Investigation And Evaluation Of Indoor Environment In Existing Library Buildings In Xi'an

With the great development of economy and the popularity of higher education, universities have more and more students who are wondering to know the condition of indoor environment of their life and study which is very important to their health. Library is an important place to students. But there are many problems because of the large stream of people and the great many books of storage and the ill decoration and the poor ventilation system and the unsuitable address. These problems are noise, non-ventilation, contaminated air, off-flavor air, unreasonable spatial arrangement and deficit greening. So people should pay more attention to indoor environment of libraries at present.The paper discusses the development background of research of indoor environment of libraries. Review the possible contaminations in libraries and their possible sources and their possible harmfulnesses to people. The objects of the study are seven libraries in Xi'an city. The indoor environmental characteristics of the library are thermal environment, visual environment, aural environment, air environment and spatial environment. Date related to temperature, relative humidity, HCHO, PM₁₀, TVOC and Rn₂₂₂ were measured and evaluated. The results disclose that the thermal environment and indoor air environment are not satisfaction. People need to do more work to improve them. At the same time, a questionnaire which aimes to evaluate the opinions and observations of users was prepared in college libraries. Readers feel least satisfaction about relative humidity, ventilation and greening. The paper gives the coefficient of correlation between factors and indoor environment by correlation analysis. The coefficients of correlation of relative humidity, ventilation, greening are not maximum, but contaminated air's and off-flavor air's are the forehand. The results also display that every factor is coherent with other factors. So every factor is not independence and there are excessive factors. Simultaneity, sum up the subjective evaluation and the coefficients of correlation of factors and show up the the result directly by radar map. And comparing the subjective evaluation with objective evaluation of the indoor air environment, there are big differences between each other.In research, writer finds that the factors readers feeling worst are nonsignificant to affect reader'evaluation. In order to know the relative weights of the factors of subjective survey contributing to the overall satisfaction, to discover the most important index, and to disclosure the correlation between improvement and satisfaction about indoor environment of libraries, the paper use a model and proposes a method to determine objective weights of indoor environment quality based in rough set. By comparing the weights, the factors of contaminated air, bad spatial allocation plan and off-flavor air are the important contributors to overall dissatisfaction, while the factors of temperature, cleanness and blowed feeling may be reduced firstly to simplify evaluation system because of their meeting readers' need. This suggests that an improvement in air quality and spatial allocation plan would yield a considerable improvement in overall satisfaction.It's difficult to survey radon, so the investigation of the indoor pollution of radon in a university of Xi'an has been carried independently. The indoor radon level in the university is 24 hours uninterruptedly determined upon-the-spot. Radon concentration in 30 room range from 11.1 -218.3 Bq/m³ with an overall arithmetic mean value of 60.68 Bq/m³, and the max concentration is 218.3 Bq/m³. The influence factors of indoor radon level are fitment degree, ventilation and building shape. Deleterious fitment material and poor ventilation are vital reasons which lead to ascendence of the radon concentration. We should attach the importance of the hazardous affect of indoor radon.