IP Library Granted Patent US 12,540,933
Granted Patent B2
US 12,540,933 · App. 18/077,185 · Granted Feb 3, 2026

System and method for characterizing, monitoring, and detecting bioaerosol presence and movement in an indoor environment

Inventors: Sam D. Molyneux (Mountain View, CA); Elizabeth Caley (Mountain View, CA); Daniela Bezdan (Mountain View, CA); Nathan Volman (Mountain View, CA); Laila Ladhani (Mountain View, CA); Kalyan Kottapalli (Mountain View, CA); Konrad Swic (Mountain View, CA); Aaron Botham (Mountain View, CA)
Assignee: Poppy Health, Inc.
G01N33/0075G01N15/06G01N33/0006G01N35/00722A61L2209/111G01N2001/2223
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Quick Facts
Patent No.
US 12,540,933
App. No.
18/077,185
Granted
Feb 3, 2026
Kind
B2
Abstract

One variation of a method includes, during a test period: triggering release of a tracer test load into air in an environment, according to a set of release parameters, by a dispenser arranged within the environment, the first tracer test load comprising a first concentration of tracers of a first type in solution; and triggering an air sampler, located in the environment, to record a timeseries of aerosol data representing amounts of aerosol particles detected at the air sampler during the test period. The method further includes: deriving a tracer signal, representing changes in amounts of tracers in air detected at the air sampler during the test period, based on the timeseries of aerosol data and the set of release parameters; based on characteristics of the tracer signal, characterizing a set of aerosol flow metrics representing behavior of aerosols in the environment during the test period.

Claims (106)

1 . A method comprising:

during a first test period for an aerosol zone:

during a dispense period, triggering release of a first tracer test load into ambient air in the aerosol zone, according to a first set of release parameters, by a dispenser arranged in a first location within the aerosol zone, the first tracer test load comprising a first concentration of aerosolized tracers of a first type; and

recording a first timeseries of aerosol data via a first set of sensors integrated into a first air sampler, in a set of air samplers, arranged in a second location within the aerosol zone, the first timeseries of aerosol data representing amounts of aerosolized particles in ambient air ingested by the first air sampler during the first test period;

deriving a first tracer signal, representing changes in amounts of tracers of the first type in air detected at the first air sampler during the first test period, based on the first timeseries of aerosol data and the first set of release parameters; and

based on characteristics of the first tracer signal and the first concentration, predicting a first air-change rate, in a set of aerosol flow metrics, for aerosolized particles of the first type in the aerosol zone during the first test period.

2 . The method of claim 1 , further comprising:

during a second test period, succeeding the first test period, for the aerosol zone:

during a second dispense period, triggering release of a second tracer test load into ambient air in the aerosol zone, by the dispenser according to the first set of release parameters, the second tracer test load comprising the first concentration of tracers of the first type; and

recording a second timeseries of aerosol data via the first set of sensors integrated into the first air sampler, the second timeseries of aerosol data representing amounts of aerosolized particles in ambient air ingested by the first air sampler during the second test period;

deriving a second tracer signal representing changes in amounts of tracers of the first type in air detected at the first air sampler during the second test period based on the second timeseries of aerosol data and the first set of release parameters;

based on characteristics of the second tracer signal and the first concentration, predicting a second air-change rate for aerosolized particles of the first type in the aerosol zone during the second test period based on characteristics of the second tracer signal and the first concentration;

characterizing a first difference between the first air-change rate and the second air-change rate; and

in response to the first difference exceeding a threshold difference, predicting a first causal pathway for change in air-change rate in the aerosol zone between the first test period and the second test period.

3 . The method of claim 2 :

further comprising:

during the first test period, recording a first timeseries of environmental data via a second set of sensors arranged in the aerosol zone; and

during the second test period, recording a second timeseries of environmental data via the second set of sensors; and

wherein predicting the first causal pathway comprises:

characterizing a second difference between the first timeseries of environmental data and the second timeseries of environmental data; and

predicting the first causal pathway based on the first difference and the second difference.

4 . The method of claim 1 , further comprising, in response to the first air-change rate falling below a threshold rate:

generating a notification indicating the first air-change rate and a prompt to implement a mitigation action, in a set of mitigation actions, configured to increase the first air-change rate in the aerosol zone; and

transmitting the notification to a user affiliated with the aerosol zone.

5 . The method of claim 1 :

further comprising:

during the first test period, recording a second timeseries of aerosol data via a second set of sensors integrated into a second air sampler, in the set of air samplers, arranged in a third location within the aerosol zone, the second timeseries of aerosol data representing amounts of aerosolized particles in ambient air ingested by the second air sampler during the first test period; and

deriving a second tracer signal representing changes in amounts of tracers of the first type in air detected at the second air sampler during the first test period based on the second timeseries of aerosol data and the first set of release parameters; and

wherein predicting the first air-change rate for aerosolized particles of the first type in the aerosol zone during the first test period based on characteristics of the first tracer signal and the first concentration comprises predicting the first air-change rate for aerosolized particles of the first type in the aerosol zone during the first test period based on characteristics of the first tracer signal, characteristics of the second tracer signal, and the first concentration.

6 . The method of claim 1 :

wherein triggering release of the first tracer test load into ambient air in the aerosol zone comprises triggering release of the first tracer test load into ambient air in the aerosol zone, the first tracer test load comprising:

the first concentration of aerosolized tracers of the first type; and

a second concentration of aerosolized tracers of a second type;

wherein recording the first timeseries of aerosol data comprises recording the first timeseries of aerosol data comprising:

a first timeseries of particle amounts representing amounts of aerosols of the first type detected at the air sampler during the first test period; and

a second timeseries of particle amounts representing amounts of aerosols of the second type detected at the air sampler during the first test period;

wherein deriving the first tracer signal based on the first timeseries of aerosol data and the first set of release parameters comprises deriving the first tracer signal based on the first timeseries of particle amounts and the first set of release parameters; and

further comprising:

deriving a second tracer signal representing changes in amounts of tracers of the second type in air detected at the first air sampler during the first test period based on the second timeseries of particle amounts and the first set of release parameters; and

based on characteristics of the second tracer signal and the second concentration, predicting a second air-change rate for aerosolized particles of the second type in the aerosol zone during the first test period based on characteristics of the second tracer signal and the second concentration.

7 . The method of claim 1 , further comprising:

accessing set of zone parameters defined for the aerosol zone;

accessing a risk model linking air-change rates for aerosolized particles of the first type to risk associated with pathogens of the first type in aerosol zones based on zone parameters in the aerosol zone; and

predicting a first risk level for the aerosol zone during the first test period based on the set of zone parameters, the first air-change rate, and the set of zone parameters.

8 . The method of claim 7 , further comprising, in response to the first risk level exceeding a threshold risk:

generating a notification indicating the first risk level for the first pathogen in the aerosol zone; and

transmitting the notification to a user affiliated with the aerosol zone.

9 . The method of claim 1 :

wherein triggering release of the first tracer test load into ambient air in the aerosol zone according to the first set of release parameters comprises triggering release of the first tracer test load into ambient air in the aerosol zone according to the first set of release parameters comprising:

an initial dispense time corresponding to a start of the dispense period;

a duration of the dispense period; and

a dispensation rate representing a rate of release of aerosolized tracers from the dispenser during the first test period; and

wherein deriving the first tracer signal comprises:

calculating a target sampling window based on the first set of release parameters, the target sampling window defining an initial sampling time and a final sampling time;

extracting a second timeseries of aerosol data from the first timeseries of aerosol data, the second timeseries of aerosol data collected during the target sampling window; and

deriving the first tracer signal, representing changes in amounts of tracers of the first type in air detected at the first air sampler during the sampling window between the initial sampling time and the final sampling time, based on the second timeseries of aerosol data.

10 . The method of claim 1 :

wherein deriving the first tracer signal based on the first timeseries of aerosol data and the first set of release parameters comprises:

accessing a signal-processing model configured to intake timeseries of aerosol data and output tracer signals based on release parameters;

based on the signal-processing model, the first timeseries of aerosol data, and the first set of release parameters, identifying a sampling window, within the first test period, predicted to correspond to the first tracer signal;

accessing a second timeseries of aerosol data, in the first timeseries of aerosol data, corresponding to aerosol data recording during the sampling window; and

deriving the first tracer signal based on the second timeseries of aerosol data and the signal-processing model; and

wherein predicting the first air-change rate based on characteristics of the first tracer signal and the first concentration comprises:

extracting a first amount of tracers of the first type detected in air at an initial time within the sampling window;

extracting a second amount of tracers of the first type detected in air at a final time within the sampling window;

predicting a decay rate in amount of tracers of the first type within the sampling window; and

predicting the first air-change rate based on the first concentration, the first amount, the second amount, and the decay rate.

11 . A method comprising:

during a test period:

during a dispense period, triggering release of a first tracer test load into ambient air in an environment, according to a first set of release parameters, by a dispenser arranged within the environment, the first tracer test load comprising a first concentration of tracers of a first type; and

triggering a first air sampler, in a set of air samplers, located in the environment, to record a timeseries of aerosol data via a set of sensors integrated into the air sampler; and

in response to expiration of the test period:

deriving a tracer signal, in a set of tracer signals, representing changes in amounts of tracers in air detected at the air sampler during the test period based on the timeseries of aerosol data recorded at the air sampler and the first set of release parameters;

based on characteristics of the set of tracer signals, characterizing a set of aerosol flow metrics, including air-change rate, representing behavior of aerosols in the environment during the test period;

characterizing infection risk, associated with a set of pathogens, for the environment during the test period based on the set of aerosol flow metrics and a set of zone characteristics defined for the environment; and

in response to infection risk associated with a first pathogen, in the set of pathogens, exceeding a threshold infection risk:

generating a notification indicating risk associated with the first pathogen in the environment; and

transmitting the notification to a user affiliated with the environment.

12 . The method of claim 11 , wherein characterizing infection risk based on the set of aerosol flow metrics and the set of zone characteristics defined for the environment comprises:

accessing the set of zone characteristics defined for the environment;

accessing a risk model linking aerosol flow metrics derived for the environment and infection risk associated with the set of pathogens based on the set of zone characteristics defined for the environment; and

characterizing infection risk in the environment during the test period based on the set of aerosol flow metrics, the set of zone characteristics, and the risk model.

13 . The method of claim 11 , further comprising, during a first time period comprising the test period:

accessing a first set of environmental data recorded during the test period by a second set of sensors arranged in the environment;

during a second test period succeeding the test period:

triggering release of a second tracer test load into ambient air in the environment, according to a second set of release parameters, by the dispenser arranged within the environment, the second tracer test load comprising a second concentration of tracers of the first type; and

triggering the first air sampler to record a second timeseries of aerosol data via the set of sensors;

deriving a second tracer signal, in a second set of tracer signals, representing changes in amounts of tracers in air detected at the first air sampler during the second test period based on the second timeseries of aerosol data and the second set of release parameters;

based on characteristics of the set of tracer signals, characterizing a second set of aerosol flow metrics representing behavior of aerosols in the environment during the second test period;

accessing a second set of environmental data recorded by the second set of sensors during the second test period;

deriving a flow model linking environmental controls to aerosol flow metrics in the environment based on the first set of environmental data, the first set of aerosol flow metrics, the second set of environmental data, and the second set of aerosol flow metrics; and

during a second time period succeeding the first time period:

accessing a third set of environmental data recorded by the second set of sensors at a second time during the live period; and

predicting a second set of aerosol flow metrics for the environment at the second time based on the third set of environmental data and the flow model.

14 . The method of claim 11 , further comprising, during the test period:

triggering a second air sampler, in the set of air samplers, located in the environment, to record a second timeseries of aerosol data via a second set of sensors integrated into the air sampler;

in response to expiration of the test period, deriving a second tracer signal, in the set of tracer signals, representing changes in amounts of tracers in air detected at the second air sampler during the test period based on the second timeseries of aerosol data recorded at the air sampler and the first set of release parameters; and

wherein characterizing the set of aerosol flow metrics comprises characterizing the set of aerosol flow metrics based on the first tracer signal and the second tracer signal, the set of aerosol flow metrics comprising:

a set of flow pathways for aerosol of the first type in the aerosol zone.

15 . The method of claim 11 :

wherein characterizing infection risk associated with the set of pathogens based on the set of aerosol flow metrics comprises characterizing infection risk associated with the set of pathogens based on the air-change rate.

16 . The method of claim 11 :

further comprising:

triggering a second air sampler to record a second timeseries of aerosol data via a second set of sensors integrated into the second air sampler; and

deriving a second tracer signal, in the set of tracer signals, representing changes in amounts of tracers in air detected at the second air sampler during the test period based on the second timeseries of aerosol data and the first set of release parameters; and

wherein characterizing the set of aerosol flow metrics based on characteristics of the set of tracer signals comprises characterizing the set of aerosol flow metrics based on the first tracer signal and the second tracer signal.

Assignments (3)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 14, 2025
From: MOLYNEUX, SAM D.; CALEY, ELIZABETH; BEZDAN, DANIELA; LADHANI, LAILA; KOTTAPALLI, KALYAN; BOTHAM, AARON; SWIC, KONRAD
To: POPPY HEALTH, INC.
Reel/Frame 072019/0667 →
SECURITY INTEREST Recorded Mar 27, 2024
From: POPPY HEALTH, INC.
To: TOP CORNER CAPITAL LP
Reel/Frame 066927/0357 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 21, 2023
From: MOLYNEUX, SAM D.; CALEY, ELIZABETH; BEZDAN, DANIELA; LADHANI, LAILA; KOTTAPALLI, KALYAN; SWIC, KINRAD; BOTHAM, AARON
To: POPPY HEALTH , INC.
Reel/Frame 062750/0596 →
Continuity (7)
Provisional Application 63405340 · Sep 9, 2022
Provisional Application 63355949 · Jun 27, 2022
Provisional Application 63329717 · Apr 11, 2022
Provisional Application 63286821 · Dec 7, 2021
Provisional Application 63286815 · Dec 7, 2021
Provisional Application 63286806 · Dec 7, 2021
Related Publication 20230176024A1 · Jun 8, 2023
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