Roofers repair and install the roofs of buildings using a variety of materials, including shingles, asphalt, and metal.
Roofers typically do the following:
Properly installed roofs keep water from leaking into buildings and damaging the interior, equipment, or furnishings.
There are two basic types of roofs, low-slope and steep-slope:
A small but increasing number of buildings now have “green” roofs that incorporate landscape roofing systems. A landscape roofing system typically begins with a single or multiple waterproof layers. After that layer is proven to be leak free, roofers put a root barrier over it, and, finally, layers of soil, in which vegetation is planted. Roofers must ensure that the roof is watertight and can endure the weight and water needs of the plants.
Construction equipment operators drive, maneuver, or control the heavy machinery used to construct roads, bridges, buildings, and other structures.
Construction equipment operators typically do the following:
Construction equipment operators use machinery to move construction materials, earth, and other heavy materials at construction sites and mines. They operate equipment that clears and grades land to prepare it for construction of roads, bridges, and buildings, as well as airport runways, power generation facilities, dams, levees, and other structures.
The following are types of construction equipment operators:
Operating engineers and other construction equipment operators work with one or several types of power construction equipment. They may operate excavation and loading machines equipped with scoops, shovels, or buckets that dig sand, gravel, earth, or similar materials. In addition to operating the familiar bulldozer, they operate trench excavators, road graders, and similar equipment. Sometimes, they may drive and control industrial trucks or tractors equipped with forklifts or booms for lifting materials. They also may operate and maintain air compressors, pumps, and other power equipment at construction sites.
Paving and surfacing equipment operators control the machines that spread and level asphalt or spread and smooth concrete for roadways or other structures. Paving and surfacing equipment operators may specialize further:
Piledriver operators use large machines mounted on skids, barges, or cranes to hammer piles into the ground. Piles are long, heavy beams of wood or steel driven into the ground to support retaining walls, bridges, piers, or building foundations. Some piledriver operators work on offshore oil rigs.
Some workers operate cranes to move construction materials. For more information on these workers, see the profile on material moving machine operators.
Occupational health and safety technicians collect data on the safety and health conditions of the workplace. Technicians work with occupational health and safety specialists in conducting tests and measuring hazards to help prevent harm to workers, property, the environment, and the general public. For more information, see the profile on occupational health and safety specialists.
Occupational health and safety technicians typically do the following:
Technicians conduct tests and collect samples and measurements as part of workplace inspections. For example, they may collect and handle samples of dust, mold, gases, vapors, or other potentially hazardous materials. They conduct both routine inspections and special inspections that a specialist orders. For more information about specialists, see the profile on occupational health and safety specialists.
Technicians may examine and test machinery and equipment such as scaffolding and lifting devices to be sure that they meet appropriate safety regulations. They may check that workers are using protective gear, such as masks and hardhats, as regulations say they must.
Technicians also check that hazardous materials are stored correctly. They test and identify work areas for potential health and safety hazards.
In addition to making workers safer, technicians work with specialists to increase worker productivity by reducing the number of worker absences and equipment downtime. They save companies money by lowering insurance premiums and worker compensation payments and by preventing government fines.
Technicians' duties vary based on where they are employed. For example, a technician may test the levels of biohazard at a waste processing plant or may inspect the lighting and ventilation in an office setting. Both of these inspections are focused on maintaining the health of the workers and the environment.
The responsibilities of occupational health and safety technicians vary by industry, workplace, and types of hazards affecting employees. The following are examples of types of occupational health and safety technicians:
Environmental protection technicians evaluate and coordinate the storage and handling of hazardous waste, the cleanup of contaminated soil or water, evaluation of air pollution, or other activities that affect the environment.
Health physics technicians work in places that use radiation and radioactive material. Their goal is to protect people and the environment from hazardous radiation exposure.
Industrial hygiene technicians examine the workplace for health hazards, such as exposure to lead, asbestos, pesticides, or contagious diseases.
Mine examiners inspect mines for proper air flow and health hazards such as the buildup of methane or other harmful gases.
Cost estimators collect and analyze data to estimate the time, money, resources, and labor required for product manufacturing, construction projects, or services. Some specialize in a particular industry or product type.
Cost estimators typically do the following:
Accurately predicting the cost, size, and duration of future construction and manufacturing projects is vital to the survival of any business. Cost estimators' calculations give managers or investors this information.
When making calculations, estimators analyze many inputs to determine how much time, money, and labor a project needs, or how profitable it will be. These estimates have to take many factors into account, including allowances for wasted material, bad weather, shipping delays, and other factors that can increase costs and lower profitability.
Cost estimators use sophisticated computer software, including database, simulation, and complex mathematical programs. Cost estimators often use a computer database with information on the costs of other similar projects.
General contractors usually hire cost estimators for specific parts of a large construction project, such as estimating the electrical work or the excavation phase. In such cases, the estimator calculates the cost of the construction phase for which the contractor is responsible, rather than calculating the cost of the entire project. The general contractor usually also has a cost estimator who calculates the total project cost by analyzing the bids that the subcontractors' cost estimators prepared.
Some estimators are hired by manufacturers to analyze certain products or processes.
The following are the two primary types of cost estimators:
Construction cost estimators estimate construction work. More than half of all cost estimators work in the construction industry. They may, for example, estimate the total cost of building a bridge or a highway. They may identify direct costs, such as raw materials and labor requirements, and set a timeline for the project. Although many work directly for construction firms, some work for contractors, architects, and engineering firms.
Manufacturing cost estimators calculate the costs of developing, producing, or redesigning a company's goods and services. For example, a cost estimator working for a home appliance manufacturer may determine whether a new type of dishwasher will be profitable to manufacture.
Some manufacturing cost estimators work in software development. Many high-technology products require a considerable amount of computer programming, and the costs of software development are difficult to calculate.
Two other groups also sometimes do cost estimating in their jobs. Operations research, production control, cost, and price analysts who work for government agencies may do significant amounts of cost estimating in the course of their usual duties. Construction managers also may spend considerable time estimating costs. For more information, see the profiles on operations research analysts and construction managers.
Construction and building inspectors ensure that new construction, changes, or repairs comply with local and national building codes and ordinances, zoning regulations, and contract specifications.
Construction and building inspectors typically do the following:
Construction and building inspectors examine buildings, highways and streets, sewer and water systems, dams, bridges, and other structures. They also inspect electrical; heating, ventilation, air-conditioning, and refrigeration (HVACR); and plumbing systems. Although no two inspections are alike, inspectors do an initial check during the first phase of construction and follow-up inspections throughout the construction project. When the project is finished, they do a final, comprehensive inspection.
The following are types of construction and building inspectors:
Building inspectors check the structural quality and general safety of buildings. Some specialize in structural steel or reinforced-concrete structures, for example.
Electrical inspectors examine the installed electrical systems to ensure they function properly and comply with electrical codes and standards. The inspectors visit worksites to inspect new and existing sound and security systems, wiring, lighting, motors, and generating equipment. They also inspect the installed electrical wiring for HVACR systems and appliances.
Elevator inspectors examine lifting and conveying devices, such as elevators, escalators, moving sidewalks, lifts and hoists, inclined railways, ski lifts, and amusement rides.
Home inspectors typically inspect newly built or previously owned homes, condominiums, townhomes, and other dwellings. Prospective home buyers often hire home inspectors to check and report on a home's structure and overall condition. Sometimes, homeowners hire a home inspector to evaluate their home's condition before placing it on the market.
In addition to examining structural quality, home inspectors examine all home systems and features, including roofing, exterior walls, attached garage or carport, foundation, interior, plumbing, electrical, and HVACR systems. They look for and report violations of building codes, but they do not have the power to enforce compliance with the codes.
Mechanical inspectors examine the installation of HVACR systems and equipment to ensure that they are installed and function properly. They also may inspect commercial kitchen equipment, gas-fired appliances, and boilers.
Plan examiners determine whether the plans for a building or other structure comply with building codes. They also determine whether the structure is suited to the engineering and environmental demands of the building site.
Plumbing inspectors examine the installation of potable water, waste, and vent piping systems to ensure the safety and health of the drinking water system, piping for industrial uses, and the sanitary disposal of waste.
Public works inspectors ensure that federal, state, and local government water and sewer systems, highways, streets, bridges, and dam construction conform to detailed contract specifications. Workers inspect excavation and fill operations, the placement of forms for concrete, concrete mixing and pouring, asphalt paving, and grading operations. Public works inspectors may specialize in highways, structural steel, reinforced concrete, or ditches. Others specialize in dredging operations required for bridges and dams or for harbors.
Specification inspectors ensure that work is performed according to design specifications. Specification inspectors represent the owner's interests, not those of the general public. Insurance companies and financial institutions also may use their services.
A primary concern of building inspectors is fire prevention safety. For more information, see the profile on fire inspectors and investigators.