We issued one policy, one manual and one set of procedures for 14001 and 18001, do you think It is better if (ISO) issues only one standard for both?

the same structure for the two standards, the same NO. of clauses, almost the same activities, but differand scope.

it's a matter of bussiness more than thing leads to improvement.

any standard dosn't evaluate the organization againest it's improvement and achieveing targets is just bussiness , so, as much as standards as much as bussiness

OHSAS18001 is a British standard and not part of the ISO family standards. But what’s the problem if integrated within the implementation and keep standards as it is 

Remember,18001 is not an ISO Standard

No, each standard should be separated than others, as every organization can slecect the suitable management standard for it is activity.

but for organization can build its management system as integrated system and i think it is usefull.

yes i thnk it can be include in ISO too coz it si littel changing jsut for diffrrent companies to makign money it does not effect on quality or quantity just game of documentation..if only one  complete comprihensive certificate be issued  may be more usefull and simple to implementation

No.

I agree with Mr. haitham shady answer