Using the CGT-7100 to Measure the Indoor Ventilation Rate —Model Experiment with CO2 as Indicator—

User Benefits

- Non-dispersive infrared absorption spectrophotometry by ratio photometry achieves excellent measurement value stability. - Offers both the portability and simplicity essential for workplace measurements. - Acquired data can be stored on a USB flash drive for easy editing on a computer or sharing with other departments.

Introduction

From the perspective of preventing infectious diseases, gas poisoning accidents, and improving the working environment, there has been rapidly growing interest in regularly exchanging the air in indoor spaces and vehicle interiors. Two methods are widely used to determine ventilation rates based on measuring CO₂ as a tracer gas. The CO₂ concentration decay method determines the exchange rate based on how much indoor CO₂ concentration levels decrease over time due to ventilation measures, whereas the constant CO₂ concentration method determines the ventilation rate based on the amount of CO₂ that must be generated within a room to maintain a constant concentration. For this experiment, the CO₂ concentration decay method was used with a glovebox as a model for simulating room air to demonstrate the utility of CGT-7100 transportable gas analyzers for measuring indoor ventilation rates. Given a starting CO₂ concentration inside the glovebox that is higher than in the external air, when ventilation is started, the external air flowing into the glovebox dilutes CO₂ to gradually decrease the concentration level. The CGT-7100 determines the ventilation rate by measuring that concentration change.

June 29, 2021 GMT