The short answer
How It Works
The unit uses UV light to react with moisture in the air, creating hydroxyl radicals. These radicals oxidize odor molecules, volatile organic compounds, and certain bacteria or mold spores, breaking them down into harmless byproducts like carbon dioxide and water. The process is continuous, so the air is treated as it circulates through the room.
Unlike ozone generators, hydroxyl generators do not produce ozone as a byproduct. This makes them suitable for use while people and pets are present, though you should still follow the manufacturer's instructions. In water damage situations, the pros may place one or more units in affected rooms to combat lingering smells from damp carpets, drywall, or insulation.
Safety Considerations
When used according to the manual, a hydroxyl generator is generally safe for continuous operation in occupied spaces. It does not emit harmful levels of ozone or other irritants. However, you should not place the unit directly next to your face or run it in an enclosed space without adequate air movement, as the UV bulb can be a minor burn hazard if touched.
If you have respiratory conditions like asthma or COPD, talk to your doctor before running any air treatment device. The pros can adjust placement or run times to reduce any irritation. Also, keep the unit away from children and pets to prevent accidental tipping or contact with the hot bulb.
When to Use One
Hydroxyl generators are most useful after water damage, when damp materials create musty odors and encourage microbial growth. They are not a drying tool, so you still need dehumidifiers and air movers to remove moisture. The pros typically run hydroxyl units alongside standard drying equipment, especially in areas with strong smells like crawl spaces or lower levels.
- Reduces musty and smoke odors
- Breaks down VOCs from paints or cleaning products
- Helps control airborne mold spores
- Safe for occupied rooms when used correctly
- Does not produce ozone
- Requires a power source and regular bulb replacement
Limitations to Know
A hydroxyl generator does not kill mold on surfaces or remove water from materials. It only treats the air, so it will not solve the root cause of a smell if wet drywall or carpet remains. You must dry out the space and remove damaged items for the odor to fully disappear.
The effectiveness depends on room size, humidity, and how long the unit runs. Larger areas may need multiple units or longer run times. The pros can assess your situation and decide whether a hydroxyl generator is worth using, or if other methods like thermal fogging are more appropriate.
Renting or Buying One
You can rent a hydroxyl generator from equipment rental shops or buy a consumer-grade model online. Prices vary widely, and the cost depends on the unit's capacity, brand, and whether you rent by the day or buy outright. For a one-time water damage event, renting may be more practical than buying.
Before you spend money, consider the size of the affected area and how long you expect to need the unit. A small room might only require a day or two of operation, while a larger space could take a week. If you are unsure, ask the pros for advice during your water damage inspection.
- Check the unit's coverage area in square feet
- Look for replacement bulbs and filters
- Read the manual for safe placement
- Use a timer to avoid overrunning
- Store the unit away from moisture when not in use
When to Call the Pros
If water damage has soaked carpets, drywall, or insulation, a hydroxyl generator alone will not fix the problem. You need to remove standing water, dry the structure, and often replace porous materials. The pros can handle this with industrial equipment and proper containment.
They can also identify hidden moisture in wall cavities or under flooring that you might miss. Keep your shutoff valve location written down to prevent future leaks. For thorough water damage cleanup, contact a local water damage service to assess the extent and recommend the right approach.
- Standing water deeper than a puddle
- Visible mold growth on surfaces
- Sewage or floodwater contamination
- Persistent musty smell after drying
- Structural damage like warped floors or sagging ceilings
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Call Now (510) 318-3798Frequently asked questions
Can I run a hydroxyl generator while I sleep?
Yes, most models are safe for continuous use in occupied rooms. Keep the unit at least a few feet from your bed and ensure good air circulation. If you feel any irritation, turn it off and consult the manual. For peace of mind, ask the pros for guidance.
Will a hydroxyl generator remove all odors?
It neutralizes many odors, but not all. Strong smells from sewage, smoke damage, or mold may require additional cleaning and removal of contaminated materials. The unit works well on mild to moderate odors in a dry, ventilated space.
How long should I run it after water damage?
Run it continuously until the area is fully dry and the smell is gone, which often takes 2 to 5 days. The exact time depends on humidity, room size, and the extent of the damage. The pros can offer guidance based on your specific situation. Policies vary, and your insurer decides what is covered.