The Critical Importance of Measuring Ventilation in Modern Buildings
Simon Jones
Consultancy | Podcast | Speaker | Unlocking better ventilation and air quality. AMIEnvSc, AMIAQM
On World Ventilate Day, we’re reminded of the critical link between ventilation and healthy indoor spaces. As we spend more time indoors, the quality of the air we breathe is increasingly vital—not just for our physical health but also for productivity and cognitive function. Yet, despite our awareness, many indoor environments suffer from poor air quality due to pollutants from household products, cooking, building materials, and insufficient ventilation. With the growing body of evidence linking air quality to health, the challenge lies not only in installing ventilation systems but in ensuring they meet performance standards.
For example, research from Harvard highlights that poor indoor air quality can decrease productivity, reduce cognitive function, and contribute to absenteeism in workplaces and schools. In homes, pollutants like particulate matter and radon can accumulate in poorly ventilated spaces, posing serious health risks over time, from respiratory conditions to cardiovascular issues. These findings stress that merely having a ventilation system in place isn’t enough; we need to accurately measure and validate the performance of these systems to maintain healthy indoor air quality.
Why Accurate Measurement Matters
Proper ventilation can only be assured with precise measurement methods. Standards like the UK's Approved Document F outline various ways to assess airflow, yet research shows a significant gap between regulatory requirements and real-world outcomes. In the UK, up to 38% of residential ventilation systems still fail to meet the required airflow rates, underscoring the need for improved measurement techniques. Meeting these standards is not just a box-ticking exercise; it's essential to creating safe, healthy indoor spaces.
Three primary methods currently guide ventilation measurement: the unconditional method, the conditional method, and the minimum benchmark method, each with its own set of applications and limitations:
These methods have their strengths and limitations. While the unconditional method provides high accuracy, it’s costly and complex. The conditional method is more affordable but demands experienced operators to ensure reliability. The minimum benchmark method, though practical for general checks, sacrifices precision.
Bridging the Gap: A Two-Tier Approach
In light of these challenges, a two-tier approach to ventilation measurement could offer a balanced solution. This model involves certified professionals conducting detailed measurements where high accuracy is needed, while less technical personnel handle basic assessments in routine scenarios.
Implementing a two-tier approach can ensure regulatory compliance and optimise resources. It maximises the impact of trained specialists while empowering a broader group to maintain basic indoor air quality standards. However, for this model to succeed, clear guidelines and checklists must be established to support non-specialists, allowing them to identify and report issues effectively.
Looking Ahead: The Future of Ventilation Measurement
As digital tools and environmental monitoring become more common, we’re approaching a future where ventilation performance will be continuously monitored. Meeting these standards will soon require us to move beyond installation specifications and validate ongoing performance. With regulatory changes like the UK’s potential shift away from the conditional method, there’s a need for significant investment in tools and training to ensure we meet the growing demand for accurate, reliable measurement.
Without proper measurement, ventilation cannot be optimised, and our health may be at risk. Investing in reliable measurement methods today can ensure healthier indoor environments in the future.
For more information, check out https://www.airqualitymatters.net/podcast
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Owner, Abba Energy Ltd. Retrofit Coordination and Sustainable Design Consultancy. Call: 020 820 88333. abbaenergy.com
1 周Yes please, let's hear it loud and proud for Method A. Simple, clear, consistent measurement for lung health. Why risk your next breath with something cheaper?
Improvement Guru. I help organizations become better & make the world better. Lifelong Learner. Always learning about my expertise, my community, my professional partners, & our world. Let’s make our world better.
2 周What does ventilation mean? Does it mean moving air from A to B? Are there quality requirements for sources, like A, or for the breathing area, B? Or for the conditioning? Or the introduction of outside air? And the quality of that air?
Business Manager at BSRIA Compliance
2 周Regrettably, Method C is the most commonly used approach in new builds. Installations are typically “certified” by the installer (often an electrician) who purchases a vane anemometer and hood assembly, chosen as a “cost-effective solution.” However, these systems are rarely calibrated as required, and even if they are, calibration-specific corrections are often ignored. Despite 14 years of mandatory testing in England, ventilation is still undervalued, as evidenced by the fact that failure rates are consistent whether we are conducting initial tests or checking the results of the installers’ tests. Given the significant adverse effects of inadequate ventilation, as highlighted in the article, we should also review the effectiveness of current competency schemes.
Business Manager at BSRIA Compliance
2 周Secondly, I believe that the unconditional methodology (Method A) is the least complex and most straightforward option. These measurement systems come with integral back-pressure compensation, so the reading accurately reflects performance without adjustments. The conditional method (Method B), on the other hand, is more complex. It requires fan performance curves for the installed fans, as well as an understanding of how the chosen measurement device will impact that curve. The minimum benchmark method (Method C) was developed to account for the typical effect of a vane anemometer on fan performance when measurement equipment resistance is present (you can view a demonstration video here). While Method C can provide a rough estimate, it is inherently a rule-of-thumb approach that may fail systems that should pass and vice versa.
Business Manager at BSRIA Compliance
2 周Firstly, while it’s essential to install and commission ventilation systems that deliver effective, real-world performance, we also need to address occupant interaction with these systems. Either we should limit their ability to disable the systems, or we should ensure they have adequate knowledge to actively engage with the solution. Unfortunately, it’s common to find systems switched off at their isolators or background ventilators permanently closed, defeating the purpose of the installation.