Protection against residual voltage

Live parts having a residual voltage larger then 60V after disconnecting supply mains must be discharged to 60V under 5 seconds after the disconnection of the supply mains.

In the case of plugs or similar devices in which the withdrawal results in an exposure of conductors, the discharge time must not exceed 1 second.

Use the following formula:

$$Vc=V\times e^{-t/Tau}$$

Vc: Capacitor voltage.
V:   Start voltage on capacitor.
R:   Resistor.
τ:   Tau is the time constant τ = R x C in seconds.
t:    time in seconds from V to Vc.

Remember to read the prober standard to be 100% sure of what to do (like 60204-1).