Dear Cutinha,
PL means privileged leave. CL means casual leave. SL stands for sickness leave. As per the Factories Act of 1948, the employer must provide leave (regardless of the name). An employee can take one leave for every twenty working days of the previous year, which amounts to 15 days. Now, let me explain how.
There are a total of 365 days in a year. If you deduct 52 days for weekly offs and 8 paid holidays, only 300 days remain. If we divide 300 by 20, you will get 15, which is the minimum number required as per the Factories Act.
I hope all doubts are cleared.
Siba