What is the difference between an N95 and a P2 respirator?

N95 and the P2 respirators are essentially the same type of half-face particulate respirators, which serve the same purpose.
    
These respiratory protective devices are intended to protect the wearer from airborne contaminants. The mask forms a seal over the mouth and nose to achieve efficient filtration of airborne particles. The mask must be fitted and adjusted correctly to your face to provide the intended protection.
 
In the USA, the term N95 is used. These respirators are classified by NIOSH . In Australia, Australian/New Zealand Standard AS/NZS 1716:2012 Respiratory protective devices describes three classes of particulate filter, Class P1, P2 and P3. The P2 respirator is equivalent to the N95, however the testing requirements are slightly different. See fact sheet by 3M explaining the different specifications.

AS/NZS 1715:2009 Selection, use and maintenance of respiratory protective equipment requires fit-testing for respirators. Contact admin@safetyaction.com.au to arrange a fit test.
   
What is a Surgical mask?

A surgical mask is a loose-fitting, disposable device that creates a physical barrier between the mouth and nose. 

These masks are intended to protect others, not the wearer, from the wearer's saliva and respiratory secretions.

Provides some protection for the wearer from large airborne droplets.

Surgical masks are not capable of being fit-tested as there is no seal around the face, just loose fitting.

N95 Respirator

Surgical Mask