How to Clean and Sanitize an Infrared Sauna Safely

After eight years of recommending infrared saunas to patients, I’ve seen what happens when people don’t clean them properly: bacterial growth, mold in corners, and that musty smell that makes you question whether the health benefits are worth it. The good news is that cleaning an infrared sauna correctly takes less than 10 minutes per session, and you don’t need harsh chemicals that could off-gas when the panels heat up.

Infrared saunas operate at lower temperatures than traditional saunas (120-150°F vs. 170-190°F), which means sweat doesn’t evaporate as quickly and bacteria have more opportunity to colonize wooden surfaces. A 2019 study in Building and Environment found that sauna benches can harbor Staphylococcus aureus for up to 48 hours in humid conditions, which is exactly why I’m particular about cleaning protocols.

Daily Cleaning Protocol (After Every Use)

The most important cleaning happens immediately after each session while the wood is still warm and easier to wipe down. This isn’t negotiable if you want to prevent bacterial buildup.

What You’ll Need

• Microfiber cleaning cloths (at least 3-4 dedicated to sauna use)
• Clean water in a spray bottle
• A second spray bottle with diluted white vinegar solution (1 part vinegar to 3 parts water)
• Natural enzyme cleaner for wood (optional, for stubborn spots)

Step-by-Step Daily Cleaning

1. Wipe down benches and backrests immediately. Use a damp microfiber cloth to remove sweat and body oils while the wood is still warm. Work in the direction of the wood grain to avoid pushing moisture into cracks.

2. Clean the floor. Sweat drips here more than anywhere else. Use a separate cloth dampened with your vinegar solution, then follow with a dry cloth.

3. Wipe down door handles and control panels. These high-touch surfaces need attention with every use. A slightly damp cloth is sufficient—avoid getting water in electronic components.

4. Leave the door open for 15-20 minutes. This allows moisture to evaporate and prevents mold growth in enclosed spaces. I recommend using a small fan for air circulation if your sauna is in a poorly ventilated room.

5. Shake out your towel outside the sauna. Don’t leave damp towels inside between sessions—they’re bacterial breeding grounds.

Weekly Deep Cleaning

Once a week, you need to address areas that daily wiping doesn’t reach: corners, under benches, and the areas around heating panels.

Weekly Cleaning Steps

Vacuum first. Use a brush attachment to remove dust, hair, and debris from corners and under benches. Dust on heating elements reduces efficiency and can create odors when heated.

Clean all wooden surfaces with vinegar solution. Spray lightly—don’t saturate the wood—and wipe immediately with a clean microfiber cloth. Vinegar is mildly acidic (pH 2.5-3.5) and disrupts bacterial cell walls without leaving toxic residues that would off-gas during your next session.

Sanitize floor mats if you use them. Remove and wash according to manufacturer instructions, or replace if they show signs of degradation.

Check drainage (if applicable). Some infrared saunas have small drainage holes in the floor. Make sure these aren’t clogged.

Inspect heating panels. Look for dust accumulation on carbon or ceramic panels. Use a dry microfiber cloth to gently wipe the surface—never use water or cleaning solutions directly on heating elements.

Monthly Maintenance Cleaning

Monthly deep cleaning prevents long-term issues like wood discoloration and persistent odors.

Monthly Tasks

• Sand discolored areas. Sweat and body oils can darken wood over time. Light sanding with 220-grit sandpaper restores the surface. Sand with the grain, then vacuum dust immediately.
• Check for mold in corners. Use a flashlight to inspect corners where walls meet benches. If you see black or green spots, address them immediately (see sanitization section below).
• Clean glass door/windows. Use a natural glass cleaner on the exterior. On the interior, use only water to avoid chemical residue.
• Condition the wood (optional). Some manufacturers recommend food-grade mineral oil or specialized sauna wood conditioner every 3-6 months. Check your warranty first—some void coverage if you use unapproved products.

What to Use (and What to Avoid)

The chemicals you use in an enclosed, heated space matter more than in other areas of your home. When wood reaches 140°F, volatile organic compounds (VOCs) off-gas more readily, and you’re breathing deeply during sauna sessions.

Safe to Use	Why It Works	Avoid	Why It’s Problematic
White vinegar (diluted)	Antibacterial, evaporates cleanly, no toxic residue	Bleach	Releases chlorine gas when heated; damages wood finish
Hydrogen peroxide (3%)	Antifungal, breaks down to water and oxygen	Ammonia-based cleaners	Toxic fumes when heated; irritates respiratory system
Enzyme cleaners (wood-safe)	Breaks down organic matter, gentle on wood	Scented cleaners	Synthetic fragrances contain phthalates; off-gas when heated
Baking soda paste (stubborn spots)	Mild abrasive, deodorizes, no harmful residue	Furniture polish	Creates slippery surface; chemical off-gassing
Plain water	Removes surface contaminants, safest option	Essential oils	Can damage wood finish; many are flammable

How to Sanitize (Not Just Clean)

Cleaning removes visible dirt and sweat; sanitizing reduces microbial load to safe levels. This distinction matters if multiple people use your sauna or if someone has been sick.

Heat Sanitization

The sauna itself provides sanitization when used correctly. Research from Finland’s public health institute shows that temperatures above 140°F maintained for 20+ minutes reduce bacterial counts by 99.9% on wood surfaces. Run an empty cycle at maximum temperature once a week as passive sanitization.

Chemical Sanitization When Needed

If someone with a contagious skin infection has used the sauna, or if you notice mold growth:

For general sanitization: Use 3% hydrogen peroxide in a spray bottle. Apply to surfaces, let sit for 5 minutes, then wipe clean and dry thoroughly. Hydrogen peroxide breaks down to water and oxygen—no toxic residue.

For mold: Mix 1 part hydrogen peroxide with 2 parts water. Spray affected areas, scrub gently with a soft brush, then wipe clean. For persistent mold, you may need to sand the affected wood and treat with a wood mold inhibitor. If mold keeps returning, you have a moisture problem that needs addressing—check for leaks or insufficient ventilation.

For stubborn bacteria (after illness): The CDC recommends quaternary ammonium compounds (quats) for surface sanitization, but these can leave residue. If you use a commercial sauna sanitizer, choose one labeled for food-contact surfaces and ensure it’s completely dry before using the sauna.

Common Cleaning Mistakes That Damage Your Sauna

Over-wetting the wood. Cedar and hemlock are porous. Excessive water causes swelling, warping, and mold growth between boards. Always use damp (not wet) cloths and dry surfaces immediately.

Cleaning while the sauna is hot. Some people think this is more effective, but rapid evaporation leaves cleaning product residue behind. Clean when the sauna is warm but not at operating temperature.

Using abrasive scrubbers. Steel wool or harsh scrub pads damage the wood finish and create tiny scratches where bacteria can hide. Stick to microfiber or soft bristle brushes.

Forgetting the ceiling. Heat rises, which means moisture and dust accumulate on the ceiling. Wipe it down monthly with a microfiber duster on an extension pole.

Neglecting exterior maintenance. If your infrared sauna is in a garage or basement, check the exterior for signs of moisture damage or pest intrusion. Seal any gaps that could compromise the structure.

Special Considerations for Different Sauna Types

Portable vs. Built-In Infrared Saunas

Portable saunas with fabric exteriors need different care. Wipe down the interior wood as described above, but also vacuum or spot-clean the fabric exterior monthly. Check manufacturer guidelines—some fabric exteriors are machine-washable.

Full-Spectrum vs. Far-Infrared

Full-spectrum saunas include near-infrared bulbs that look like red heat lamps. These accumulate dust more visibly. Wipe bulbs gently with a dry cloth when completely cool—fingerprints and dust reduce output efficiency by up to 15%.

If You Have Chromotherapy Lights

LED chromotherapy lights need occasional cleaning. Use a dry microfiber cloth on the lenses. Never spray cleaner directly on light fixtures—moisture in electrical components is a fire hazard.

How to Know If Your Cleaning Protocol Is Working

A properly maintained infrared sauna should smell like wood—cedar, hemlock, or whatever species your sauna uses. If you notice sour, musty, or chemical odors, something’s wrong.

Visual inspection: Wood should maintain its original color. Dark stains, especially in sweat-prone areas like lower backrests, indicate inadequate cleaning.

The white towel test: After cleaning, wipe benches with a white towel. If it picks up yellow or brown residue, you need to deep clean more aggressively.

Post-session comfort: If you’re developing skin irritation or respiratory symptoms during sauna sessions, you may be reacting to either bacterial buildup or cleaning product residue.

Creating a Sustainable Cleaning Routine

The patients who successfully maintain their saunas long-term are the ones who build cleaning into the session routine, not treat it as a separate chore. I keep a small basket in my sauna closet with everything I need: microfiber cloths, spray bottles, and a timer to remind me to open the door after sessions.

If you use your sauna daily, budget 5 minutes for post-session wipedown, 15 minutes for weekly deep cleaning, and 30 minutes monthly for maintenance tasks. That’s about 3 hours per year to protect an investment that typically costs $1,000-5,000.

Frequently Asked Questions

Can I use antibacterial wipes in my infrared sauna?

I don’t recommend it. Most antibacterial wipes contain quaternary ammonium compounds, alcohol, or other chemicals that leave residue and off-gas when heated. They’re also designed for non-porous surfaces like countertops, not wood. Stick to vinegar solution or hydrogen peroxide on a cloth—you get the antibacterial effect without the toxic residue.

How often should I replace the wood in my sauna benches?

With proper maintenance, sauna wood should last 10-15 years. You’ll need replacement sooner if you see deep cracks, persistent mold that returns after treatment, or structural sagging. Surface discoloration isn’t a reason to replace wood—sanding usually restores it. If one section is heavily worn, many manufacturers sell replacement bench boards.

Is it safe to use steam cleaners in an infrared sauna?

No. Steam cleaners introduce excessive moisture that infrared sauna wood isn’t designed to handle—traditional saunas tolerate high humidity because they’re built for it, but infrared saunas operate at lower humidity. Steam can warp boards, loosen joinery, and create perfect conditions for mold growth between layers you can’t see. Stick to damp cloth cleaning.

What should I do if I smell mildew but can’t find visible mold?

Mildew odor without visible growth usually means moisture is trapped somewhere—between wall boards, under the floor, or in the insulation. First, improve ventilation: use the sauna with the door cracked open to reduce humidity, and run a dehumidifier in the room between sessions. If odor persists after two weeks, you may need to disassemble sections to locate and treat hidden mold. This is warranty-claim territory for newer saunas—document everything and contact your manufacturer.

Can I use the same cleaning products I use for my gym equipment?

Most gym equipment cleaners are formulated for vinyl, rubber, and metal—not porous wood in a heated environment. They often contain surfactants, fragrances, and preservatives that aren’t safe for inhalation when volatilized by heat. The cleaning principles are similar (remove sweat and oils, reduce microbial load), but the products need to be heat-safe. Use cleaners specifically labeled as safe for sauna use, or stick to the simple solutions I’ve outlined: vinegar, hydrogen peroxide, and water.