曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
APPLICATION: Full application of MORT is reserved for the highest risks and most operation-critical
activities because of the time and expense required. MORT generally requires a specially trained loss
control professional to assure proper application.
METHOD: MORT is accomplished using the MORT diagrams, of which there are several levels
available. The most comprehensive, with about 10,000 blocks, fills a book. There is an intermediate
diagram with about 1500 blocks, and a basic diagram with about 300. It is possible to tailor a MORT
diagram by choosing various branches of the tree and using only those segments. The MORT is
essentially a negative tree, so the process begins by placing an undesired loss event at the top of the
FAA System Safety Handbook, Appendix F
December 30, 2000
F-41
diagram used. The user then systematically responds to the issues posed by the diagram. All aspects of
the diagram are considered and the “less than adequate” blocks are highlighted for risk control action.
RESOURCES: The best source of information on MORT is the System Safety Office.
COMMENTS: The MORT diagram is an elaborate negative Logic Diagram. The difference is primarily
that the MORT diagram is already filled out for the user, allowing a person to identify the contributory
factors for a given undesirable event. Since the MORT is very detailed, as mentioned above, a person can
identify basic causes for essentially any type of event.
EXAMPLES: The top blocks of the MORT diagram are displayed at Figure 1.3.5A.
Figure 1.3.5A Example MORT Section
Accidental
Losses
Oversights &
Omissions
Assumed
Risk
Operational System
Factors LTA
Management System
Factors LTA
2.0 RISK ASSESSMENT TOOLS, DETAILS, AND EXAMPLES
Introduction. This section contains an example of assessing risk, using a risk assessment matrix (Figure
2). The easiest way to understand the application of the matrix is to apply it. The reasoning used in
constructing the matrix in the example below is provided.
FAA System Safety Handbook, Appendix F
December 30, 2000
F-42
Example. The example below demonstrates the application of the matrix to the risk associated with
moving a heavy piece of machinery.
Risk to be assessed: The risk of the machine falling over and injuring personnel.
Probability assessment: The following paragraphs illustrate the thinking process that might be followed in
developing the probability segment of the risk assessment:
Use previous experience and the database, if available. “We moved a similar machine once before and
although it did not fall over, there were some close calls. This machine is not as easy to secure as that
machine and has a higher center of gravity and poses an even greater chance of falling. The base safety
office indicates that there was an accident about 18 months ago that involved a similar operation. An
individual received a broken leg in that case.”
Use the output of the hazard analysis process. “Our hazard analysis shows that there are several steps in
the machine movement process where the machine is vulnerable to falling. Furthermore, there are several
different types of contributory hazards that could cause the machine to fall. Both these factors increase
the probability of falling.”
Consider expert opinion. “My experienced manager feels that there is a real danger of the machine
falling”
Consider your own intuition and judgment. “My gut feeling is that there is a real possibility we could lose
control of this machine and topple it. The fact that we rarely move machines quite like this one increases
the probability of trouble.”
Refer to the matrix terms. “Hmmm, the decision seems to be between likely and occasional. I understand
likely to mean that the machine is likely to fall, meaning a pretty high probability. Certainly there is a real
chance it may fall, but if we are careful, there should be no problem. I am going to select Occasional as
the best option from the matrix.”
Severity assessment. The following illustrates the thinking process that might occur in selecting the
severity portion of the risk assessment matrix for the machine falling risk:
Identify likely outcomes. “If the machine falls, it will crush whatever it lands on. Such an injury will
almost certainly be severe. Because of the height of the machine, it can easily fall on a person’s head and
body with almost certain fatal results. There are also a variety of different crushing injuries, especially of
the feet, even if the machine falls only a short distance.
Identify the most likely outcomes. “Because of the weight of the machine, a severe injury is almost
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
System Safety Handbook系统安全手册下(99)
