Use the risk matrix below and probability figures for the situation:

• An organisation has Oil Ring Main Unit switchgear that has been poorly maintained due to lack of spares and has a probability of failure during operation of 1 in 100. 
• The switchgear is only operated occasionally (on average once a year). 
• The operation is manual with the operator standing in front of the switchgear. 
• The consequence of the switchgear failure is explosion of the tank, arc fault, projectiles, oil spillage and possible fire.
• The cost to replace the switchgear is estimated to be $100,000. 

 

1. Determine the risk level (low/medium / high / very high). 
2. Indicate whether proactive replacement of this switchgear before failure occurs is preferred or not. 
3. State any assumptions made for the basis of your determination.

 

Probability:

• Almost certain – 1 in 10
• Likely – 1 in 100
• Possible – 1 in 1000
• Unlikely – 1 in 10000
• Rare – 1 in 1000000