In power plants delivered by Wartsil the risk assessment methods used are Hazid, Hazop, LOPA, FMEA, FTA, FERA and QRA. The methods are chosen e.g. depending on the scope of supply for the project and customer requirements. In addition to these the EU product safety legislation is fulfilled by using EN ISO 12100 for machinery risk assessment. All the methods draw their own pictures of risks identified and ways to mitigate them. Only when all the pictures are united the risk reduction can be seen to be sufficient. Through these risk assessments the biggest risks for health, environment and asset are identified and mitigated with protective measures.
In the power plant delivery projects several stakeholders are involved whose requirements needs to be taken into account. The goal of the risk assessment used as well as its limits has to be clearly defined and streamlined through the process. One of the most important factors is the consistent risk evaluation. Hazop and LOPA has been done for Wartsil standard design by using Wartsil Risk Matrix. In delivery project the customer often wishes to use their own risk matrix and then project wise Hazop and LOPA's are done together with customer. The risk evaluation may become difficult, if there is a wish to use different evaluation methods by different parties. The risk assessment methods should be therefore agreed in the contract in detailed enough level.