Spatial and Temporal Variations in Indoor Environmental Conditions, Human Occupancy, and Operational Characteristics in a New Hospital Building

Abstract

The dynamics of indoor environmental conditions, human occupancy, and operational characteristics of buildings influence human comfort and indoor environmental quality, including the survival and progression of microbial communities. A suite of continuous, long-term environmental and operational parameters were measured in ten patient rooms and two nurse stations in a new hospital building in Chicago, IL to characterize the indoor environment in which microbial samples were taken for the Hospital Microbiome Project. Measurements included environmental conditions (indoor dry-bulb temperature, relative humidity, humidity ratio, and illuminance) in the patient rooms and nurse stations; differential pressure between the patient rooms and hallways; surrogate measures for human occupancy and activity in the patient rooms using both indoor air CO2 concentrations and infrared doorway beam-break counters; and outdoor air fractions in the heating, ventilating, and air-conditioning systems serving the sampled spaces. Measurements were made at 5-minute intervals over consecutive days for nearly one year, providing a total of ∼8×106 data points. Indoor temperature, illuminance, and human occupancy/activity were all weakly correlated between rooms, while relative humidity, humidity ratio, and outdoor air fractions showed strong temporal (seasonal) patterns and strong spatial correlations between rooms. Differential pressure measurements confirmed that all patient rooms were operated at neutral pressure. The patient rooms averaged about 100 combined entrances and exits per day, which suggests they were relatively lightly occupied compared to higher traffic environments (e.g., retail buildings) and more similar to lower traffic office environments. There were also clear differences in several environmental parameters before and after the hospital was occupied with patients and staff. Characterizing and understanding factors that influence these building dynamics is vital for hospital environments, where they can impact patient health and the survival and spread of healthcare associated infections.

Pilot study of sources and concentrations of size-resolved airborne particles in a neonatal intensive care unit

“…They further contribute to the observations by Ramos et al [43] on the utility of beam-break counts and "room source CO2" data for inferring occupancy patterns in hospitals.…”

Bacterial colonization and succession in a newly opened hospital

“…One patient room on each level was sampled daily while all other environments where sampled weekly. Environmental conditions, including temperature, humidity, illuminance, CO 2 concentrations and infrared doorway beam breaks were continuously monitored 16–17 .…”

Meat Processing Plant Microbiome and Contamination Patterns of Cold-Tolerant Bacteria Causing Food Safety and Spoilage Risks in the Manufacture of Vacuum-Packaged Cooked Sausages

“…Compared to studies of the microbiota in other man-made environments, such as shopping malls (7), homes (8), and hospitals (9), microbiota associated with food processing facilities have not been analyzed to the same extent using comprehensive microbial ecology approaches. When we were consulted to overcome a processing hygiene problem in a largescale meat processing plant, we decided to approach this challenge by conducting a large-scale 16S rRNA gene amplicon sequencing study.…”