Abstract: This paper introduces the historical background of the construction of anti freezing outdoor fire hydrant. Analyzed the possible defects in the design and construction of the outdoor ground fire hydrant in cold areas, and summarized the common product quality problems of the outdoor ground fire hydrant. Described the design and construction scheme of anti freezing outdoor fire hydrant, including the improvement measures for existing fire hydrant products, summarized the installation and application effect, and put forward the corresponding suggestions. 

Key words:  fire protection, antifreeze type, outdoor ground fire hydrant, automatic drain valve