Are my bitcoins safe in online wallet
www.blockchain.info for what happens on August 1?
I have my private keys & my account is fully secured.
I really need to know this

Probably not. Your coins were never safe with blockchain.info anyways since they continuously have security and usability issues anyways. If a chain split happens, you won't be able to decide on which chain you want to transact on, blockchain.info will choose that for you.
It is true that blockchain.info has had security and usability issues in that past, but unlike exchanges and other wallet sites, you have 100% control over your private keys.