This chapter is from the book
This chapter is from the book
This chapter is from the book
Safety Practices
- Summarize safety practices.
New to this version of the Network+ exam is objective 5.6: Summarize safety practices. This topic has always existed within the CompTIA A+ objectives, and will be familiar to those who already hold that certification, but it has not previously been tested on the Network+ exam.
Focusing on Safety
When working with anything, it is important to know the potential safety hazards, how to address them, and how to avoid them. It is imperative that you understand such issues as material safety data sheets (MSDSs) and know how to reference them when needed. Any type of chemical, equipment, or supply that has the potential to harm the environment or people has to have an MSDS associated with it. These are traditionally created by the manufacturer, and you can obtain them from the manufacturer or from the U.S. Environmental Protection Agency at www.epa.gov. These sheets are not intended for consumer use, but are aimed at emergency workers and employees who are exposed to the risks of the particular product. Among the information they include are such things as boiling point, melting point, flash point, and potential health risks. They also cover storage and disposal recommendations, and the procedures to follow in the case of a spill or leak.
HVAC (heating, ventilating, and air conditioning) is one of the biggest expenses for a building. Many companies market scheduling and monitoring software that can help reduce HVAC costs and increase efficiency as well as increase safety. Heat recovery ventilation (HRV) uses equipment known as heat exchangers to move fresh air into buildings that are adequately insulated without causing all the conditioned air to be lost. When HRVs also condition for humidity, they fall into the category of energy recovery ventilators (ERVs).
Electrical Safety and ESD
One of the most dangerous components when working with computers is electricity. Electrostatic discharge (ESD) occurs when two objects of dissimilar electrical charge come in contact with each other; the charge can damage electronic components and humans as well. Proper ESD precautions include wearing an antistatic wrist strap and properly grounding yourself.
Grounding equipment also crucial to safety. A dedicated ground (traditionally signified by an orange electrical outlet) prevents a discharge from any other device from damaging this one.
Installation Safety
Common sense is the best tool you have when it comes to installation safety. If lifting heavy boxes or equipment, be sure to bend at the hips when lifting and get enough people to assist to keep from anyone getting hurt. Place equipment in appropriate spaces and follow all installation rules/guidelines (particularly with items such as racks). Understand the purpose for the tools you use and use them for that purpose; don’t use a screwdriver as a chisel, for instance. Although it might take longer to do something correctly, it increases safety when you do.
Fire Suppression
Fire suppression is a key consideration in computer-center design. Fire suppression is the act of actually extinguishing a fire versus preventing one. Two primary types of fire-suppression systems are in use: fire extinguishers and fixed systems.
Fire Extinguishers
Fire extinguishers are portable systems. The selection and use of fire extinguishers is critical. Four primary types of fire extinguishers are available, classified by the types of fires they put out: A, B, C, and D. Table 6.8 describes the four types of fires and the capabilities of various extinguishers.
TABLE 6.8 Fire Extinguisher Ratings
Type |
Use |
Retardant Composition |
A |
Wood and paper |
Largely water or chemical |
B |
Flammable liquids |
Fire-retardant chemicals |
C |
Electrical |
Nonconductive chemicals |
D |
Flammable metals |
Varies, type specific |
Several multipurpose types of extinguishers combine extinguisher capabilities in a single bottle. The more common multipurpose extinguishers are A-B, B-C, and ABC.
The recommended procedure for using a fire extinguisher is called the PASS method: pull, aim, squeeze, and sweep. Fire extinguishers usually operate for only a few seconds. So, if you use one, make sure that you don’t fixate on a single spot. Most fire extinguishers have a limited effective range of from 3 to 8 feet.
Most fire extinguishers require an annual inspection. This is a favorite area of citation by fire inspectors. You can contract with services to do this on a regular basis: They will inspect or replace your fire extinguishers according to a scheduled agreement.
Fixed Systems
Fixed systems are usually part of the building systems. The most common fixed systems combine fire detectors with fire-suppression systems, where the detectors usually trigger either because of a rapid temperature change or because of excessive smoke. The fire-suppression system uses either water sprinklers or fire-suppressing gas. Water systems work with overhead nozzles, and these systems are the most common method in modern buildings. Water systems are reliable, relatively inexpensive, and require little maintenance.
The one drawback to water-based systems is that they cause extreme damage to energized electrical equipment such as computers. These systems can be tied into relays that terminate power to computer systems before they release water into the building.
Gas-based systems were originally designed to use carbon dioxide and later Halon gas. Halon gas is not used anymore because it damages the ozone layer; environmentally acceptable substitutes are now available, with FM200 being one of the most common. The principle of a gas system is that it displaces the oxygen in the room, thereby removing this necessary component of a fire.
Special ventilation systems are usually installed in gas systems to limit air circulation when the gas is released. Gas systems are also expensive, and they’re usually implemented only in computer rooms or other areas where water would cause damage to technology or other intellectual property.
In Case of an Emergency
Regardless of the planning and precautions in place, sometimes accidents happen. When they do, it is important to have emergency procedures in place for dealing with them. You should have a layout of the building handy that can be referenced in case the building must be evacuated and have a fire escape plan that all employees are aware of. Make sure that they know the safety/emergency exits and you have a working emergency alert system in place.
Make sure that when your systems fail, they do so appropriately. The two methods of responding to failure are to fail open or fail closed. Failing open means that things are essentially left as they are when the problem occurs, and failing closed means that systems are shut down when the problem is encountered. The correct response depends on the situation and the types of systems you are working with.
Cram Quiz
Which government agency can you turn to in order to find MSDS sheets?
A. FTC- B. FCC
- C. EPA
- D. FDA
Which of the following type of fire extinguisher is marketed for use with cooking oil fires?
- A. K
- B. C
- C. D
- D. A
Which of the following is a major drawback to gas-based extinguisher systems?
- A. They must be recharged on a weekly basis.
- B. They are not available within the United States.
- C. They rely on operators to activate.
- D. They require sealed environments in which to operate.
Cram Quiz Answers
- C. MSDS sheets are created by the manufacturer and can be obtained from them or the EPA (Environmental Protection Agency).
- A. Type K fire extinguishers are marketed for use with cooking oil fires. These are a subset of Type B extinguishers.
- D. The major drawback to gas-based systems is that they require sealed environments to operate.