I am into the field of industrial safety for the last 10 1/2 years. Before that, I was involved in process equipment design. When, I joined safety department, I started reading about various topics in safety and one such topic is static electricity. For first few years, I had only book knowledge and no experience of what it is.
What already read in books is that static charge will be generated, when we
- comb our hair
- wear synthetic dress
- walk on wool carpets, etc
Following are my practical experiences
- when I approached TV, the hair on the forearm attracted to the picture tube
- After travelling, to get down, I tried to open the vehicle door by lifting the knob on door outside and I received shock
- my friend took out pen drive from his shirt pocket and when he inserted in the USB port, cracking sound came
- when I touched the monitor of desktop computer, I heard noise
- one night, I got up and went to bathroom for pressure relief. I saw some flash from my dhoti ( a cloth worn around instead of knickers / shorts ). I thought it is light reflection because of someone outside my apartment switched ON the light in his house or some vehicle light from ground floor. I had some fear also thinking it as some ghost, as a person died in the house above my house in the apartment block (though I don't believe, but a serious discussion on the issue before sleep with my family members and my denial of existence of ghosts made me to think that something of such sort is there). Then, next day while thinking about the flash in my dhothi, suddenly it occurred to me that my dhothi is synthetic and as it is in two layers, friction between layers might have caused charge accumulation and discharge in the form of flash. After reaching home from office, I waited for night and then closed window and door of my room, covered the window with thick curtain and blanket. Then, I took the same dhothi and rubbed fast and saw flashes generated. Then, I repeated the same and showed to my wife and children. The flashes were light green in colour. I don't know the reason for the colour of the flash, which I has to explore or search.
The last one narrated above is the one which I want to share with all and the lesson is that we should not wear synthetic dress when we work on or near flammable solvents / pyrophoric materials. The practical application of this information is that we should not wear synthetic dress when we go for petrol / gas filling. As we travel for sometime before we reach the pump, charge would have accumulated on the synthetic dress and it is likely that the discharge in the form of spark can initiate fire in the petrol pump station.