540 ppm
high ventilation kept indoor CO₂ near outdoor-equivalent levels
High ventilation maintained CO2 at 540 ppm
In a laboratory simulation of a modern open-plan office, Condition A used an outdoor air flow rate of 28.2 l/s per person, resulting in a CO2 level of 540 ppm. This served as the clean-air baseline against which the low-ventilation condition was compared.
In Condition A, outdoor air flow rate of 28.2 l/s person (CO2 level 540 ppm) was applied and in Condition B, outdoor air flow rate was 2.3 l/s person (CO2 level 2260 ppm).
Related findings
drivers reported higher mental effort at 1800 ppm CO₂ than at 800 ppm
Moderate CO2 elevation (1800 ppm) increases perceived effort in drivers compared to lower CO2 (800 ppm)
Chao Wang et al., 2023, The Science of The Total Environment
bioeffluents at high CO2 reduced cognitive performance on a cue-utilization test
Bioeffluent exposure at 3000 ppm CO2 reduced performance on a cue-utilization cognitive test
X. Zhang et al., 2017, Indoor Air
bioeffluents at high CO2 significantly raised salivary α-amylase, a stress marker
Bioeffluent exposure at 3000 ppm CO2 significantly increased salivary α-amylase compared with pre-exposure levels
X. Zhang et al., 2017, Indoor Air
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