Why is the production, sale and use of clay fiberglass strictly prohibited?

Clay fiberglass has extremely poor water resistance and serious performance defects. The production and use of clay fiberglass can easily cause safety hazards. Therefore, as early as 1999, clay fiberglass was included in the "Catalogue for Eliminating Backward Production Capacities, Technologies and Products" by the former State Economic and Trade Commission. Since then, it has been included in various editions of the "Guidance Catalog for Industrial Structural Adjustment" and "Fiberglass Industry Access Conditions" Zhongjun expressly prohibits the production, sale and use. The association has also organized or participated in special operations to eliminate, investigate and crack down on high-alkali fiberglass (ceramic fiberglass) on many occasions, and achieved certain results. However, due to the simple drawing process of clay crucibles, low equipment investment, and small floor area, and in recent years, it has gradually moved to border areas and remote mountainous areas, making production more hidden, making the crackdown and elimination work more difficult.
Recently, as the production and sales of fiberglass are booming and the overall profit level of the industry continues to rise, clay fiberglass continues to develop in some areas, and some unscrupulous traders even apply clay glass fiber to some major engineering projects or export it to overseas markets. Ceramic fiberglass has serious performance defects. Once an accident occurs in related applications, it will definitely cause serious economic and social problems.