Pure Maintenance Austin TeamQuick answer: Ozone and hydroxyl generators react with odors in the air, UV lights work only on what they shine on, and thermal fogging is a smoke restoration tool. Dry fog reaches every room and the ductwork without wetting things. Ozone belongs only in an empty home, run by trained pros.
How do these five tools compare?
They work in completely different ways, and each has real limits. The names get lumped together, especially if you've dealt with a restoration company, so here they are one at a time.
We're a dry fog company that also uses ozone for persistent odors, so we'll say that upfront and tell you where each tool makes sense.
What does an ozone generator do?
How they work
An ozone generator makes ozone and blows it into a room, where it breaks down many odor-causing compounds. Ozone is a gas made of three oxygen atoms (O3); the oxygen we breathe has two. The machine uses electricity to split oxygen, and the ozone it forms is very reactive. That's why these machines are popular for smoke smells, car interiors and fire and flood cleanup work.
The limits
- Ozone is a lung irritant. The U.S. Environmental Protection Agency (EPA) has published guidance on ozone generators sold as air cleaners. It explains that ozone can irritate the lungs, and that at levels that don't harm people, ozone is not an effective way to clean indoor air. The EPA's advice is to use proven methods instead: control the source, ventilate, and use good filtration.
- People, pets and plants have to leave. Rooms treated at high ozone levels must be empty, and they need time to air out before anyone comes back.
- It can wear on materials. Ozone reacts with rubber, some plastics, fabrics and artwork, and high levels over time can age them faster.
- It can create new byproducts. When ozone reacts with chemicals from cleaners, air fresheners and furniture, it can form other compounds in the air.
- It works on odors, not buildup. Ozone doesn't lift dust, dander or residue off surfaces.
When it makes sense
Ozone is a strong odor tool, but it belongs only in an unoccupied home, run by trained professionals with strict precautions. That's how we use it: our Odor Treatment follows the dry fog with an ozone shock treatment for persistent odors. The ozone runs for up to 48 hours with nobody inside, and the home is aired out before anyone returns.
What the EPA warns against is different: plug-in consumer ozone generators running in rooms where people live day to day. We don't recommend those.
What do UV lights do?
How they work
UV lights shine ultraviolet light, specifically UV-C, which affects many microbes it hits directly. In homes, they're most often installed inside the HVAC system, aimed at the indoor coil or placed in the ductwork. Some portable air filters also include a small UV lamp.
The limits
- UV only reaches what it shines on. Anything in a shadow, behind a fold, under dust or around a corner doesn't get the light. A lamp aimed at the coil doesn't do anything for your couch, closets or ceilings.
- Airborne time is short. In moving air, particles pass by a UV lamp in a fraction of a second, which limits what the light can do to them.
- Bulbs fade. UV bulbs lose strength over time, even when they still glow. Most need replacing about once a year.
- Eyes and skin. UV-C light can harm eyes and skin, so it should only be used inside closed equipment. Some lamps also give off ozone, so look for ones labeled ozone-free.
When it makes sense
A UV light at the indoor coil is a reasonable add-on for many HVAC systems. The coil stays wet while your AC runs, and a steady light can help keep that surface cleaner between maintenance visits. If you're curious whether it fits your system, our sister company Gold Eagle Services installs and services HVAC air quality equipment.
What does a hydroxyl generator do?
How they work
A hydroxyl generator uses UV lamps to turn water vapor and oxygen in the air into hydroxyl radicals, very short-lived molecules that react with many odor-causing compounds in the air. Water and fire restoration companies often use them after smoke or water jobs. Some are made to run in the background in homes and businesses.
The limits
- They work slowly. Hydroxyl radicals last only a moment and are made in small amounts, so jobs are usually measured in days, not hours.
- They mostly work on what's in the air. They don't lift residue off ceilings, cabinets, carpet or the inside of ducts, which is where a lot of odor lives.
- Results depend on the machine and the room. Output, room size, run time and humidity all make a difference, and the equipment is costly to own.
- They can create byproducts. Like ozone, the reactions can form other compounds, and some units give off a little ozone too, so read the manufacturer's guidance on occupied rooms.
When it makes sense
Hydroxyl generators are a slower, gentler odor tool that a restoration company may run for several days after a smoke or water job. They're something to ask your restoration contractor about, not usually a do-it-yourself fix. We don't use them in our treatments.
What is thermal fogging?
How it works
Thermal fogging heats a deodorizing solution, often oil- or solvent-based, until it comes out as a thick, smoke-like fog. The heated fog is meant to follow the same paths smoke did, into gaps and porous materials, and meet the odor where it settled. Fire restoration companies use it for smoke odor.
The limits
- The home has to be empty, and the fog can set off smoke alarms, so trained operators handle it with care.
- Heat and flammable solutions need caution. Pilot lights and ignition sources are turned off, and it isn't a job for rented equipment.
- It can leave a film or a fragrance. Oil-based products can leave residue on surfaces, and some mostly add a strong scent that fades over time.
- It's mainly a smoke odor tool. It isn't built for everyday freshening of a lived-in home.
When it makes sense
Thermal fogging belongs to fire and smoke restoration work, usually after the soot cleanup and alongside insurance claims. It's different from a dry fog: our VaPURE system doesn't heat anything. It breaks a water-based solution into droplets small enough to float and reach every room without getting things wet, and the solution breaks down into water, oxygen and vinegar.
What is dry fog?
How it works
Dry fog is a liquid broken into extremely small droplets, smaller than about 10 microns. They're light enough to float through the air and bounce off surfaces instead of soaking in, so things don't get wet.
Our team uses the patented Pure Maintenance VaPURE dry fog system, in two steps:
- A fine dry fog of a hydrogen peroxide and peracetic acid solution. It breaks down into water, oxygen and vinegar.
- A surface protectant, to help surfaces stay cleaner going forward.
Air compressors create gentle positive pressure, which helps drive the fog into every room, closet, crack and crevice, and through the HVAC ductwork. On treated hard, non-porous surfaces it helps neutralize odors.
The limits
- It's a treatment, not a fix for the cause. A leak, high humidity or a failing AC will keep raising the bio-load (the buildup of particles and microbes in a home) until it's repaired.
- The home needs to be empty during treatment. People and pets step out while the team works. The dry fog treatment is done in one day.
- It doesn't replace everyday cleaning. Wiping, vacuuming and filter changes still matter.
When it makes sense
Dry fog is a good fit when you want every room, closet, ceiling and the ductwork reached at once without soaking your belongings. Families often schedule it after a move, a renovation or a new pet. If that sounds like your home, our whole-home dry fog treatment is the work we do every day, and a short phone call will tell you whether it fits.
How do they compare side by side?
- Ozone: a strong odor tool and a lung irritant; for trained pros in empty homes only, never plug-in units in occupied rooms.
- UV lights: light that works only on what it shines on; a good coil add-on inside the HVAC; needs yearly bulb changes.
- Hydroxyl generators: a slow odor tool that works mostly on the air, run for days by restoration companies; doesn't lift residue from surfaces.
- Thermal fogging: a heated, smoke-like fog for fire and smoke restoration; empty home, trained operators, and it can leave a film or scent.
- Dry fog: very small droplets that travel through the whole home and HVAC without wetting things; done in a day; works best alongside humidity control and good habits.
What should you fix first?
Fix the basics before any machine: keep indoor humidity at 50% or below, change your HVAC filter on schedule, run bath and kitchen fans, and keep your AC coil and drain line clean.
We don't measure or analyze indoor air. If you want to know what's in your air, or you've had a leak or visible growth, start with an independent state-licensed professional.
Get a free phone consultation
Pure Maintenance Austin, brought to you by Gold Eagle Services, serves all of Central Texas, out to College Station (about 2.5 hours), including Round Rock, Georgetown, San Marcos, Bastrop and Marble Falls. Book a free phone consultation: a Comfort Advisor calls you, learns what's going on in your home and sends a written quote based on square footage. Call 512-904-4646 or email IAQ@goldeagleservices.com.