Heating, air conditioning, and refrigeration mechanics and installers--often referred to as HVACR technicians--work on heating, ventilation, cooling, and refrigeration systems that control the air quality in many types of buildings.
Heating, air conditioning, and refrigeration mechanics and installers typically do the following:
Heating and air conditioning systems control the temperature, humidity, and overall air quality in homes, businesses, and other buildings. By providing a climate controlled environment, refrigeration systems make it possible to store and transport food, medicine, and other perishable items.
Although trained to do all three, HVACR technicians sometimes work strictly with heating, air conditioning, or refrigeration systems. They also may specialize in certain types of HVACR equipment, such as water-based heating systems, solar panels, or commercial refrigeration.
Depending on the task, HVACR technicians use many different tools. For example, they often use screwdrivers, wrenches, pipe cutters and other basic handtools when installing systems. To test or install complex system components, technicians may use more sophisticated tools, such as carbon monoxide testers, voltmeters, combustion analyzers, and acetylene torches.
When working on air conditioning and refrigeration systems, technicians must follow government regulations regarding the conservation, recovery, and recycling of refrigerants. This often entails proper handling and disposal of fluids.
Some HVACR technicians sell service contracts to their clients, providing regular maintenance of heating and cooling systems.
Other craft workers sometimes help install or repair cooling and heating systems. For example, on a large air conditioning installation job, especially one in which workers are covered by union contracts, ductwork might be done by sheet metal workers and duct installers, or electrical work by electricians. In addition, home appliance repairers usually service window air conditioners and household refrigerators. For more information on these occupations, see the profiles on sheet metal workers, electricians, or home appliance repairers.
Mechanical engineering technicians help mechanical engineers design, develop, test, and manufacture industrial machinery, consumer products, and other equipment. They may make sketches and rough layouts, record and analyze data, make calculations and estimates, and report their findings.
Mechanical engineering technicians typically do the following:
Mechanical engineering technicians also estimate labor costs, equipment life, and plant space. Some test and inspect machines and equipment or work with engineers to eliminate production problems. They may assist in testing products by, for example, setting up instrumentation for vehicle crash tests.
Line installers and repairers install or repair electrical power systems and telecommunications cables, including fiber optics.
Electrical power-line installers and repairers typically do the following:
Telecommunications line installers and repairers typically do the following:
Every time you turn on your lights, call someone on the phone, watch cable television, or access the Internet, you are connecting to complex networks of physical power lines and cables that provide you with electricity and connect you with the outside world. Line installers and repairers, also known as line workers or linemen, are the people who install and maintain these networks.
Line installers and repairers typically specialize, and the areas in which they specialize depend on the network and industry in which they work:
Electrical power-line installers and repairers install and maintain the power grid--the network of power lines that moves electricity from generating plants to customers. They routinely work with high-voltage electricity, which requires extreme caution. This can range from hundreds of thousands of volts for the long-distance transmission lines that make up the power grid to less than 10,000 volts for distribution lines that supply electricity to homes and businesses.
Line workers who maintain the interstate power grid work in crews that travel to work locations throughout a large region to take care of transmission lines and towers. Workers employed by local utilities work mainly with lower voltage distribution lines, maintaining equipment such as transformers, voltage regulators, and switches. They may also work on traffic lights and street lights.
Telecommunications line installers and repairers install and maintain the lines and cables used by local and long-distance telephone services, cable television, the Internet, and other communications networks. These services use different types of cables, including fiber-optic cables. Unlike metallic cables that carry electricity, fiber-optic cables are made of glass or plastic and transmit signals using light. Working with fiber optics requires special skills, such as the ability to splice and finish off optical cables. Additionally, workers test and troubleshoot cables and networking equipment.
Because these systems are so complicated, many line workers also specialize by duty:
Line installers install new cable. They may work for construction contractors, utilities, or telecommunications companies. They generally start a new job by digging underground trenches or putting up utility poles and towers to carry the wires and cables. They use a variety of construction equipment, including digger derricks, which are trucks equipped with augers and cranes used to dig holes in the ground and set poles in place. Line installers also use trenchers, cable plows, and directional bore machines, which are used to cut openings in the earth to lay underground cables. Once the poles, towers, tunnels, or trenches are ready, line installers string cable along poles and towers or through tunnels and trenches.
Line repairers are employed by utilities and telecommunications companies that maintain existing power and telecommunications lines. Maintenance needs may be identified in a variety of ways, including remote monitoring equipment, inspections by airplane or helicopter, and customer reports of service outages. Line repairers often must replace aging or outdated equipment, so many of these workers have installation duties in addition to their repair duties.
When a problem is reported, line repairers must identify the cause and fix it. This usually involves testing equipment and replacing it as necessary. To work on poles, line installers usually use bucket trucks to raise themselves to the top of the structure, although all line workers must be adept at climbing poles and towers when necessary. Workers use special safety equipment to keep them from falling when climbing utility poles and towers.
Storms and other natural disasters can cause extensive damage to networks of power lines. When a connection goes out, line repairers must work quickly to restore service to customers.
Assemblers and fabricators assemble both finished products and the parts that go into them. They use tools, machines, and their hands to make engines, computers, aircraft, toys, electronic devices, and more.
Assemblers and fabricators typically do the following:
Assemblers and fabricators have an important role in the manufacturing process. They assemble both finished products and the pieces that go into them. The products encompass a full range of manufactured products, including aircraft, toys, household appliances, automobiles, computers, and electronic devices.
Changes in technology have transformed the manufacturing and assembly process. Modern manufacturing systems use robots, computers, programmable motion-control devices, and various sensing technologies. These systems change the way in which goods are made and affect the jobs of those who make them. Advanced assemblers must be able to work with these new technologies and use them to produce goods.
The job of an assembler or fabricator ranges from very easy to very complicated, requiring a range of knowledge and skills. Skilled assemblers putting together complex machines, for example, read detailed schematics or blueprints that show how to assemble the machine. After determining how parts should connect, they use hand or power tools to trim, shim, cut, and make other adjustments to fit components together and align them properly. Once the parts are properly aligned, they connect them with bolts and screws or weld or solder pieces together.
Quality control is important throughout the assembly process, so assemblers look for faulty components and mistakes in the assembly process. They help to fix problems before defective products are made.
Manufacturing techniques are moving away from traditional assembly line systems toward lean manufacturing systems, which use teams of workers to produce entire products or components. Lean manufacturing has changed the nature of the assemblers' duties.
It has become more common to involve assemblers and fabricators in product development. Designers and engineers consult manufacturing workers during the design stage to improve product reliability and manufacturing efficiency. Some experienced assemblers work with designers and engineers to build prototypes or test products.
Although most assemblers and fabricators are classified as team assemblers, others specialize in producing one type of product or do the same or similar tasks throughout the assembly process.
The following are types of assemblers and fabricators:
Aircraft structure, surfaces, rigging, and systems assemblers fit, fasten, and install parts of airplanes, space vehicles, or missiles, such as wings, fuselage, landing gear, rigging and control equipment, or heating and ventilating systems.
Coil winders, tapers, and finishers wind wire coils of electrical components used in a variety of electric and electronic products, including resistors, transformers, generators, and electric motors.
Electrical and electronic equipment assemblers build products such as electric motors, computers, electronic control devices, and sensing equipment. Automated systems have been put in place because many small electronic parts are too small or fragile for human assembly. Much of the remaining work of electrical and electronic assemblers is done by hand during the small-scale production of electronic devices used in all types of aircraft, military systems, and medical equipment. Production by hand requires these workers to use devices such as soldering irons.
Electromechanical equipment assemblers assemble and modify electromechanical devices such as household appliances, computer tomography scanners, or vending machines. The workers use a variety of tools, such as rulers, rivet guns, and soldering irons.
Engine and machine assemblers construct, assemble, or rebuild engines, turbines, and machines used in automobiles, construction and mining equipment, and power generators.
Structural metal fabricators and fitters cut, align, and fit together structural metal parts and may help weld or rivet the parts together.
Fiberglass laminators and fabricators laminate layers of fiberglass on molds to form boat decks and hulls, bodies for golf carts, automobiles, or other products.
Team assemblers work on an assembly line, but they rotate through different tasks, rather than specializing in a single task. The team may decide how the work is assigned and how different tasks are done. Some aspects of lean production, such as rotating tasks and seeking worker input on improving the assembly process, are common to all assembly and fabrication occupations.
Timing device assemblers, adjusters, and calibrators do precision assembling or adjusting of timing devices within very narrow tolerances.
Electricians install and maintain electrical systems in homes, businesses, and factories.
Electricians typically do the following:
Almost every building has an electrical system that is installed during construction and maintained after that. Electricians do both the installing and maintaining of electrical systems.
Installing electrical systems is less complicated than maintaining older equipment. This is because it is easier to get to electrical wiring during construction. Maintaining older equipment, however, involves identifying problems and repairing malfunctioning equipment that is sometimes difficult to reach. Electricians doing maintenance work may need to fix or replace outlets, circuit breakers, motors, or robotic control systems.
Electricians read blueprints, which are technical diagrams of electrical systems that show the location of circuits, outlets, and other equipment. They use different types of hand and power tools, such as pipe benders, to run and protect wiring. Other commonly used hand and power tools include screwdrivers, wire strippers, drills, and saws. While troubleshooting, electricians also may use ammeters, voltmeters, and multimeters to find problems and ensure that components are working properly.
Many electricians work independently, but sometimes they collaborate with others. For example, experienced electricians may work with building engineers and architects to help design electrical systems in new construction. Some electricians also may consult with other construction specialists, such as elevator installers and heating and air conditioning workers, to help install or maintain electrical or power systems. At larger companies, electricians are more likely to work as part of a crew; they may direct helpers and apprentices to complete jobs.
The following are examples of occupational specialties:
Inside electricians maintain and repair large motors, equipment, and control systems in businesses and factories. They use their knowledge of electrical systems to help these facilities run safely and efficiently. Some also install the wiring for businesses and factories that are being built. To minimize equipment failure, inside electricians often perform scheduled maintenance.
Residential electricians install wiring and troubleshoot electrical problems in peoples' homes. Those who work in new-home construction install outlets and provide access to power where needed. Those who work in maintenance and remodeling repair and replace faulty equipment. For example, if a circuit breaker is tripped, electricians determine the reason and fix it.