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<h2 class="hd hd-2 unit-title">Component Redundancy</h2>
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<h2>7.2.1 Component Redundancy</h2>
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Describe the traditional approach to component reliability and explain the difference between "reliability" and "safety"" type="button" id="LD">MO 7.1</button></p>
<p>Prior to the advent of modern-day computers and software, safety was closely associated with hardware and the failure of components. The traditional approach to mitigating the consequences of hardware failure is to enforce component redundancy. In the following video, Prof. Hoffman builds a model of valves in series and in parallel to show how redundancy can help improve safety. However, as Dr. Thomas will explain, redundancy can also create new and unexpected problems.</p>
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<h2 class="hd hd-2 unit-title">Safety vs. Reliability</h2>
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<h2>7.2.2 Safety vs. Reliability</h2>
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<p>In colloquial language, safety and reliability are often used interchangeably. However, in the engineering context, they refer to two disparate concepts. Safety usually means making sure event X never occurs, whereas reliability typically means making sure event Y always occurs. Understanding this distinction is critical to our discussion about the various factors that contribute to system safety. As we will see in the next video, a particular situation can be both safe and reliable, neither safe nor reliable, or any combination of the two.</p>
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