I had posted a PPt some two years back which is still available in the Labour and Employees Relations forum of citehr and my blog (presently not found, I don't know why!)The ppt may give you a brief idea about what all laws are applicable to your establishments. I have revised it with latest amendments but I am not able to post it here due to some technical problems. Therefore, please bear with me, I shall post it later but try this link to get the ppt.
21st January 2010 From India, Kannur