Subsystem/system hazard analysis worksheet

Figure 7.4 Elevator plunger subsystem/system hazard analysis worksheet...

Figure 8-4 Subsystem/System Hazard Analysis Worksheet.

Figure 7.1 Sample subsystem/system hazard analysis (SSHA) worksheet.

Worksheets are normally not required. If the complexity of the change dictates the use of worksheets, use the system/subsystem hazard analysis worksheet format depicted earlier in Figure 8-4. 

Figure 11.1 shows an example of a fault hazard analysis worksheet that can be modified to a specific system or subsystem. An explanation of each column on the worksheet is also provided. 

FMEA is a very methodical tool that looks at every component in the system (or subsystem) under study and then identifies the ways the component can fail (failure modes). Each failure mode is further analyzed to determine what would be the effects of that particular failure mode on the system. Results are posted in tabular form (very similar to the hazard analysis worksheet). 

The information recorded on the PHA worksheet, together with the PHA report, will greatly facilitate the performance of other benehcial system analyses (such as the subsystem hazard analysis, the failure mode and effect analysis, and the operating and support hazard analysis) that may be accomplished during the remaining phases of the product life cycle. 

Figure 7.4 is the SSHA worksheet, completed to show the analysis of the two conditions discussed in this example. Additional evaluation can occur regarding the elevator system, with concentration on other possible hazardous conditions associated with other elevator subsystems and components. 

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