As human beings, maintenance of our physical bodies unequivocally requires a few core ingredients from our environment. To survive, we must eat food to get glucose for cellular functioning, drink water to stay hydrated and maintain osmotic pressure, and breathe to acquire oxygen and discharge waste gases. Given this dependence on food, water, and air, we should be on the lookout for unintentional exposures through ingestion and respiration that could support or harm our health.
In the industrialized world, finding information on the ingredients of food is fairly easy and sometimes impossible to ignore, as in the case of the calorie count of a chocolate chip cookie from Starbucks. The compounds in water are also easily discovered by reading the fine print on a bottle label or testing your potable water.
Unfortunately, visibility into unintentional exposures from the air we breathe is often lacking. Data says the average person inhales approximately 11,000 liters of air per day of which 85%, or roughly 9,350 liters, are from the indoor environment. We usually have little idea if we are drawing healthy or unhealthy air into the depths of our vulnerable lungs. Relying on our five senses to detect microscopic particles or non-aromatic gases and chemicals is unrealistic, or, more accurately, impossible. We can only hope that HVAC professionals have reliable medical data to inform their decisions.
Indoor air standards do exist; however, their correlation with occupant health is tangential at best. These standards, or “best practices,” vary by country, season, building type, and a myriad of economic drivers. A quick look into the history of ventilation reveals that recommendations have fluctuated broadly, while human lungs and respiratory requirements have remained unchanged. This fact alone highlights a worrisome disconnect between the regulation of indoor exposures and occupant health.
We can now bridge this chiasm. Integrating knowledge from medicine, microbiology, physics, and material science can create visibility into the key indoor air components that impact health. This integrated approach goes beyond reporting IAQ as simply the sum of single-dose measurements held up to building benchmarks. To truly determine the health impact of multiple indoor air factors that can combine during their interactions, the measured data must be aggregated, analyzed, and processed from the perspective of human physiology and anatomy.
Our ability to intelligently manage multifaceted indoor ecosystems is not a far-fetched dream. In fact, a sophisticated system with multiple inputs, centralized data integration and analysis, and effective output signals has protected living organisms for millions of years. This system is the neuron.
Back to the Future
For many centuries, indoor air management was considered essential to preventing widespread illness, especially infectious diseases. When affordable air conditioners were introduced in the early 1900s, the goal of HVAC systems shifted to maintaining thermal comfort in all seasons. The oil crisis in the 1970s pushed occupant comfort aside to prioritize standards that promoted energy conservation. The COVID-19 pandemic has conclusively reminded us that indoor air management is key in protecting us from infectious diseases. Combining this lesson with integrated knowledge and technology, we can take a huge leap forward in creating indoor environments that truly support human health, boost productivity, decrease job and school absenteeism, and alleviate the economic burden of many diseases.