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In today's industry, virtually every company relies on computers in its daily operation. Some companies are a computer-based service, such as a data base company, while others only rely on computers in certain branches of their operation, such as inventory control or accounting. Naturally, when a computer failure occurs, large business interruption and information loss can result. If the repairs to the computer are made immediately, this may leave very little explanation regarding how the failure occurred. Understanding how the loss occurred is important for insurance purposes.

Essentially, there are five sources of computer failure. These are:

• Electrical Malfunction

• Physical Impairment

• Water Damage

• Latent Defect

• Environmental Conditions

Electrical malfunctions occur when a computer is subjected to a higher voltage than expected. This can be caused by a surge in the power supply to the computer or from stray voltage such as lightning or static charge. To protect a computer from a voltage variation, it should be equipped with a surge protector. The results of high voltage in a computer are usually noticeable by visual examination. Computer chips on printed circuit boards may heat or their leads may melt. If this is observed, the cause of the failure is generally voltage-related.

Physical impairment refers to any damage resulting from the direct interaction between the computer and its surroundings. This could include damage during manufacturing, transit (i.e., shock damage, abuse, etc.), or any other physical disturbances.

Water can damage a computer when pipes burst or sprinklers are activated. Usually some protection for the computer is provided, however, it is seldom enough to stop the effects of large quantities of water. Once water enters the computer, stray voltages can arise which may make computer chips fail. Contaminated water, in particular, has the ability to conduct electric current. This occurs because the impurities in contaminated water tend to be conductive, or non-insulating.

The issue may arise as to the reliability of the computer after water damage. This relates to the long-term effect stray voltage has on a computer. The service life of various components could be seriously affected. In certain cases, the severity of the actual failure is an indication of the probability of reduced service life.

The most commonly misunderstood failure, as well as the most frequent type of failure, is the latent defect. This type of defect is associated with the production of the computer chips. In fact, the chips may appear to be in proper condition with no sign of physical or electrical damage. Each computer chip is produced with a reliability characteristic that depends on the method and quality of the manufacturing process. This characteristic is expressed in expected failures per billion device hours. A rating of four failures per billion device hours means that, if one billion chips were used, an average of four would fail in each hour. This demonstrates a basic characteristic of computer chips: They are subject to random failure. Therefore, when a computer is purchased, an associated reliability factor is also purchased.

Environmental conditions may cause a computer to fail in several ways. A rise in room temperature, an increase in humidity, or failure in the computer cooling system will cause an increase in the computer failure rate. To identify these factors, careful consideration must be given to the reported conditions prior to the failure. Many computers have emergency sensing systems and instructions which act in such circumstances to reduce the probability of these type of occurrences.

Computers can fail in many different ways. However, each will leave telltale signs. It is, therefore, important to recognize the signs of various modes of failure and their characteristics.

The information contained in this web site is intended for marketing purposes only. It is not all-inclusive, and does not fully describe the many and varied services that the company provides, nor does it completely describe the education, training, skills, or expertise of our staff.


Walters Forensic Engineering | 277 Wellington Street West, Suite 800 | Toronto, ON M5V 3H2
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