Would you please help in finding best practices or standards pertaining to lubeoil storage and compressed gas cylinder storage requirements? Thanks in advance.

Much depends on quantities etc and advice will vary from country to country, (I note you are in the Middle East), however try looking on the internet for information from sources such as DEFRA for Guidance on the Control of Pollution (oil storage) Regs, the Environment Agency for PPG2, Calor Gas for their code of practice for storage of full and empty LPG bottles. There is also a significant amount of information on the Health and Safety Executive's website. Whilst these will largely be specific to the UK they may point you in the right direction.