
Many companies loudly claim that “disinfecting” ventilation ducts is a necessary procedure for improving indoor air quality and preventing health risks. However, the honest truth is that this is largely a marketing ploy. I’ve been in this industry for a long time, and IVAeris Oy has lost out on several contracts simply because we refuse to provide this sort of “chemical spraying.” We won’t offer duct disinfection in the future either, because we don’t believe in scams.
I wanted to confirm my position directly with the authorities, so I contacted the Finnish Safety and Chemicals Agency (TUKES) and spoke with Senior Officer Hannu Mattila, who specializes in biocides. The response was clear:
TUKES does not recommend any chemicals for disinfecting ventilation ducts.
The European Chemicals Agency (ECHA) has not granted approvals for duct use to chemicals that would be both safe and completely VOC-free.
What does this mean in practice? It means there is no official basis for disinfection, nor is there any evidence that it improves indoor air quality or reduces health issues. Most companies justify chemical treatments by claiming they “improve indoor air,” but if neither TUKES nor ECHA can find a foundation for this, it’s quite obvious what’s going on.
In short, disinfecting ventilation ducts is a marketing-driven service with no official support. At IVAeris Oy, we refuse to perform pointless chemical spraying, even if it costs us certain contracts. Professional pride and a fact-based approach take precedence over quick profits—both now and in the future.
Why is duct disinfection just unnecessary hype?
Many companies claim that chemically disinfecting ventilation ducts is essential to solving indoor air problems. In reality, there is no credible scientific basis for this. Most of the arguments stem from marketing, scare tactics, or vague “just in case” rationales, none of which are supported by official statements or independent studies.
No scientific evidence of health benefits
So far, no one has conclusively proven that disinfecting ventilation ducts prevents illnesses or health problems.
Dust in the ducts typically sticks to the duct surfaces and does not circulate significantly into indoor air.
If the goal of cleaning is to reduce allergens or other health hazards, standard mechanical cleaning is sufficient—and even that is only necessary if there is a clear need, not “just in case” on a regular schedule.
TUKES’ stance:
The Finnish Safety and Chemicals Agency (TUKES) does not provide guidance on the necessity or frequency of “disinfection,” because there is no basis for such recommendations.
All substances used for disinfection fall under the EU Biocidal Products Regulation. If a product is not officially approved for duct use, it is essentially sold at the company’s own risk. There is no official support for “duct disinfection,” and the European Chemicals Agency (ECHA) has not issued any license for these substances to be used in ventilation ducts.
VOCs and chemical residues:
Spraying disinfectants into ducts always carries the risk of leaving residues that can evaporate into the indoor air and remain in circulation for a long time.
For example, hydrogen peroxide (an oxidizing agent) can damage metals, isopropanol can release VOC emissions, and quaternary ammonium compounds (QAC) can be irritating or even corrosive.
These substances were never originally intended for residential ventilation duct interiors, and the risks or residue formation involved have not been comprehensively studied.
Examples of chemicals in use
In the ventilation industry, several disinfecting products are marketed, such as:
Novitrol 483 disinfectant solution (quaternary ammonium compounds: benzyl-C12-16-alkyldimethyl chloride)
FUNGAL & BACTERIAL DISINFECTION® (DuoQuat®) (quaternary ammonium compounds)
PENETROX® (hydrogen peroxide, DDAC)
ODOX® DF (hydrogen peroxide, DDAC, alcohol as carrier)
MAXOX® DF (hydrogen peroxide, DDAC, alcohol as carrier)
ODOX® (balanced hydrogen peroxide, DDAC-quat)
The active ingredients in these products can be corrosive, irritating, or harmful, and the intended use of each product must always be checked according to the manufacturer’s instructions and current legislation. All these products come with Safety Data Sheets (SDS), which should be carefully reviewed.

Hazards and risks
Skin irritation or corrosion: Quaternary ammonium compounds can damage skin or the respiratory tract if exposure is significant.
Metal corrosion: Hydrogen peroxide is a strong oxidizer that can corrode certain duct materials.
VOC emissions: Alcohol or other organic compounds can evaporate into the indoor air and cause issues, especially for more sensitive individuals.
Residue buildup: When such substances are sprayed into ducts, some may remain on surfaces and be released into the indoor air over time.
What is the best approach?
Use common sense: If your ducts do not have microbial growth, mold, or other unusual issues, chemicals are unlikely to solve any “air quality problems.”
Ask the manufacturer or seller: Does the product in question have official approval for this use? Typically, the answer will be vague or negative.
Clean mechanically—if necessary: Replacing filters and brushing the ducts is usually enough.
Always consider the risk-benefit ratio: Few people want unnecessary chemicals in their indoor air, so disinfection should always be justified with strong evidence if it’s ever carried out.
Ventilation duct “disinfection” might sound appealing as a quick fix for better indoor air, but it’s wise to be skeptical. Studies do not demonstrate health benefits, there are no official guidelines, and many of the chemicals used can be hazardous or questionable when introduced into the ventilation airflow. If you want a healthy and energy-efficient home, focus on the basics: regular filter changes, adequate ventilation, and mechanical cleaning when needed. Costly “disinfectants” have not been proven necessary unless a specific situation calls for them—and even then, consult an expert who understands the risks and chemical safety regulations.

What about cleaning then?
If you do choose to clean your ventilation ducts, that’s a different matter from disinfection. Nor is cleaning automatically “required every year” or even every five years – the old regulations (802/2001) ceased to be valid as of 1 January 2007. According to the current Rescue Act (379/2011):
Cleaning must be performed if the ducts are clearly dirty or if they present a fire safety risk.
Restaurant and commercial kitchen grease ducts are a special case: they must be cleaned regularly (at least once a year) due to the real risk of fire load.
Routine cleaning is not a health guarantee
It’s not scientifically proven that cleaning ducts alone will protect you from allergies or other health issues.
If there is visible dirt or mold in the ducts, then cleaning is obviously a good idea—but that’s different from “disinfection just in case.”
The main benefits of cleaning are controlling energy consumption and extending the system’s service life. Clogged ducts strain the fans, leading to higher electricity bills and faster wear.
Why is disinfection so popular?
Marketing: Someone comes up with a new “service” and sells it as a solution for all indoor air worries. In reality, an air quality problem may be due to moisture, structural damage, or dirty filters—not necessarily “microbes” on duct surfaces.
Fear tactics: Customers may be told “microbes are breeding in your ducts” and causing illnesses, even if there’s no objective evidence for this.
What should you do?
Ask for proof: If someone recommends disinfecting your ducts, request concrete research findings or official approvals. They don’t exist, because no real evidence supports the necessity or benefits of such disinfection.
Trust mechanical cleaning—if needed: Check duct conditions regularly, and clean only if you see or detect dirt, clogs, or other obvious issues. There’s no need for expensive chemical treatments alongside standard cleaning.
Don’t fall for extra chemicals: Disinfection is marketed as a solution to indoor air problems, but TUKES has not given the “green light” for use in ventilation ducts. Extra biocides may release harmful VOC emissions and residues into the indoor air.
Competence in the game: Make sure the technician has sufficient expertise and up-to-date knowledge of the legislation—not outdated regulations.
The Finnish HVAC Association (Suomen LVI-liitto) grants personal competence certificates. Obtaining them requires formal training, an exam, and at least two years of work experience in the field.
Ventilation measurement certification is valid for five years, so ensure the professional’s skills are up to date.
SuLVI maintains a registry of qualified personnel. Ask for a qualification certificate to confirm the service provider holds valid duct-cleaning credentials.
Disinfecting ventilation ducts is a scam with no official support, no legitimate permits, and no scientific basis. It’s primarily a marketing-driven money-making scheme that can, at worst, worsen indoor air through unnecessary chemical residues. Keep your system in good condition and clean the ducts only when there’s an actual need—don’t pay for any “disinfection show.” It won’t protect you from allergies, won’t significantly reduce dust, and isn’t legally required. If you truly want to improve your indoor air quality, focus on the fundamentals: adequate ventilation, clean filters, and high-quality mechanical cleaning when necessary.
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IVAeris Ltd.
010 206 3000