Yusaku Fujii, Ph.Db

Professor,

Gunma University (Japan)

President,

(NPO) The e-JIKEI Network Promotion Institute (Japan)

PAPR for Everyone: Toward a Wear-Rate Management Network That Unifies Pandemic Control and Privacy Protection -

Why VRAIO-Based Verifiability Is the Essential Infrastructure

As an engineering response to airborne pandemic threats, the presenter has proposed the concept of universal PAPR deployment for the general public [PAPR for Everyone: Foundational Concept and Feasibility]. The central finding is that the effective reproduction number can be controlled through a single variable: the population-level wear rate [PAPR for Everyone: Controlling Rt via Population Wear Rate]. This framework is self-contained and capable of functioning as a population-level infection control measure even in the absence of individual-level wear monitoring.

However, the situation changes qualitatively if the inherent sensor capabilities of PAPR——airflow characterization via differential pressure and PWM signals [PAPR Fluid Model: Airflow via Differential Pressure and PWM], and real-time estimation of respiratory flow and mask leakage [PAPR Fluid Model: Real-Time Respiratory Flow and Leakage Estimation]——can be centrally aggregated via smartphone interfaces. Sensor data generated by citizens at the scale of 100 million in Japan alone would function as an AI-driven big data infrastructure, enabling real-time monitoring, prediction, and intervention in infection dynamics far beyond what conventional contact-tracing applications could achieve. In a sensor-dense society, such AI-driven public safety infrastructure constitutes a new cornerstone of pandemic engineering.

At this point, we must return to a foundational principle of engineering and science: "No measurement, no understanding; no understanding, no control." Insufficient measurement yields only insufficient understanding. Control built upon insufficient understanding is, however carefully designed, inevitably insufficient in turn. In light of this principle, the construction of a system grounded in precise measurement and management of wear rates is an indispensable condition for rendering infection control genuinely worthy of the name [PWS-NET: Wear-Rate Management for Infection Control and Civil Liberties].

Yet this comes with a serious problem. The information collected by PAPR——wear history, behavioral history, and real-time respiratory status——constitutes an aggregation of highly sensitive personal data. When an AI-driven public safety infrastructure operating at the scale of 100 million citizens accumulates biometric and behavioral information, the trustworthiness of that system must be beyond question. Indeed, the fundamental reason why contact-tracing applications around the world failed to collect sufficient measurement data during COVID-19 was not technical limitation, but the social reality that citizens could not trust the systems. Trust in public safety infrastructure is not generated by declarations of good intent; it can only be guaranteed by a verifiable architecture.

The VRAIO (Verifiable Record of AI Output) infrastructure proposed by the presenter is positioned as precisely the answer to this problem [VRAIO: First Proposal, with FMPS as Target]. Through a three-layer architecture comprising tamper-evident output records, spot-check auditing, and asymmetric penalty structures, VRAIO institutionally guarantees accountability and the protection of civil rights in AI-involved systems——giving concrete infrastructural form to the principles of Trustworthy AI, rather than leaving them as mere declarations. The efficiency of infection control and the protection of individual rights are not an unavoidable trade-off. The establishment of a VRAIO-based privacy protection infrastructure is the indispensable condition for elevating PAPR for Everyone into a pandemic engineering framework that is truly ready for societal implementation——and this lecture presents the case for that claim.

 

References

[PAPR for Everyone: Foundational Concept and Feasibility]

Y. Fujii, An Engineering Alternative to Lockdown During COVID-19 and Other Airborne Infectious Disease Pandemics: Feasibility Study, JMIR Biomedical Engineering, Vol.9, e54666, 2024.

https://biomedeng.jmir.org/2024/1/e54666/

 

[PAPR for Everyone: Controlling Rt via Population Wear Rate]

Y. Fujii, Examination of the requirements for powered air-purifying respirator (PAPR) utilization as an alternative to lockdown, Scientific Reports, Vol.15, 1217, 2025. https://www.nature.com/articles/s41598-024-82348-0

 

[PAPR Fluid Model: Airflow via Differential Pressure and PWM]

Y. Fujii, A. Takita, S. Hashimoto and K. Amagai, Estimation of Respiratory States Based on a Measurement Model of Airflow Characteristics in PAPR Using Differential Pressure and PWM Control Signals: In the Development of a Public-Oriented PAPR as an Alternative to Lockdown Measures, Sensors, Vol.25, No.9, 2939, 2025.

https://doi.org/10.3390/s25092939

 

[PAPR Fluid Model: Real-Time Respiratory Flow and Leakage Estimation]

Y. Fujii, The Real-Time Estimation of Respiratory Flow and Mask Leakage in a PAPR Using a Single Differential-Pressure Sensor and Microcontroller-Based Smartphone Interface in the Development of a Public-Oriented Powered Air-Purifying Respirator as an Alternative to Lockdown Measures, Sensors, Vol.25, No.17, 5340, 2025.

https://doi.org/10.3390/s25175340

 

[PWS-NET: Wear-Rate Management for Infection Control and Civil Liberties]

Y.Fujii, Time-managed PAPR use enables a balanced approach to infection control and personal freedom, Scientific Reports, Vol.16, 2878, 2026.

https://doi.org/10.1038/s41598-025-32625-3

 

[VRAIO: First Proposal, with FMPS as Target]

Y. Fujii, Verifiable record of AI output for privacy protection: public space watched by AI-connected cameras as a target exampleAI & Society, Vol.40, pp. 36973706, 2025.

https://doi.org/10.1007/s00146-024-02122-8