为了加快新型建材的发展和应用步伐,提高建材产品的档次和质量,北京市建委于1998年和1999年分别公布了两批限制使用和淘汰的23种落后建材产品。经过两年多的实践,取得了一定的成效。目前,市建委公布了第三批在2001年10月1日执行淘汰和限制使用的落后建材产品。图示如下: In order to speed up the development and application of new building materials and improve the grade and quality of building materials, the Beijing Construction Commission announced in 1998 and 1999 two batches of 23 backward construction materials that were restricted from use and eliminated. After more than two years of practice, we have achieved certain results. At present, the municipal construction commission announced the third batch of backward building materials products that were eliminated and restricted for use on October 1, 2001. The illustration is as follows: