Table 1.

Study design and intervention conditions

Condition	Pre-intervention (Dec. 1–5, 2014)	Intervention (Dec. 6, 2014 – Jan. 13, 2015)	Post-intervention (Jan. 14–31, 2015)
Duration	5 days	39 days	18 days
Biomarker sampling visits	Visit 1 (Dec. 2–5, 2014)	Visit 2 (Dec. 23–26 & 30, 2014) & Visit 3 (Jan. 6–8 & 13, 2015)	Visit 4 (Jan. 27–30, 2015)
Group A
Filtration	F8 + ESP + HEPA	F8	F8 + ESP + HEPA
Office Location	Office A	Office A	Office A
Living Quarters	Dorm Buildings 1–6	Intervention A Dorm	Intervention A Dorm
Group B
Filtration	F8 + ESP + HEPA	F8 + HEPA	F8 + ESP + HEPA
Office Location	Office B	Office B	Office B
Living Quarters	Dorm Buildings 1–6	Dorm Buildings 1–6	Dorm Buildings 1–6