Besides your standard entry door, you will most likely be required to have at least one additional emergency exit door.  Requirements for emergency doors are based both on the building codes in your city and the maximum occupancy of your building.

Requirements for easy-open exit door locks came into effect around the beginning of the 20th century after multiple incidents of mass casualties from fires were caused when people could not quickly and easily leave the commercial building.

Emergency exit doors normally only work one way, going outward.  However, it is possible for managers to have keys made that allow you back in.  They exit door locks they use for opening are push bars, making them open quickly and allow for a faster exit.

Some doors, especially those designated as fire exits can be hooked up to alarm mechanisms that are triggered when the door opens.  This is a convenient and usually necessary feature to have, but can also cause problems if someone accidentally tries to open this door as a possible general exit.  Putting signs on the door can help, but this mistake can still happen sometimes.

Because this issue relies a lot on building code, your first consult for this part of your project should be with the planning commission for your town, county, or city.  They will provide the first set of guidelines you need for this project before you decide which exit door locks you need, be it panic locks, fire locks, or something different for your emergency exit doors.