Cultural heritage is an irreplaceable and non-renewable resource for human history. In 2002, change in the appearance of collections was observed, thought to be caused by environmental change, air pollution, and bio-deterioration. In GanSu and QingHai Provinces, 10% and 14% of museum collections showed evidence of damage.

Key Lab of Aerosol Chemistry & Physics (KLACP), Institute of Earth Environment, Chinese Academy of Sciences (IEECAS) dedicate to indoor air quality in site museums in China since 2002. After several monitoring campaign, a long-term IAQ database was firstly established in Emperor Qin’s Terra-Cotta Museum (QTM). Weathering of material was observed on the outer part of the terra-cotta statues. Fluctuations of indoor temperature and relative humidity, and high concentrations of acidic aerosols inside Pit No.1 were found, which could have adverse effects on the statues.

In 2015, KLACP analyzed results of long-term measurements from 1989 to 2013 to evaluate the effectiveness of controls in the Museum (Li et al., 2015). Decreased indoor particulate matter mass was achieved, indicating the benefits from energy innovation and relocations of parking lots, factories, and residential dwellings in the surrounding area. With the increased tourist flow and restoration work during the past 10 years, indoor activities are of increasing concerns in QTM Museum. 

Results of long-term measurements from 1989 to 2013, combined with environmental policies and indoor activities that can affect air quality

Supported by National Geographic Air and Water Conservation Fund (Facing air pollution: dangerous to Chinese cultural heritage, GEFC29-15), further monitoring campaign will be deployed in 2016 to update the database. Technologies to evaluate IAQ in QTM were also transferred to other on-site museums in China (Hu et al., 2015). Preliminary researches adopted at five site museums of Yangtze River civilization has found that besides short-term fluctuation and seasonal variation in microclimate conditions, infiltration of gaseous and particulate air pollutants should be of increasing concern at museums in Southern China. 

The penetration of fine particulate matters at all site museums posed potential physical and chemical hazards to indoor materials.

Tafeng Hu, Wenting Jia, Junji Cao, Rujin Huang, Hua Li, Suixin Liu, Tao Ma, Yuqing Zhu. 2015. Indoor air quality at five site museums of Yangtze River civilization. Atmospheric Environment. 123, 449-454.

Hua Li, Tafeng Hu, Wenting Jia, Junji Cao, Suixin Liu, Rujin Huang, Tao Ma, Na Xi. 2015. Evaluation of Policy Influence on Long-Term Indoor Air Quality in Emperor Qin’s Terra-Cotta Museum, China. Atmosphere. 6, 474-489.