Worker productivity and ventilation rate in a call center: Analyses of time-series data for a group of registered nurses

We investigated the relationship of ventilation rates with the performance of advice nurses working in a call center. Ventilation rates were manipulated; temperatures, humidities, and CO₂ concentrations were monitored; and worker performance data, with 30-minute resolution, were collected. Multivariate linear regression was used to investigate the association of worker performance with indoor minus outdoor CO₂ concentration (which increases with decreasing ventilation rate per worker) and with building ventilation rate. Results suggest that the effect of ventilation rate on worker performance in this call center was very small (probably less than 1%) or nil, over most of the range of ventilation rate (roughly 12 L s^-1 to 48 L s^-1 per person). However, there is some evidence of worker performance improvements of 2% or more when the indoor CO₂ concentration exceeded the outdoor concentration by less than 75 ppm.