Hi,

I was wondering if my comma use in the following sentence is correct:

Because safety of our staff and guests is our main concern, and to comply with government regulations, we are ceasing operations until these vital systems can function properly.

The first comma is used after an introductory clause, but why did I use the second comma?  Could the second clause be consiedered dependent, eliminating the need for the second comma, or is the comma still necessary because the main clause comes after the dependent clause? 

The sentence consists of four parts: (a subordinate clause) (an adverbial phrase) (a main clause) (a subordinate clause).

Because of their different structures, it's good to use a comma to separate the first part from the second part. You need to use a comma to separate the main clause from what comes before it.

Could it be re-written?

Because safety of our staff and guests, and complying with government regulations are our main concerns, we are ceasing operations until these vital systems can function properly. No, this is terrible.

Also, would guests require an apostrophe to show plural ownership in the previous case, and in the example below? When you say 'of', you shouldn't also use the apostrophe form.

...safety of our staff and guests'...
              OR
...guests' experiences...

Best wishes, Clive