Often insurance companies suggest or require inspection once a year (often with little rationale, other than annual premiums are due).

Prudent facilities managers give special consideration to critical areas. One of our customers with a diverse level of risk has 3 frequencies of survey:

• Quarterly for critical areas where a failure might cost $100,000

• Annually for main switchboards, DBs and general facilities panels

• Three yearly for minor widespread aspects of their operation.

Another important consideration is winter or summer peak demands, or the amount of electrical loading being drawn at different times of the day.

Local environment (dust, temperature extremes, or corrosion) can affect when and how often to perform Thermography.

Another time to consider Thermography is when equipment has been replaced, rebuilt or recently commissioned. Even new equipment and installations may carry faults. Prudent managers will inspect new or modified equipment before acceptance.

When tenants "do their own Thermography" do you get a copy of the report? One of our customers found out the hard way when inadequate Thermography of a nationwide chain store failed to detect numerous faulty neutral conductors running over 175 degrees centigrade.

A more detailed explanation of these factors is included in a letter to a customer who was seeking Australian Standards for guidance.