International Indoor Air Quality Institute

Healthy Indoor Air Quality Certificate For Residential Properties

Promoting Healthier Living Environments Worldwide


We understand the importance of breathing clean air, especially within the sanctuary of a home. But did you know that the air you breathe indoors can significantly impact your health and well-being? Poor IAQ can lead to a range of health problems, from respiratory issues, like asthma to lung irritation, to headaches and fatigue.

We believe that everyone deserves to breathe clean, healthy air in their homes so we created our Healthy IAQ Certificates for residential properties to provide independent verification that your living spaces meet our rigorous air quality standards, enhancing the well-being of homeowners and occupants.


Benefits For Homes and Residential Properties

  • Create a Healthier Home for Your Family or Your Tenants or Buyers: Protect them from the risks associated with poor indoor air quality, such as respiratory problems, allergies, and other health issues.
  • Improve Sleep Quality and Overall Well-being: Clean air contributes to better sleep, increased energy levels, and improved overall well-being for everyone in your household.
  • Increase Property Value and Marketability: A Healthy IAQ Certificate may add value to properties and makes it more attractive to potential buyers or renters.
  • Peace of Mind: Enjoy the peace of mind knowing that your house or apartment meets the highest standards for indoor air quality.

Who Should Get Certified

Our Healthy IAQ Certificates are available for a wide range of residential properties, ensuring that regardless of the type of building or home, we can provide a certification for your indoor air.


  • New Houses and Apartments
  • Energy Retrofitted Homes
  • Renovated Homes
  • Rental properties
  • Real estate Investments  (Built To Rent, Student Accommodation)
  • Social Housing

Why Choose Our Certification Program

  1. Scientifically Grounded
    • Our certification program is firmly grounded in the latest scientific research. We draw insights from reputable sources such as the World Health Organization (WHO) and leading universities.
    • By staying abreast of advancements in indoor air quality, we ensure that our guidance is accurate, evidence-based, and relevant.
  2. Industry Standards
    • At our core, we adhere to industry best practices and recognized standards, including the new BS 40102 .
    • This commitment ensures that our program maintains credibility, reliability, and alignment with established guidelines.
  3. Most Comprehensive Indoor Air Quality Certification In The World
    • 11 Indoor air quality parameters measure: Temperature, Humidity, CO2, CO, VOCs, Formaldehyde, O3, NO2, PM 2.5, PM 10, Radon
    • No other certification program covers such a comprehensive range of pollutants.

Certification Process

Step 1

Application and Payment Submission

  • Submit an application for the Healthy Indoor Air Quality Certificate.
  • The application includes relevant details about the property, such as its type, location, and contact information.
  • Payment of the registration fee is processed at this stage.
Step 2

Engagement with an IIAQI Assessor Accredited Professional


  • Once the application is received, it is essential to appoint an IIAQI Accredited Professional.
    • If you have yet to select an Accredited Professional, our directory is available to assist you in finding a qualified individual.
  • They will assess your indoor air quality and provide a report and will also act as the primary point of contact throughout the certification process.


Please be aware that the fees for the services of an IIAQI Assessor Accredited Professional, which include the Healthy IAQ Certificate assessment and any consulting work, are separate from our registration and data review fees.

Step 3

On-Site Assessment by the IIAQI Assessor

The IIAQI Assessor visits your premises to conduct the assessment.

Key activities during the on-site visit include:

  • Layout Inspection: The Assessor examines the property/space layout, including room configurations, ventilation entry and exit points, and ventilation systems available.
  • Occupancy Analysis: The Assessor records the number of people in each room or area.
  • IAQ Monitors Placement: IAQ monitors will be strategically placed in compliance with our standards. The Assessor will also capture photographic evidence to verify correct monitor installation.
Step 4

Data Collection and Review


  • The IAQ monitors collect data over 9 days.
  • Our Data system receives the data from the monitors and compiles the data.
  • We review the data for compliance with our published standards.
Step 5

Certificate Issuance

  • If the data demonstrates compliance, the Healthy Indoor Air Quality Certificate is issued.
  • The certificate includes the respective grade based on the overall IAQ performance.
  • The certificate is issued, which can be displayed prominently and proudly

Certification Grades

This is the basic level of certification. It signifies that the residential space indoor air quality meets the minimum requirements for acceptability in relation to IIAQI Healthy IAQ Certificate Standards.

The parameters measured include temperature, humidity, particulate matter (PM2.5 and PM10), carbon dioxide (CO2), volatile organic compounds (VOCs), formaldehyde, ozone (O3), nitrogen dioxide (NO2), carbon monoxide (CO), and radon. The readings for these parameters must be within the acceptable range defined by IIAQI Healthy IAQ Certificate Standards. 

The next level beyond Rate C certification, grade B indicates a higher standard of IAQ.

At this level, the indoor air quality parameters are measured to ensure that they show “low” measurements in relation to IIAQI Healthy IAQ Certificate Standards, including Temperature, Humidity, PM2.5, PM10, CO2, VOCs, Formaldehyde, O3, NO2, CO, and Radon.


Residential properties that attain this certification surpass the stringent performance metrics 

This level of certification is achieved when the IAQ readings show “very low” readings for all indoor air quality parameters measured, including Temperature, Humidity, PM2.5, PM10, CO2, VOCs, Formaldehyde, O3, NO2, CO, and Radon, in relation to IIAQI Healthy IAQ Certificate Standards.

The Healthy IAQ Grade A+ is the highest level of certification, and it requires that the residential property demonstrates “very low” readings for all indoor air quality parameters and outdoor air quality parameters measured against IIAQI Healthy IAQ Certificate Standards. This includes measurements of Temperature, Humidity, PM2.5, PM10, CO2, VOCs, Formaldehyde, O3, NO2, CO, and Radon.

Healthy Indoor Air Quality Certificate Pricing For Residential Properties

The cost of certification varies depending on the level of certification and the size of your building. Please contact us for a quote tailored to your specific needs. Payment is due upon submission of your application.

Case Studies

Coming Soon

Frequently Asked Questions (FAQs)

What is an IIAQI Assessor Accredited Professional

An IIAQI Assessor Accredited Professional is a qualified and experienced professional who has been accredited by the IIAQI to assess indoor air quality.

How long does the certification process take?

The certification process typically takes about 4-6 weeks, but this can vary depending on the complexity of the assessment and the time it takes to address any issues that have been identified.

Can I appeal a certification decision?

Yes, if you are not satisfied with a certification decision, you can appeal the decision.