The rule came into effect this week, and will be enforced as long as the authorities feel it is necessary to drum into soldiers that official working hours have to be taken seriously.
According to the army there is nothing controversial about the rule, and that it was definitely time to crack the whip.
The new regulation followed increasing complaints of nobody being in the office on especially Wednesday and Friday afternoons.
Employees have reportedly been abusing a long-standing rule in the army that allows soldiers who officially practice sport to leave with a "sport pass".
Most of the people who leave on a Wednesday afternoon do not take part in any kind of sport, it was established.
The three building exits are being locked in the morning and reopened at 16:00.
At 16:00, Beeld reported, there is a frantic stampede to get to the gate first, to avoid the long queue at the exit, where employees are delayed while guards search each car to combat theft of government property.