How many Sittings Required in Laser Hair Treatment?

In laser hair removal treatment your hairs take 7 to 21 days to start falling out because of laser hair removal . 

This procedure uses high power pulsed diode laser on hair root . 
This laser light is absorbed by melanin in the hair shaft which is damaging the follicular epithelium. 
So this is the cause of permanent hair reduction . 
It is not happening in a single sitting hair shaft is damaging permanently in 7-30 days depend on your hair thickness and particular area of hair removal like arms pubic etc. for example if you give salty water ( low strength of salt ) in a plant then water damage roots of plant and plant will die in 7-30 days not at once. 
another example if you give highly concentrate salty water in a plant then plant root will damage in 2-24 hour but laser technician doesn't give such a high beam on your hair shaft due to side effects of laser hair removal ,So this is the reason that why you need many sittings In laser hair removal treatment.
 your hairs take 7 to 21 days to start falling out because they want to damage only hair roots and protect  the epidermis ( skin layer ).
Next:-What happen if anyone stopped laser hair removal in mid treatment?
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