丁类厂房1. 对不燃烧物质进行加工，并在高温或熔化状态下经常产生强辐射

Category D plant <br>1. incombustible material processed, producing a strong and often produce radiant heat, spark or flame at a high temperature molten state or <br>2. or as a fuel gas, a liquid with a gas, liquid, solid fuel used for other various production <br>3. room temperature use or processing of the material is difficult to produce combustion

Ding plant<br>1. Processing of non-incendiary substances and often producing strong radiant heat, sparks or flames at high temperatures or melting<br>2. Various productions using gases, liquids, solids as fuel or combustion of gases and liquids for other purposes<br>3. Production of hard-burning substances used or processed at room temperature

Ding workshop<br>1. Processing of unburned materials and producing strong radiant heat, sparks or flames under high temperature or melting state<br>2. Various kinds of production using gas, liquid and solid as fuel or burning gas and liquid for other purposes<br>3. Production of using or processing refractory materials at room temperature<br>