PU514 3BSE013062R1控制系统
可能悬浮在足以产生可燃混合物的空气浓度中。在正常操作条件下，空气中存在危险浓度的I类场所连续、间歇或周期性存在。第2部分：处理、处理或使用危险浓度的场所，但通常位于封闭容器或封闭系统内，只有在意外破裂或故障时，这些场所才能逃离。A组含乙炔的环境。B组含有氢气或具有同等危险的气体或蒸汽（如人造气体）的环境。C组含有乙醚蒸汽、乙烯或环丙烷的大气。D组：含有汽油、己烷、石脑油、汽油、丁烷、丙烷、酒精、丙酮、苯甲醇、漆溶剂蒸汽或天然气的大气。E组含有金属粉尘的大气，包括铝、镁及其商业合金，以及具有类似危险特性的其他金属。F组含有炭黑、煤尘或煤饼粉尘的大气。G组含有面粉、淀粉或谷物粉尘的大气。典型的I类位置•炼油厂和汽油储存和分配区域。•将易燃液体用于零件清洗或其他操作的工业企业。•利用天然气和石油生产化学品的石化公司。•可能存在清洗液蒸汽的干洗厂。•在产品喷涂区域喷涂油漆或塑料的公司飞机库和燃料服务区公用气厂，以及涉及液化石油气或天然气储存和处理的操作。典型的II类位置•谷物升降机、面粉和饲料磨机。•制造、使用或储存镁铝粉末的工厂具有化学或冶金工艺的工厂、塑料、药品和木材等的生产商•淀粉或糖果的生产商香料研磨植物、糖植物和可可植物。
likely to be suspended in air concentrations sufficient to produce ignitable mixtures. Division I Locations which are hazardous concentrations in the air exist continuously, intermittently, or periodically under normal operating conditions. Division 2 Locations which are hazardous concentrations are handled, processed, or used but are normally within closed containers or closed systems from which they can escape only in case of accidental rupture or breakdown. Group A Atmospheres containing acetylene. Group B Atmospheres containing hydrogen, or gases or vapors of equivalent hazard, such as manufactured gas. Group C Atmospheres containing ethyl-ether vapors, ethylene, or cyclo-propane. Group D Atmospheres containing gasoline, hexane, naptha, benzine, butane, propane, alcohol, acetone, benzol, laquer solvent vapors, or natural gas. Group E Atmospheres containing metal dust, including aluminum, magnesium, and their commercial alloys, and other metals of similarly hazardous characteristics. Group F Atmospheres containing carbon black, coal or cake dust. Group G Atmospheres containing flour, starch, or grain dusts. Typical Class I Locations • Petroleum refineries and gasoline storage and dispensing areas. • Industrial firms that use flammable liquids in dip tanks for parts cleaning or other operations. • Petrochemical companies that manufacture chemicals from gas and oil. • Dry cleaning plants where vapors from cleaning fluids can be present. • Companies that have spraying areas where they coat products with paint or plastics. • Aircraft hangars and fuel servicing areas. • Utility gas plants, and operations involving storage and handling of liquified petroleum gas or natural gas. Typical Class II Locations • Grain elevators, flour, and feed mills. • Plants that manufacture, use, or store magnesium of aluminum powders. • Plants that have chemical or metallurgical processes, producers of plastics, medicines, and firewoods, etc. • Producers of starch or candies. • Spice-grinding plants, sugar plants, and cocoa plants.
