危險場所劃分 Area classification
根據爆炸環(huán)境出現(xiàn)的頻率和持續(xù)的時間把危險場所劃分為不同的區(qū)域。
氣體場所分為三個區(qū)域：0區(qū)、1區(qū)和2區(qū)。
Hazardous areas are classified into zones based upon the frequency of the occurrence and duration of an explosive gas atmosphere.
The gas area is classified into three zones: zone0、zone 1 and zone 2.
0區(qū)
Zone 0
爆炸性環(huán)境中的爆炸混合物以氣體、蒸氣或薄霧形式連續(xù)出現(xiàn)或長時間存在的場所。
A place in which an explosive atmosphere consisting of a mixture with air of flammable substances in the form of gas, vapour or mist is present continuously or for long periods.
1區(qū)
Zone 1
在正常運行時，爆炸性環(huán)境中可能出現(xiàn)氣體、蒸氣或薄霧形式的爆炸性混合物的場所。
1區(qū)是防爆電氣設備的典型應用場所。
A place in which an explosive atmosphere consisting of a mixture with air of flammable substances in the form of gas, vapour or mist is likely to occur in normal operation occasionally.
2區(qū)
Zone 2
在正常運行時，爆炸性環(huán)境中不太可能出現(xiàn)氣體、蒸氣或薄霧形式的爆炸性混合物，如果出現(xiàn)也只是偶爾發(fā)生并且短
時間存在的場所。通常情況下，“短時間”是指持續(xù)時間不多于2個小時。
A place in which an explosive atmosphere consisting of a mixture with air of flammable substances in the form of gas, vapour or mist is likely to occur in normal operation occasionally but, if it dose occur, will persist for a short period only. As a rule, “for a short period only”means up to 2 hours.
粉塵場所分為三個區(qū)域：20區(qū)、21區(qū)和22區(qū)。
The dust area is classified as three zones：zone20、zone 21 and zone 22.
20區(qū)
Zone 20
在正常運行過程中可燃性粉塵連續(xù)出現(xiàn)或經常出現(xiàn)，其數量足以形成可燃性粉塵與空氣混合物和／或可能形成無法控制和極厚的粉塵層的場所及容器內部。
Area in which combustible dust, as a cloud, is present continuously or frequently, during normal operation, in sufficient quantity to be capable of producing an explosive concentration of combustible dust in mixture with air and / or where layers of dust of uncontrollable and excessive thickness can be formed.
21區(qū)
Zone 21
在正常運行過程中，可能出現(xiàn)粉塵數量足以形成可燃性粉塵與空氣混合物但未劃入20區(qū)的場所。該區(qū)域包括，與充入或排放粉塵直接相鄰的場所、出現(xiàn)粉塵層和正常操作情況下可能產生可燃濃度的可燃性粉塵與空氣混合物的場所。
Area not classified as zone 20 in which combustible dust, as a cloud, is likely to occur during normal operation, in sufficient quantities to be capable of producing an explosive concentration of combustible dust in mixture with air. This zone can include, among others, areas in the immediate vicinity of powder filling or emtying points and areas where dust layers occur and are likely in normal operation to give rise to an explosive concentration of combustible dust in mixture with air.
22區(qū)
Zone 22
在異常條件下，可燃性粉塵云偶爾出現(xiàn)并且只是短時間存在、或可燃性粉塵偶爾出現(xiàn)堆積或可能存在粉塵層并且產生可燃性粉塵空氣混合物但未劃入21區(qū)的場所。如果不能保證排除可燃性粉塵堆積或粉塵層時，則應劃分為21區(qū)。
Area not classified as zone 21 in which combustible dust clouds may occur infrequently and persist for only a short period, or in which accumulations or layers of combustible dust may be present under abnormal conditions and give rise to combustible mixtures of dust in air. Where, following an abnormal condition, the removal of dust accumulations or layers cannot be assured, then the area is to be classified zone 21.
