Kong Ming commands Qin Qiong
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This post was last edited by flute6 on 2016-7-25 at 12:18. The technicians mentioned the conditions under which alarms for flammable and toxic substances should be activated. Some people said that according to the appendix of TSG D0001-2009, the Technical Regulations for Safety Inspection of Pressure Pipelines – Industrial Pipelines, regarding the method for calculating the toxicity of mixtures, one of the components is considered to have low toxicity; therefore, there is no need for a toxic substance alarm. Yuan Fang, what do you think?
For example, if the hydrogen sulfide content in the standard gas used is around 10 ppm, then the concentration of hydrogen sulfide that leaks into the site will not exceed 10 ppm; it becomes even lower after dilution, so it makes sense to consider it a minor hazard
There’s some truth to that; otherwise, how would it be calculated?
Assuming the hydrogen sulfide concentration is around 11 mg/m3 and the other components are non-toxic, with an LC50 of 618 mg/m3 (for inhalation in rats), the mixture should be considered to pose a mild hazard based on toxicity calculations. Should an alarm be set up?
This requires some maneuvering. Assuming the hydrogen sulfide concentration is 100 ppm, and based on the ventilation conditions at the site, if it can be calculated that the concentration after dilution due to leakage is less than 10 ppm, then explaining this to the safety assessment experts increases the chances of approval significantly, provided the relationship with them is good
There is no need to set up a fixed alarm. Portable alarms can be purchased and carried when entering this area; several areas can share them.