Tamilnadu Shops & Establishment Act

Dear All,
I am writing a policy on leave for one of my client based in Chennai. Anyone could help me out with Tamilnadu Shops & establishment act with respect to leaves.
I wud like to know hw many casual leaves, sick leaves and previlage leaves are allocated according to Tamilnadu Shops & Establishment Act.
Awiaitng for the response.
Regards,
Priya

CL-12 Available to employee from date of joining
SL-12 Available to employee from date of joining
PL- 12 As per company Policy

1.Casual Leave – 12day in a year
2.Sick Leave - 12day in a year
3.Earned Leave - 21days after completion of One year or 1 day for every20 working days
4.Maturnity Leave: Women employee with minimum 3 month of service can avail 12 weeks, can be extended 6week in case of serious illness.

I would like to know the calculation of earn leave as per shop & establishment act tamilnadu and number of earn leave minimum a concern should give.