I am not certain about your office, but most dining halss use a 6 oz. ladel, with 2 oz. being roughly requivalent to one whole egg. You can do a search on fitday.com to get a better macro/calorie breakdown of eggs or whites by the oz.
Again, I'm not certain about the exact amount in your particular office, though. The easiest thing to do is just ask the server what size ladel they are using. Hope this helps.