21区：正常运行时，很可能偶然地以空气中可燃性粉尘云形式存在于爆炸性环境中的场所。 在大多数情况下，21区范围可通过与形成爆炸性粉尘／空气混合物环境有关的释放源的评价来 规定。

What is a Zone 21 hazardous area? A Zone 21 area is classified as a place in which an explosive atmosphere consisting of a mixture with air or flammable substances in the form of powder or dust is likely to occur in normal operation occasionally.

Once flammability is established, zoning is determined following the grade of release: continuous grade of dust release is zone 20; primary grade of dust release is zone 21; secondary grade of dust release is zone 22. In certain circumstances, the zoning may be modified to accommodate dust cloud concentrations known to exist inside plant equipment.

Zone 0 or 20 is for environments where an explosive atmosphere is constantly present, such as inside a tank. Zone 1 or 21 applies if an explosive atmosphere is present only intermittently.

2018年10月19日 · 北美地区 (UL) –在危险环境中，电器设备产品的使用与安装，须符合美国电工法规 (NEC®) 条文 500-506 的要求;同时还会有主管机关 (Authority Having Jurisdiction, AHJ) 到现场进行稽核。 国际电工防爆认证系统 (IECEx) –认证的宗旨是建立防爆产品国际认证体系，实现防爆产品在审核上有统一标准、证书及标志，并可透过多国转证的机制，让符合规范的产品得以迅速进入各国市场，进而促进国际贸易。 在 IECEx体系下，仅接受认可的认证机构 (ExCB) 和检验实 …

2017年8月30日 · 21区：在正常运行过程中可能出现的粉尘数量足以形成可燃性粉尘与空气混合物但未划入20区的场所。 22区：在异常情况下，可燃性粉尘云偶尔出现并且只是短时间存在、或可燃性粉尘偶尔出现堆积或可能存在粉尘层并且产生可燃性粉尘空气混合物的场所。

In a hazardous dust environment, an ATEX Zone 21 is classified as an area that is classified ‘as a place in which an explosive atmosphere in the form of a cloud of combustible dust in the air is likely to occur occasionally during normal operation’ whereas an ATEX Zone 22 is classified as 'a place in which an explosive atmosphere in the ...

在危险的粉尘环境中，ATEX 21区被归类为一个区域，该区域被分类为“在正常运行期间偶尔可能发生空气中可燃粉尘云形式的爆炸性环境”的区域，而ATEX 22区被归类为“在正常运行中不太可能发生空气中可燃粉尘云形式的爆炸性气体的地方，但如果确实发生，它将在短时间内出现只要’。 在任何ATEX额定区域内，安全性都非常重要，防爆伺服电机和防爆设备的必要性至关重要。 杭州摩森机电 防爆伺服电机 设计用于许多不同的行业，包括食品行业，石油化工，天然气行业和其 …

2021年6月15日 · 根据可燃性粉尘/空气混合物出现的频率和持续时间及粉尘层的厚度进行分类，可分为20区、21区和22区。 20区： zone 20，在正常运行过程中可燃性粉尘连续出现或经常出现，其数量足以形成 可燃性粉尘 与空气混合物和/或可能形成无法控制和极厚的粉尘层的场所及容器内部。 21区： zone 21，在正常运行过程中，可能出现粉尘数量足以形成可燃性粉尘与空气混合物但未划入20区的场所。 该区域包括与充入排放粉尘点直接相邻的场所、出现粉尘层和正常操 …

Zone Nature and Probability of Hazard Material; Zone 20: An area where combustible dusts or ignitable fibers and flyings are present continuously or for long periods of time. Zone 21: An area where combustible dusts or ignitable fibers and flyings are likely to occur under normal operating conditions. Zone 22