simply be ignored.
If there is visible blood in the hot tub:
- Remove bathers.
- Wear disposable gloves.
- Remove any visible blood or contaminated material.
- Confirm that the sanitizer system and filtration are operating properly.
- Clean any contaminated surfaces.
Because hot tubs contain much less water than swimming pools, an owner may still choose to drain and refill the spa if there is a significant amount of blood or if there is any doubt about the condition of the water.
What If Blood Or Vomit Gets On The Deck Or Spa Shell?
Contamination on a hard surface should also be cleaned and disinfected.
CDC recommends:
- Blocking access to the contaminated area.
- Wearing disposable gloves.
- Removing the material with disposable absorbent products.
- Disinfecting the surface with an appropriate disinfecting solution.
- Allowing adequate disinfectant contact time.
- Properly disposing of contaminated cleanup materials.
- Washing hands thoroughly afterward.
CDC provides specific instructions for preparing and using diluted household bleach when an appropriate surface disinfectant is needed. Always follow product labeling and never mix chlorine products with other household or pool chemicals. :contentReference[oaicite:8]{index=8}
What If A Child Has An Accident In The Hot Tub?
Children can have accidents unexpectedly, which is another reason supervision is so important.
If a child has a bowel movement or diarrhea in the spa, treat it as a contamination event regardless of how small it appears.
CDC also advises that people who currently have diarrhea should stay out of pools and hot tubs because even a small amount of contaminated water can expose others to illness-causing organisms. :contentReference[oaicite:9]{index=9}
What If A Pet Gets Into The Hot Tub?
Animals can introduce:
- Fecal bacteria
- Dirt
- Hair
- Skin oils
- Saliva
- Other microorganisms
CDC includes animals among the common sources of recreational-water contamination. :contentReference[oaicite:10]{index=10}
If an animal simply gets into otherwise clean water, the response will depend on the circumstances. At minimum, test the sanitizer and water chemistry, clean the filter if necessary, remove debris and restore proper sanitation.
If the animal urinates, defecates or vomits in the spa, treat the event as a significant contamination incident and drain, clean and refill the hot tub.
What About Urine In A Hot Tub?
Urine is not treated the same way as fecal contamination, but it still adds organic material to the water and increases sanitizer demand.
It can contribute to unpleasant odors, degraded water quality and the formation of irritating disinfection byproducts.
If you suspect substantial contamination:
- Test the sanitizer level.
- Check the pH.
- Allow the filtration system to operate.
- Correct the chemistry as necessary.
- Drain and refill if the water is already old, overloaded or difficult to restore.
Should You Shock The Spa Instead Of Draining It?
For ordinary organic contamination or declining water quality, shocking or oxidizing a spa may be appropriate according to the chemical manufacturer's instructions.
That is different from a fecal accident.
For fecal contamination in a hot tub, CDC recommends draining the water, cleaning accessible surfaces and plumbing, addressing the filter media and refilling the spa. :contentReference[oaicite:11]{index=11}
Simply adding more chlorine is not an equivalent substitute.
Do You Need To Replace The Filter?
The filter should not be forgotten during a contamination cleanup.
Contaminated water has been circulated through it, which means organic material and microorganisms may be trapped in the filter media.
Depending on the filter type, age and contamination event, it may be appropriate to:
- Clean the filter thoroughly.
- Use an appropriate filter-cleaning process.
- Replace the cartridge or filter media if there is doubt about whether it can be adequately cleaned.
CDC specifically recommends cleaning or replacing filter media as appropriate after fecal contamination of a hot tub. :contentReference[oaicite:12]{index=12}
Don't Forget The Plumbing
A hot tub's plumbing system contains water even after the visible spa vessel begins draining.
That matters because contaminated water may have circulated through:
- Jet plumbing
- Suction lines
- Heater assemblies
- Pumps
- Manifolds
- Filter housings
CDC specifically recommends draining hot-tub piping as much as possible after fecal contamination. :contentReference[oaicite:13]{index=13}
Can You Tell Whether Contaminated Water Is Safe Just By Looking At It?
No.
Clear water can still contain microorganisms.
Visual appearance, smell and clarity can provide useful warning signs, but they do not prove that water is microbiologically safe.
CDC recommends maintaining proper sanitizer and pH because disinfectant is the first line of defense against many germs. :contentReference[oaicite:14]{index=14}
A Strong Chemical Smell Does Not Mean The Water Is Extra Clean
A common misconception is that a strong chlorine smell means there is plenty of sanitizer in the water.
CDC notes that a properly chlorinated hot tub should have little odor. A strong chemical smell can actually indicate a water-quality problem. :contentReference[oaicite:15]{index=15}
If a hot tub smells unusually strong, looks cloudy, feels slimy or otherwise appears questionable, do not assume it is safe simply because you can smell chlorine.
When Is It Safe To Use The Hot Tub Again?
Do not reopen the spa until:
- The contamination has been completely removed.
- The spa and affected surfaces have been cleaned.
- The filter has been cleaned or replaced where appropriate.
- The spa has been refilled if required.
- The circulation and filtration systems are operating normally.
- Sanitizer and pH are back within the proper range.
- The water is clear and there are no obvious signs of contamination.
CDC recommends at least 3 ppm free chlorine and a pH of 7.0–7.8 for hot tubs after a fecal-contamination cleanup, maintained for at least 30 minutes before use. :contentReference[oaicite:16]{index=16}
Public, Hotel And Airbnb Hot Tubs Are Different
If a contamination event occurs in a hotel, gym, Airbnb, apartment complex or other public or shared spa, notify the operator or property manager immediately.
Do not attempt to treat or reopen someone else's commercial spa yourself.
Public facilities may be subject to state or local health regulations and should have established contamination-response procedures.
CDC notes that public aquatic facilities should follow applicable state, local, tribal or territorial codes in addition to appropriate public-health guidance. :contentReference[oaicite:17]{index=17}
When Should You Simply Stay Out?
Do not use a hot tub if:
- You know a fecal or vomit contamination event recently occurred and cleanup has not been completed.
- The water is cloudy enough that its condition cannot be evaluated.
- The surfaces feel unusually sticky or slimy.
- The sanitizer level cannot be verified.
- The water has a strong or unusual odor.
- The operator cannot explain whether the spa has been cleaned following a contamination event.
For public hot tubs, CDC specifically recommends checking water clarity, sanitizer, pH, temperature and the condition of surfaces before use. :contentReference[oaicite:18]{index=18}
Preventing Contamination In The First Place
Prevention is much easier than decontaminating a hot tub.
Good habits include:
- Do not use the spa when you have diarrhea.
- Shower before entering the hot tub.
- Do not swallow spa water.
- Supervise children closely.
- Keep pets out of the spa.
- Maintain proper sanitizer and pH.
- Clean filters regularly.
- Drain and refill the spa on an appropriate schedule.
CDC recommends showering before entering, staying out when sick with diarrhea and avoiding swallowing hot-tub water to help reduce the spread of recreational-water illnesses. :contentReference[oaicite:19]{index=19}
The Bottom Line
If feces, vomit or another significant contaminant gets into a hot tub, get everyone out of the water immediately.
Fecal contamination requires the most aggressive response. For hot tubs, CDC recommends draining the spa and plumbing as much as possible, cleaning all accessible contaminated surfaces, cleaning or replacing filter media as appropriate, refilling the spa and restoring proper sanitizer and pH before allowing anyone back in. :contentReference[oaicite:20]{index=20}
Blood presents a different risk profile, but visible contamination should still be removed and the water and surfaces properly managed.
When there is any doubt about whether contaminated hot-tub water is safe, the safer choice is to stay out until the spa has been properly cleaned and the water conditions verified.
For more information about sanitation, unusual water appearance or odor, electrical hazards, children, pets, temperature, drains and other safety topics, visit our Water Safety Knowledge Base.
If you need help replacing a filter, plumbing component, sanitation-system part, pump or another hot-tub component after a contamination cleanup, visit our Find My Part page or contact Bath & Spa Parts Online.