In order to meet the latest government legislation ALL APPLIANCES within your workplace need to be tested and tagged regularly to adhere to Occupational Health & Safety Regulations, and comply with the current Australian Standards AS/NZS 3760: 2003.
Every place of work is different and so is the frequency of testing, it all depends on the environment in which the appliance is being used. There might be a few different environments in one workplace, so some appliances might need to be tested every 3 months if they are used in harsh surroundings.
However, if the appliance is used in a clean well maintained office for example,
the retest dates may extend to a period of up to 5 years.