Workers' awareness and indoor environmental quality in power-saving offices

The Great East Japan Earthquake on March 11, 2011 caused enormous damage to infrastructure and lead to a 15% peak-power reduction in and around Tokyo. The purpose of this study is to investigate changes in indoor environmental quality (IEQ) and subjective evaluations of IEQ. We conducted continuous field surveys and questionnaire surveys in five power-saving office buildings in the summers of 2011-2013. The results indicate that the thermal environment recovered to pre-quake levels after 2012; whereas, considering the lighting environment, desk level illuminance was greatly decreased from 750 lux (pre-quake) to around 500 lux (post-quake). Indoor air quality didn't change significantly. Nearly all of the workers are satisfied with IEQ today, but this differed with the workers' gender, age, awareness of saving electricity, and work satisfaction. In particular, differences in workers' awareness had a profound effect on their satisfaction with IEQ. This indicates that workers who were supportive of saving electricity experienced and reported greater satisfaction with IEQ.