Breathing Blind

People spend approximately 90% of their time indoors, where airborne pathogen concentrations can be 2–5× higher than outdoors. COVID-19 demonstrated that indoor airborne transmission is the dominant route for respiratory pathogens, yet no building in the world can detect the presence of airborne pathogens in real time and automatically adjust ventilation, filtration, or disinfection in response. Current indoor air quality (IAQ) monitoring measures proxies — CO2, particulate matter, temperature, humidity — none of which directly indicate biological threat. Pathogen detection methods that are specific (PCR, sequencing) require hours to days for results, while methods that are fast (particle counters) cannot distinguish pathogens from harmless bioaerosols. This means buildings cannot respond to airborne threats until well after exposure has occurred.

The CDC estimates that building-related illnesses cost $75 billion annually in healthcare costs, lost productivity, and missed work/school days in the U.S. alone. Respiratory infections transmitted indoors (influenza, COVID-19, tuberculosis, RSV) cause millions of hospitalizations and hundreds of thousands of deaths globally each year. The average American office worker occupies shared indoor spaces for 40+ hours per week. Schools, hospitals, nursing homes, and transit systems are particularly high-risk environments where vulnerable populations are concentrated. Despite this, building HVAC systems operate on fixed schedules and temperature setpoints, not on any measure of biological safety.

Environmental monitoring for CO2 (a proxy for ventilation adequacy) is increasingly common but does not detect pathogens. PCR-based air samplers can detect specific pathogens but require sample collection (typically 30–60 minutes of air sampling), laboratory processing, and expert interpretation — making them surveillance tools, not real-time triggers for building response. Continuous bioaerosol monitors (e.g., WIBS, UV-LIF) can count fluorescent biological particles in real time but cannot distinguish pathogenic bacteria from pollen, mold spores, or harmless skin cells — false positive rates exceed 90%. UV-C germicidal irradiation can inactivate pathogens but is applied uniformly regardless of actual threat level, wasting energy and degrading materials. No integrated system exists that combines rapid biological detection, risk assessment, and automated building response.

A three-component integrated system: (1) next-generation indoor air biosensors that can detect and differentiate specific pathogen categories (bacteria, viruses, fungi) in real time or near-real-time (<10 minutes) at low concentrations; (2) respiratory risk assessment software that translates biosensor data plus occupancy, ventilation rates, and vulnerable population presence into actionable risk scores; (3) automated building control integration that triggers ventilation increases, portable HEPA filtration activation, or UV-C deployment in response to elevated risk — creating the first "immune-responsive" building.

A student team could prototype a low-cost continuous air sampling system that feeds into a loop-mediated isothermal amplification (LAMP) assay for a model respiratory pathogen, measuring the minimum detectable airborne concentration and time-to-result. An engineering team could develop a building control algorithm that optimizes the tradeoff between pathogen reduction (increased ventilation/filtration) and energy cost, using CO2 and occupancy data as inputs. Relevant disciplines: environmental engineering, biosensing, HVAC engineering, public health, embedded systems.