An interventional study of Filtration Fan and Safe-home pamphlet in Covid19, sponsored by Stanford University. Completed at 2 sites in United States. Per ClinicalTrials.gov, last updated 2026-02-19.
Sponsored by Stanford University · Not applicable, Interventional, and Prevention
Investigators are evaluating whether an intervention consisting of box-fans with MERV 16 filters ("filtration fans") and recommendations for improving ventilation in the home can reduce secondary spread of Covid19 from an index case to susceptible contacts within the home.
7,640 studies on the registry are indexed under COVID-19; 488 are open to participants now.
This study's enrollment of 214 is above the median of 100 across 4,099 interventional studies indexed under COVID-19.
Browse COVID-19 studies →Stanford University is the lead sponsor of 2,117 studies on the registry; 425 are open to participants now.
Of its 259 completed or terminated interventional studies of FDA-regulated products, 197 (76%) have results posted.
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Exclusion Criteria:
No intervention will be administered in this arm. Investigators will give families a CO2 monitor to measure average CO2 levels in the home. Investigators will provide a link to the basic CDC isolation guidelines which would be part of standard of care. Investigators will test family members at day 0-1 for baseline testing; and again on day 7 for assessing secondary transmission among susceptible contacts.
Families are provided with one filtration fan unit per room in their home (and one for the index case; if the family lives in a studio, they would receive 2 units). Investigators will advise families on ventilation improvements in their home. Investigators will provide an instructional pamphlet that describes how the fans work and the importance of ventilation. Investigators will follow-up on day 3-4 to check in and run through a checklist to ensure the fans are working and ventilation improvements are being attempted. Investigators will give families a CO2 monitor to measure average CO2 levels in the home. Investigators will test family members at day 0-1 for baseline testing; and again on day 7 for assessing secondary transmission among susceptible contacts.
Device: Filtration Fan · Behavioral: Safe-home pamphlet · Behavioral: Mid-week phone call
Investigators are using box fans with attached MERV16 filters, a design that has been tested and published in the scientific literature.
The pamphlet has information on how the filtration fans work through visual images; and images of ventilation improvements in the home through opening windows.
On day 3-4 of the study, the study coordinator assigned to the house will call and check in regarding the filtration fan usage and remind families about the importance of filtration and ventilation.
Incidence of Covid19
Investigators will measure the incidence of Covid19 in susceptible contacts on day 7.
Time frame: 7th day since enrollment in the trial
Incidence of new upper respiratory symptoms
Investigators will measure reported new upper respiratory symptoms in susceptible contacts.
Time frame: 7th day since enrollment in the trial
Average CO2 levels
Investigators will measure 7 day average CO2 levels in the home (measured in parts per million)
Time frame: 7 days
Plan to share: No
No publications or documents are linked to this record.
This study is completed, as verified in Feb 2026. You cannot join it, but the record below documents what was studied.
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