60950 clause 4.3.12 可燃液体测试问题
60950－1中的4.3.12条要求对可燃气化物浓度进行取样检测，要求在设备周边环境中，浓度不大于其爆炸限值的50％，在点燃源附件不大于爆炸限值的25％。现有一喷码机，使用丁酮墨水，需要按此条检测，疑问是，标准中只说在正常使用下，那么检测应该在多大房间内进行？是通风还是密闭？因为喷码机销售后在实际使用中按照使用者的环境运行，多大房间，通风情况均不确定，有其他相关标准有规定吗？
附上标准章节：
4.3.12 Flammable liquids
If a flammable liquid is used in equipment, the liquid shall be kept in a closed reservoir,
except for the amount needed for the functioning of the equipment. The maximum quantity of
flammable liquid stored in an equipment shall in general be not more than 5 l. If, however, the
usage of liquid is such that more than 5 l is consumed in 8 h, it is permitted to increase the
quantity stored to that required for an 8 h operation.
Oil or equivalent liquids used for lubrication or in a hydraulic system shall have a flash point
of 149 °C or higher, and the reservoir shall be of sealed construction. The system shall have
provision for expansion of the liquid and shall incorporate means for pressure relief. This
requirement is not applicable to lubricating oils that are applied to points of friction in
quantities that would contribute negligible fuel to a fire.
Except under conditions given below, replenishable liquids such as printing inks shall have a
flash point of 60 °C or higher, and shall not be under sufficient pressure to cause atomization.
Replenishable flammable liquids that have a flash point of less than 60 °C or that are under
sufficient pressure to cause atomization are permitted provided inspection shows that there is
no likelihood of liquid sprays or build-up of flammable vapour-air mixtures that could cause
explosion or create a fire hazard. Under normal operating conditions, equipment using a
flammable liquid shall not generate a mixture with a concentration exceeding one quarter of
the EXPLOSION LIMIT if the mixture is in proximity to an ignition source, or exceeding half the
EXPLOSION LIMIT if the mixture is not in proximity to an ignition source. The investigation shall
also take into account the integrity of the liquid handling system. The liquid handling system
shall be suitably housed or constructed so that risk of fire or explosion is reduced, even under
the test conditions specified in 4.2.5.
Compliance is checked by inspection and, where necessary, by the following test.
The equipment is operated in accordance with 4.5.2 until its temperature stabilizes. In this
condition, the equipment is operated in a normal manner, as directed in the operating
instructions, and samples of the atmosphere in the vicinity of the electrical components and
around the equipment are taken to determine the concentration of flammable vapours present.
Samples of the atmosphere are taken at 4 min intervals; four samples to be taken during
normal operation, then seven samples after the equipment has stopped.
If, after the equipment has stopped, the concentration of flammable vapours appears to be
increasing, samples shall continue to be taken at 4 min intervals until the concentration is
shown to be decreasing.
If an abnormal operation of the equipment is possible with any of its fans not running, this
condition is simulated during this compliance test. 这个在标准是没有明确规定，所以只是我们只是需要理解“正常使用下”，按照正常理解是你所列举的情况都可以的，但是做内部设计认证最好按照最严酷等级来进行，做实验室认证，一般有专门实验室，没有特殊要求，看是否按照常规情况进行！
这个只是理解，仅仅参考，没有其他意思！ 引用第0楼someone于2007-07-13 18:12发表的 60950 clause 4.3.12 可燃液体测试问题 :
60950－1中的4.3.12条要求对可燃气化物浓度进行取样检测，要求在设备周边环境中，浓度不大于其爆炸限值的50％，在点燃源附件不大于爆炸限值的25％。
现有一喷码机，使用丁酮墨水，需要按此条检测，疑问是，标准中只说在正常使用下，那么检测应该在多大房间内进行？是通风还是密闭？因为喷码机销售后在实际使用中按照使用者的环境运行，多大房间，通风情况均不确定，有其他相关标准有规定吗？
附上标准章节：
.......
这个问题好偏，做了这么多年的60950，第一次见到这个问题。。。
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