After the ballot boxes are transported to the counting centre, candidates and their counting agents can inspect the boxes to ensure that they are still intact and that none of the seals have been broken or tampered with.

Once they are satisfied that the boxes have remained secure, the seals are broken and the ballot boxes opened. The ballot papers will be poured out, sorted and counted. 
Those present will also help to ascertain if the ballot boxes have been completely emptied. 

For more information on how the ballot boxes are transported to the counting centre, click here.

Source: ELD

This article is accurate as of Aug 2015.