Flood Control

Carpenters construct and repair building frameworks and structures--such as stairways, doorframes, partitions, and rafters--made from wood and other materials. They also may install kitchen cabinets, siding, and drywall.

Carpenters typically do the following:

• Follow blueprints and building plans to meet the needs of clients
• Install structures and fixtures, such as windows and molding
• Measure, cut, or shape wood, plastic, fiberglass, drywall, and other materials
• Construct building frameworks, including wall studs, floor joists, and doorframes
• Help put up, level, and install building framework with the aid of large pulleys and cranes
• Inspect and replace damaged framework or other structures and fixtures
• Instruct and direct laborers and other construction trade helpers

Carpenters are one of the most versatile construction occupations, with workers usually doing a variety of tasks. For example, some carpenters insulate office buildings; others install drywall or kitchen cabinets in homes. Those who help construct large buildings or bridges often make the wooden concrete forms for cement footings or pillars. Some carpenters build braces and scaffolding for buildings.

Carpenters use many different hand and power tools to cut and shape wood, plastic, fiberglass, or drywall. They commonly use handtools, including squares, levels, and chisels, as well as many power tools, such as sanders, circular saws, and nail guns. Carpenters put materials together with nails, screws, staples, and adhesives, and do a final check of their work to ensure accuracy. They use a tape measure on every project because proper measuring increases productivity, reduces waste, and ensures that the pieces being cut are the proper size.

The following are types of carpenters:

Residential carpenters typically specialize in new-home, townhome, and condominium building and remodeling. As part of a single job, they might build and set forms for footings, walls and slabs, and frame and finish exterior walls, roofs, and decks. They frame interior walls, build stairs, and install drywall, crown molding, doors, and kitchen cabinets. Highly-skilled carpenters may also tile floors and lay wood floors and carpet. Fully-trained construction carpenters are easily able to switch from new-home building to remodeling.

Commercial carpenters typically remodel and help build commercial office buildings, hospitals, hotels, schools, and shopping malls. Some specialize in working with light gauge and load-bearing steel framing for interior partitions, exterior framing, and curtain wall construction. Others specialize in working with concrete forming systems and finishing interior and exterior walls, partitions, and ceilings. Highly skilled carpenters can usually do many of the same tasks as residential carpenters.

Industrial carpenters typically work in civil and industrial settings where they put up scaffolding and build and set forms for pouring concrete. Some industrial carpenters build tunnel bracing or partitions in underground passageways and mines to control the circulation of air to worksites. Others build concrete forms for tunnels, bridges, dams, power plants, or sewer construction projects.

Construction managers plan, coordinate, budget, and supervise construction projects from early development to completion.

Construction managers typically do the following:

• Prepare and negotiate cost estimates, budgets, and work timetables
• Select appropriate construction methods and strategies
• Interpret and explain contracts and technical information to workers and other professionals
• Report on work progress and budget matters to clients
• Collaborate with architects, engineers, and other construction and building specialists
• Instruct and supervise construction personnel and activities onsite
• Respond to work delays and other problems and emergencies
• Select, hire, and instruct laborers and subcontractors  
• Comply with legal requirements, building and safety codes, and other regulations

Construction managers, often called general contractors or project managers, coordinate and supervise a wide variety of projects, including the building of all types of residential, commercial, and industrial structures, roads, bridges, powerplants, schools, and hospitals. They oversee specialized contractors and other personnel. Construction managers schedule and coordinate all design and construction processes to ensure a productive and safe work environment. They also make sure jobs are completed on time and on budget with the right amount of tools, equipment, and materials. Many managers also are responsible for obtaining necessary permits and licenses. They are often responsible for multiple projects at a time.

Construction managers work closely with other building specialists, such as architects, engineers, and a variety of trade workers, such as stonemasons, electricians, and carpenters. Projects may require specialists in everything from structural metalworking and painting, to landscaping, building roads, installing carpets, and excavating sites. Depending on the project, construction managers also may interact with lawyers and local government officials. For example, when working on city-owned property or municipal buildings, managers sometimes confer with city council members to ensure that all regulations are met.

For projects too large to be managed by one person, such as office buildings and industrial complexes, a construction manager would only be in charge of one part of the project. Each construction manager would oversee a specific construction phase and choose subcontractors to complete it. Construction managers may need to collaborate and coordinate with other construction managers who are responsible for different aspects of the project.

To maximize efficiency and productivity, construction managers often use specialized cost-estimating and planning software to effectively budget the time and money required to complete specific projects. Many managers also use software to determine the best way to get materials to the building site. For more information, see the profile on cost estimators.

Environmental engineering technicians engineering technicians carry out the plans that environmental engineers develop.

Environmental engineering technicians typically do the following:

• Set up, test, operate, and modify equipment for preventing or cleaning up environmental pollution
• Maintain project records and computer program files
• Conduct pollution surveys, collecting and analyzing samples such as air and ground water
• Perform indoor and outdoor environmental quality work
• Work to mitigate sources of environmental pollution
• Review technical documents to ensure completeness and conformance to requirements
• Review work plans to schedule activities
• Arrange for the disposal of lead, asbestos, and other hazardous materials

In laboratories, environmental engineering technicians record observations, test results, and document photographs. To keep the laboratory supplied, they also may get product information, identify vendors and suppliers, and order materials and equipment.

Environmental engineering technicians also help environmental engineers develop devices for cleaning up environmental pollution. They also inspect facilities for compliance with the regulations that govern substances such as asbestos, lead, and wastewater.

Environmental scientists and specialists use their knowledge of the natural sciences to protect the environment. They identify problems and find solutions that minimize hazards to the health of the environment and the population.

Environmental scientists and specialists typically do the following:

• Determine data collection methods for research projects, investigations, and surveys
• Collect environmental data, such as samples of air, soil, water, food, and other materials, for scientific analysis
• Analyze samples, surveys, and other information to identify and assess threats to the environment
• Develop plans to prevent, control, or fix environmental problems, such as pollution and harm to land or water
• Develop plans to restore polluted or contaminated land or water
• Provide information and guidance to government officials, businesses, and the general public on possible environmental hazards and health risks
• Prepare technical reports and presentations that explain their research and findings

Environmental scientists and specialists analyze environmental problems and develop solutions. For example, many environmental scientists and specialists work to reclaim lands and waters that have been contaminated by pollution. Others assess the risks new construction projects pose to the environment and make recommendations to governments and businesses on how to minimize the environmental impact of these projects. They also identify ways that human behavior can be changed to avoid problems such as the depletion of the ozone layer.

The federal government and many state and local governments have regulations to ensure that there is clean air to breathe, safe water to drink, and no hazardous materials in the soil. The regulations also place limits on development, particularly near sensitive parts of the ecosystem, such as wetlands. Many environmental scientists and specialists work for the government to ensure that these regulations are followed. Other environmental scientists work for consulting firms that help companies comply with regulations and policies.

Some environmental scientists and specialists focus on environmental regulations that are designed to protect people's health, while others focus on regulations designed to minimize society's impact on the ecosystem. The following are examples of types of specialists:

Environmental health specialists study how environmental factors impact human health. They investigate potential health risks, such as unsafe drinking water, disease, and food safety. They also educate the public about potential health risks present in the environment.

Environmental protection specialists monitor the effect human activity has on the environment. They investigate sources of pollution and develop prevention, control, and remediation plans.

Other environmental scientists do work and receive training that is similar to that of other physical or life scientists, but they focus on environmental issues. Environmental chemists are an example.

Environmental chemists study the effects that various chemicals have on ecosystems. For example, they look at how acids affect plants, animals, and people. Some areas in which they work include waste management and the remediation of contaminated soils, water, and air.

Many people with backgrounds in environmental science become professors and teachers. For more information, see the profile on postsecondary teachers.

Plumbers, pipefitters, and steamfitters install and repair pipes that carry water, steam, air, or other liquids or gases to and in businesses, homes, and factories.

Plumbers, pipefitters, and steamfitters typically do the following:

• Install pipes and fixtures
• Study blueprints and follow state and local building codes
• Determine the amount of material and type of equipment needed
• Inspect and test installed pipe systems and pipelines
• Troubleshoot and repair systems that are not working
• Replace worn parts

Although plumbers, pipefitters, and steamfitters are three distinct specialties, their duties are often similar. For example, they all install pipes and fittings that carry water, steam, air, or other liquids or gases. They connect pipes, determine the necessary materials for a job, and perform pressure tests to ensure a pipe system is airtight and watertight.

Plumbers, pipefitters, and steamfitters install, maintain, and repair many different types of pipe systems. Some of these systems carry water, dispose of waste, supply gas to ovens, or heat and cool buildings. Other systems, such as those in power plants, carry the steam that powers huge turbines. Pipes also are used in manufacturing plants to move acids, gases, and waste byproducts through the production process.

Master plumbers on construction jobs may be involved with developing blueprints that show where all the pipes and fixtures will go. Their input helps ensure that a structure's plumbing meets building codes, stays within budget, and works well with the location of other features, such as electric wires.

Plumbers and fitters may use many different materials and construction techniques, depending on the type of project. Residential water systems, for example, use copper, steel, and plastic pipe that one or two plumbers can install. Power-plant water systems, by contrast, are made of large steel pipes that usually take a crew of pipefitters to install. Some workers install stainless steel pipes on dairy farms and in factories, mainly to prevent contamination.

Plumbers and fitters sometimes cut holes in walls, ceilings, and floors. With some pipe systems, workers may hang steel supports from ceiling joists to hold the pipe in place. Because pipes are seldom manufactured to the exact size or length, plumbers and fitters measure and then cut and bend lengths of pipe as needed. Their tools include saws, pipe cutters, and pipe-bending machines.

They then connect the pipes, using methods that vary by type of pipe. For example, copper pipe is joined with solder, but steel pipe is often screwed together.

In addition to installation and repair work, journey- and master-level plumbers, pipefitters, and steamfitters often direct apprentices and helpers.

Following are examples of occupational specialties:

Plumbers install and repair water, drainage, and gas pipes in homes, businesses, and factories. They install and repair large water lines, such as those that supply water to buildings, and smaller ones, including ones that supply water to refrigerators. Plumbers also install plumbing fixtures--bathtubs, showers, sinks, and toilets--and appliances such as dishwashers, garbage disposals, and water heaters. They also fix plumbing problems. For example, when a pipe is clogged or leaking, plumbers remove the clog or replace the pipe. Some plumbers maintain septic systems, the large, underground holding tanks that collect waste from houses not connected to a city or county's sewer system.

Pipefitters install and maintain pipes that carry chemicals, acids, and gases. These pipes are mostly in manufacturing, commercial, and industrial settings. They often install and repair pipe systems in power plants, as well as heating and cooling systems in large office buildings. Some pipefitters specialize:

• Gasfitters install pipes that provide clean oxygen to patients in hospitals.
• Sprinklerfitters install and repair fire sprinkler systems in businesses, factories, and residential buildings.
• Steamfitters installpipe systems that move steam under high pressure. Most steamfitters work at campus and natural gas power plants where heat and electricity is generated, but others work in factories that use high-temperature steam pipes.

Drywall and ceiling tile installers hang wallboards to walls and ceilings inside buildings. Tapers prepare the wallboards for painting, using tape and other materials. Many workers do both installing and taping.

Drywall installers typically do the following:

• Review design plans to minimize the number of cuts and waste of wallboard
• Measure the location of electrical outlets, plumbing, windows, and vents
• Cut drywall to the right size, using utility knives and power saws
• Fasten drywall panels to interior wall studs, using nails or screws
• Trim and smooth rough edges so boards join evenly

Ceiling tile installers typically do the following:

• Measure according to blueprints or drawings
• Nail or screw supports
• Put tiles or sheets of shock-absorbing materials on ceilings  
• Keep the tile in place with cement adhesive, nails, or screws

Tapers typically do the following:

• Prepare wall surface (wallboard) by patching nail holes
• Apply tape and use sealing compound to cover joints between wallboards
• Apply additional coats of sealing compound to create an even surface
• Sand all joints and holes to a smooth, seamless finish

Installers are also called framers or hangers. Tapers are also called finishers. Ceiling tile installers are sometimes called acoustical carpenters because they work with tiles that block sound.

Once wallboards are hung, workers use increasingly wider trowels to spread multiple coats of spackle over cracks, indentations, and any remaining imperfections. Some workers may use a mechanical applicator, a tool that spreads sealing compound on the wall joint while dispensing and setting tape at the same time.

To work on ceilings, drywall and ceiling tile installers and tapers may use mechanical lifts or stand on stilts, ladders, or scaffolds.

Janitors and building cleaners keep many types of buildings clean, orderly, and in good condition.

Janitors and building cleaners typically do the following:

• Gather and empty trash and trash bins
• Clean building floors by sweeping, mopping, or vacuuming them
• Clean bathrooms and stock them with soap, toilet paper, and other supplies
• Keep buildings secure by locking doors
• Clean spills and other hazards using sponges and squeegees
• Wash windows, walls, and glass
• Order cleaning supplies
• Make minor repairs to the building, such as changing light bulbs
• Notify managers when the building needs major repairs

Janitors and building cleaning workers keep office buildings, schools, hospitals, retail stores, hotels, and other places clean, sanitary, and in good condition. Some do only cleaning, while others have a wide range of duties.

In addition to keeping the inside of buildings clean and orderly, some janitors and building cleaners work outdoors, mowing lawns, sweeping walkways, or shoveling snow. Some janitors also monitor the heating and cooling system, ensuring that it functions properly.

Janitors and building cleaners use many tools and equipment. Simple cleaning tools may include mops, brooms, rakes, and shovels. Other tools may include snowblowers and floor buffers.

Some janitors may be responsible for repairing small problems with electricity or plumbing, such as leaky faucets.

Painters apply paint, stain, and coatings to walls, buildings, bridges, and other structures.

Painters typically do the following:

• Cover floors and furniture with drop-cloths and tarps to protect surfaces
• Remove fixtures such as pictures, door knobs, or electric switch covers
• Put up scaffolding and set up ladders
• Fill holes and cracks with caulk, putty, plaster, or other compounds
• Prepare surfaces by scraping, wire brushing, or sanding to a smooth finish
• Calculate the area to be painted and the amount of paint needed
• Apply primers or sealers so the paint will adhere
• Choose and mix paints and stains to reach desired color and appearance
• Apply paint or other finishes using hand brushes, rollers, or sprayers

Applying paint to interior walls makes surfaces attractive and vibrant. In addition, paints and other sealers protect exterior surfaces from erosion caused by exposure to the weather.

Because there are several ways to apply paint, workers must be able to choose the proper tool for each job, such as the correct roller, power sprayer, and the right size brush. Choosing the right tool typically depends on the surface to be covered and the characteristics of the finish.

A few painters--mainly industrial--must use special safety equipment. For example, painting in confined spaces such as the inside of a large storage tank, requires workers to wear self-contained suits to avoid inhaling toxic fumes. When painting bridges, tall buildings, or oil rigs, painters may work from scaffolding, bosun's chairs, and harnesses to reach work areas.

The following are examples of types of painters:  

Construction painters apply paints, stains, and coatings to interior and exterior walls, new buildings, and other structural surfaces.

Maintenance painters remove old finishes and apply paints, stains, and coatings later in a structure's life. Some painters specialize in painting or coating industrial structures, such as bridges and oil rigs, to prevent corrosion.

Artisan painters specialize in creating distinct finishes by using one of many decorative techniques. One technique is adding glaze for added depth and texture. Other common techniques may include sponging, distressing, rag-rolling, color blocking, and faux finishes. 

Painting and coating workers apply materials to manufactured products, such as furniture, toys and pottery, as well as transportation equipment including trucks, buses, boats, and airplanes. For more information about these painters, see the profile on painting and coating workers.

Environmental engineering technicians engineering technicians carry out the plans that environmental engineers develop.

Environmental engineering technicians typically do the following:

• Set up, test, operate, and modify equipment for preventing or cleaning up environmental pollution
• Maintain project records and computer program files
• Conduct pollution surveys, collecting and analyzing samples such as air and ground water
• Perform indoor and outdoor environmental quality work
• Work to mitigate sources of environmental pollution
• Review technical documents to ensure completeness and conformance to requirements
• Review work plans to schedule activities
• Arrange for the disposal of lead, asbestos, and other hazardous materials

In laboratories, environmental engineering technicians record observations, test results, and document photographs. To keep the laboratory supplied, they also may get product information, identify vendors and suppliers, and order materials and equipment.

Environmental engineering technicians also help environmental engineers develop devices for cleaning up environmental pollution. They also inspect facilities for compliance with the regulations that govern substances such as asbestos, lead, and wastewater.

Hazardous materials (hazmat) removal workers identify and dispose of asbestos, radioactive and nuclear waste, arsenic, lead, and other hazardous materials. They also clean up materials that are flammable, corrosive, reactive, or toxic.

Hazmat removal workers typically do the following:

• Comply with safety procedures and federal laws regarding waste disposal
• Construct scaffolding or build containment areas before cleaning up
• Remove or clean up hazardous materials that are found or spilled
• Clean contaminated equipment for reuse
• Operate equipment that removes and stores waste materials
• Keep records of cleanup activities

Hazmat removal workers clean up materials that are harmful to people and the environment. The work they do depends on the substances they are cleaning. Removing lead and asbestos is different from cleaning up radiation contamination and toxic spills. Differences also can relate to why these workers have been called in to clean a site. For example, cleaning up a fuel spill from a train derailment is more urgent than removing lead paint from a bridge.

The following are types of hazmat removal workers:

Asbestos abatement workers and lead abatement workers remove asbestos and lead from buildings that are going to be fixed up or taken down. Most of this work is in older buildings that were originally built with asbestos insulation and lead-based paints--both of which are now banned from being used in newer buildings and must be removed from older ones.

Until the 1970s, asbestos was often used in buildings for fireproofing, insulation, and other uses. However, asbestos particles can cause deadly lung diseases. Similarly, until the 1970s, lead was commonly used in paint, pipes, and plumbing fixtures. Inhaling lead dust or ingesting chips of lead-based paint can cause serious health problems, though, especially in children.

Lead abatement workers use chemicals and may need to know how to operate sandblasters, high-pressure water sprayers, and other common tools.

Decommissioning and decontamination workers remove and treat radioactive materials generated by nuclear facilities and powerplants. They break down contaminated items such as “gloveboxes,” which are used to process radioactive materials. When a facility is being closed or decommissioned (taken out of service), these workers clean the facility and decontaminate it from radioactive materials.

Decontamination technicians do tasks similar to those of janitors and cleaners, but the items and areas they clean are radioactive. Some of these jobs are now being done by robots controlled by people away from the contamination site. Increasingly, many of these remote devices automatically monitor and survey floors and walls for contamination.

Emergency and disaster response workers must work quickly to clean up hazardous materials after train and trucking accidents. Immediate, thorough cleanups help to control and prevent more damage to accident or disaster sites.

Radiation-protection technicians use radiation survey meters and other remote devices to locate and assess the hazard associated with radiated materials, operate high-pressure cleaning equipment for decontamination, and package radioactive materials for moving or disposing.

Treatment, storage, and disposal workers transport and prepare materials for treatment, storage, or disposal. To ensure proper treatment of materials, workers must follow laws enforced by the U.S. Environmental Protection Agency (EPA) or the U.S. Occupational Safety and Health Administration (OSHA). At incinerator facilities, treatment, storage, and disposal workers move materials from the customer or service center to the incinerator. At landfills, they organize and track the location of items in the landfill and may help change the state of a material from liquid to solid to prepare it to be stored. These workers typically operate heavy machinery, such as forklifts, earthmoving machinery, and large trucks and rigs.

Mold remediation makes up a small segment of hazardous materials removal work. Although mold is present in almost all structures and is not usually defined as a hazardous material, some mold--especially the types that cause allergic reactions--can infest a building to such a degree that extensive efforts must be taken to remove it safely.

Environmental engineers use the principles of engineering, soil science, biology, and chemistry to develop solutions to environmental problems. They are involved in efforts to improve recycling, waste disposal, public health, and control of water and air pollution. They also address global issues, such as safe drinking water, climate change, and sustainability.

Environmental engineers typically do the following:

• Prepare, review, and update environmental investigation reports
• Design projects leading to environmental protection, such as water reclamation facilities, air pollution control systems, and operations that convert waste to energy
• Obtain, update, and maintain plans, permits, and standard operating procedures
• Provide technical support for environmental remediation projects and legal actions
• Analyze scientific data and do quality-control checks
• Monitor progress of environmental improvement programs
• Inspect industrial and municipal facilities and programs to ensure compliance with environmental regulations
• Advise corporations and government agencies about procedures for cleaning up contaminated sites

Environmental engineers conduct hazardous-waste management studies in which they evaluate the significance of the hazard and advise on treating and containing it. They also design municipal water supply and industrial wastewater treatment systems and research the environmental impact of proposed construction projects. Environmental engineers in government develop regulations to prevent mishaps.

Some environmental engineers study ways to minimize the effects of acid rain, global warming, automobile emissions, and ozone depletion. They also collaborate with environmental scientists, planners, hazardous waste technicians, engineers, and other specialists, such as experts in law and business, to address environmental problems and sustainability. For more information, see the job profiles on environmental scientists and specialists, hazardous materials removal workers, lawyers, and urban and regional planners.

Hydrologists study water and the water cycle. They study the movement, distribution, and other properties of water, and they analyze how these influence the surrounding environment. They use their expertise to solve problems concerning water quality and availability, for example.

Hydrologists typically do the following:

• Measure the properties of bodies of water, such as volume and stream flow
• Collect water and soil samples to test for certain properties, such as levels of pollution
• Apply research findings to help minimize the environmental impacts of pollution, erosion, and other problems
• Research ways to improve water conservation and preservation
• Use computer models to forecast future water supplies, the spread of pollution, and other events
• Evaluate the feasibility of water-related projects, such as hydroelectric power plants, irrigation systems, and waste treatment facilities
• Prepare written reports and presentations of their findings

Hydrologists use remote sensing equipment to collect data. They or technicians whom they supervise usually install and maintain this equipment.

They also use sophisticated computer programs to analyze and model data. They use sophisticated laboratory equipment to analyze chemical samples collected in the field.

Hydrologists work closely with engineers, scientists, and public officials to study and manage the water supply. For example, they work with policy makers to develop water conservation plans and with biologists to monitor marine wildlife.

Most hydrologists specialize in a specific water source or a certain aspect of the water cycle, such as the evaporation of water from lakes and streams. Some of the most common specialties are:

Groundwater hydrologists study the water below the Earth's surface. They decide the best locations for wells and the amount of water that should be pumped. They are often consulted about the best places to build waste disposal sites to ensure that the waste does not contaminate the groundwater.

Hydrometeorologists study the relationship between surface waters and water in the atmosphere. For example, to predict and prepare for droughts, they study how much rain or snow a particular area gets and how that evaporates.

Surface water hydrologists study water from above ground sources such as streams, lakes, and snow packs. They may predict future water levels and usage to help reservoir managers decide when to release or store water. They also produce flood forecasts and help develop flood management plans.

Some people with a hydrology background become professors or teachers. For more information, see the profile on postsecondary teachers.

Plumbers, pipefitters, and steamfitters install and repair pipes that carry water, steam, air, or other liquids or gases to and in businesses, homes, and factories.

Plumbers, pipefitters, and steamfitters typically do the following:

• Install pipes and fixtures
• Study blueprints and follow state and local building codes
• Determine the amount of material and type of equipment needed
• Inspect and test installed pipe systems and pipelines
• Troubleshoot and repair systems that are not working
• Replace worn parts

Although plumbers, pipefitters, and steamfitters are three distinct specialties, their duties are often similar. For example, they all install pipes and fittings that carry water, steam, air, or other liquids or gases. They connect pipes, determine the necessary materials for a job, and perform pressure tests to ensure a pipe system is airtight and watertight.

Plumbers, pipefitters, and steamfitters install, maintain, and repair many different types of pipe systems. Some of these systems carry water, dispose of waste, supply gas to ovens, or heat and cool buildings. Other systems, such as those in power plants, carry the steam that powers huge turbines. Pipes also are used in manufacturing plants to move acids, gases, and waste byproducts through the production process.

Master plumbers on construction jobs may be involved with developing blueprints that show where all the pipes and fixtures will go. Their input helps ensure that a structure's plumbing meets building codes, stays within budget, and works well with the location of other features, such as electric wires.

Plumbers and fitters may use many different materials and construction techniques, depending on the type of project. Residential water systems, for example, use copper, steel, and plastic pipe that one or two plumbers can install. Power-plant water systems, by contrast, are made of large steel pipes that usually take a crew of pipefitters to install. Some workers install stainless steel pipes on dairy farms and in factories, mainly to prevent contamination.

Plumbers and fitters sometimes cut holes in walls, ceilings, and floors. With some pipe systems, workers may hang steel supports from ceiling joists to hold the pipe in place. Because pipes are seldom manufactured to the exact size or length, plumbers and fitters measure and then cut and bend lengths of pipe as needed. Their tools include saws, pipe cutters, and pipe-bending machines.

They then connect the pipes, using methods that vary by type of pipe. For example, copper pipe is joined with solder, but steel pipe is often screwed together.

In addition to installation and repair work, journey- and master-level plumbers, pipefitters, and steamfitters often direct apprentices and helpers.

Following are examples of occupational specialties:

Plumbers install and repair water, drainage, and gas pipes in homes, businesses, and factories. They install and repair large water lines, such as those that supply water to buildings, and smaller ones, including ones that supply water to refrigerators. Plumbers also install plumbing fixtures--bathtubs, showers, sinks, and toilets--and appliances such as dishwashers, garbage disposals, and water heaters. They also fix plumbing problems. For example, when a pipe is clogged or leaking, plumbers remove the clog or replace the pipe. Some plumbers maintain septic systems, the large, underground holding tanks that collect waste from houses not connected to a city or county's sewer system.

Pipefitters install and maintain pipes that carry chemicals, acids, and gases. These pipes are mostly in manufacturing, commercial, and industrial settings. They often install and repair pipe systems in power plants, as well as heating and cooling systems in large office buildings. Some pipefitters specialize:

• Gasfitters install pipes that provide clean oxygen to patients in hospitals.
• Sprinklerfitters install and repair fire sprinkler systems in businesses, factories, and residential buildings.
• Steamfitters installpipe systems that move steam under high pressure. Most steamfitters work at campus and natural gas power plants where heat and electricity is generated, but others work in factories that use high-temperature steam pipes.

Roofers repair and install the roofs of buildings using a variety of materials, including shingles, asphalt, and metal.

Roofers typically do the following:

• Inspect problem roofs to determine the best way to repair them
• Measure roof to calculate the quantities of materials needed
• Replace damaged or rotting joists or plywood
• Install vapor barriers or layers of insulation
• Install shingles, asphalt, metal, or other materials to make the roof watertight
• Align roofing materials with edges of the roof
• Cut roofing materials to fit angles formed by walls, vents, or intersecting roof surfaces
• Cover exposed nail or screw heads with roofing cement or caulk to prevent leakage

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:

• Low-slope: About two-thirds of all roofs are low-slope. Most commercial, industrial, and apartment buildings have low-slope roofs. Low-slope roofs rise 4 inches or less per horizontal foot and are installed in layers.
  
  For low-slope roofs, roofers typically use several layers of roofing materials or felt membranes stuck together with hot bitumen (a tar-like substance). They glaze the top layer to make a smooth surface or embed gravel in the hot bitumen to make a rough surface.
  
  An increasing number of low-slope roofs are covered with a single-ply membrane of waterproof rubber or thermoplastic compounds.

• Steep-slope: Most of the remaining roofs are steep-slope. Most single-family houses have steep-slope roofs. Steep-slope roofs rise more than 4 inches per horizontal foot.
  
  For steep-slope roofs, roofers typically use asphalt shingles, which often cost less than other coverings. On steep-slope roofs, some roofers also install tile, solar shingles, fiberglass shingles, metal shingles, or shakes (rough wooden shingles).
  
  To apply shingles, roofers first lay, cut, and tack 3-foot strips of roofing over the entire roof. Then, starting from the bottom edge, they nail overlapping rows of shingles to the roof.

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.

Hydrologists study water and the water cycle. They study the movement, distribution, and other properties of water, and they analyze how these influence the surrounding environment. They use their expertise to solve problems concerning water quality and availability, for example.

Hydrologists typically do the following:

• Measure the properties of bodies of water, such as volume and stream flow
• Collect water and soil samples to test for certain properties, such as levels of pollution
• Apply research findings to help minimize the environmental impacts of pollution, erosion, and other problems
• Research ways to improve water conservation and preservation
• Use computer models to forecast future water supplies, the spread of pollution, and other events
• Evaluate the feasibility of water-related projects, such as hydroelectric power plants, irrigation systems, and waste treatment facilities
• Prepare written reports and presentations of their findings

Hydrologists use remote sensing equipment to collect data. They or technicians whom they supervise usually install and maintain this equipment.

They also use sophisticated computer programs to analyze and model data. They use sophisticated laboratory equipment to analyze chemical samples collected in the field.

Hydrologists work closely with engineers, scientists, and public officials to study and manage the water supply. For example, they work with policy makers to develop water conservation plans and with biologists to monitor marine wildlife.

Most hydrologists specialize in a specific water source or a certain aspect of the water cycle, such as the evaporation of water from lakes and streams. Some of the most common specialties are:

Groundwater hydrologists study the water below the Earth's surface. They decide the best locations for wells and the amount of water that should be pumped. They are often consulted about the best places to build waste disposal sites to ensure that the waste does not contaminate the groundwater.

Hydrometeorologists study the relationship between surface waters and water in the atmosphere. For example, to predict and prepare for droughts, they study how much rain or snow a particular area gets and how that evaporates.

Surface water hydrologists study water from above ground sources such as streams, lakes, and snow packs. They may predict future water levels and usage to help reservoir managers decide when to release or store water. They also produce flood forecasts and help develop flood management plans.

Some people with a hydrology background become professors or teachers. For more information, see the profile on postsecondary teachers.

Hazardous materials (hazmat) removal workers identify and dispose of asbestos, radioactive and nuclear waste, arsenic, lead, and other hazardous materials. They also clean up materials that are flammable, corrosive, reactive, or toxic.

Hazmat removal workers typically do the following:

• Comply with safety procedures and federal laws regarding waste disposal
• Construct scaffolding or build containment areas before cleaning up
• Remove or clean up hazardous materials that are found or spilled
• Clean contaminated equipment for reuse
• Operate equipment that removes and stores waste materials
• Keep records of cleanup activities

Hazmat removal workers clean up materials that are harmful to people and the environment. The work they do depends on the substances they are cleaning. Removing lead and asbestos is different from cleaning up radiation contamination and toxic spills. Differences also can relate to why these workers have been called in to clean a site. For example, cleaning up a fuel spill from a train derailment is more urgent than removing lead paint from a bridge.

The following are types of hazmat removal workers:

Asbestos abatement workers and lead abatement workers remove asbestos and lead from buildings that are going to be fixed up or taken down. Most of this work is in older buildings that were originally built with asbestos insulation and lead-based paints--both of which are now banned from being used in newer buildings and must be removed from older ones.

Until the 1970s, asbestos was often used in buildings for fireproofing, insulation, and other uses. However, asbestos particles can cause deadly lung diseases. Similarly, until the 1970s, lead was commonly used in paint, pipes, and plumbing fixtures. Inhaling lead dust or ingesting chips of lead-based paint can cause serious health problems, though, especially in children.

Lead abatement workers use chemicals and may need to know how to operate sandblasters, high-pressure water sprayers, and other common tools.

Decommissioning and decontamination workers remove and treat radioactive materials generated by nuclear facilities and powerplants. They break down contaminated items such as “gloveboxes,” which are used to process radioactive materials. When a facility is being closed or decommissioned (taken out of service), these workers clean the facility and decontaminate it from radioactive materials.

Decontamination technicians do tasks similar to those of janitors and cleaners, but the items and areas they clean are radioactive. Some of these jobs are now being done by robots controlled by people away from the contamination site. Increasingly, many of these remote devices automatically monitor and survey floors and walls for contamination.

Emergency and disaster response workers must work quickly to clean up hazardous materials after train and trucking accidents. Immediate, thorough cleanups help to control and prevent more damage to accident or disaster sites.

Radiation-protection technicians use radiation survey meters and other remote devices to locate and assess the hazard associated with radiated materials, operate high-pressure cleaning equipment for decontamination, and package radioactive materials for moving or disposing.

Treatment, storage, and disposal workers transport and prepare materials for treatment, storage, or disposal. To ensure proper treatment of materials, workers must follow laws enforced by the U.S. Environmental Protection Agency (EPA) or the U.S. Occupational Safety and Health Administration (OSHA). At incinerator facilities, treatment, storage, and disposal workers move materials from the customer or service center to the incinerator. At landfills, they organize and track the location of items in the landfill and may help change the state of a material from liquid to solid to prepare it to be stored. These workers typically operate heavy machinery, such as forklifts, earthmoving machinery, and large trucks and rigs.

Mold remediation makes up a small segment of hazardous materials removal work. Although mold is present in almost all structures and is not usually defined as a hazardous material, some mold--especially the types that cause allergic reactions--can infest a building to such a degree that extensive efforts must be taken to remove it safely.

Boilermakers assemble, install, and repair boilers, closed vats, and other large vessels or containers that hold liquids and gases.

Boilermakers typically do the following:

• Use blueprints to determine locations, positions, or dimensions of parts
• Install small premade boilers into buildings and manufacturing facilities
• Lay out prefabricated parts of larger boilers before assembling them
• Assemble boiler tanks, often using robotic or automatic welders
• Test and inspect boiler systems for leaks or defects
• Clean vats using scrapers, wire brushes, and cleaning solvents
• Replace or repair broken valves, pipes, or joints, using hand and power tools, gas torches, and welding equipment

Boilers, tanks, and vats are used in many buildings, factories, and ships. Boilers heat water or other fluids under extreme pressure to generate electric power and to provide heat. Large tanks and vats are used to store and process chemicals, oil, beer, and hundreds of other products.

Boilers are made out of steel, iron, copper, or stainless steel. Manufacturers are increasingly automating the production of boilers to improve the quality of these vessels. However, boilermakers still use many tools in making or repairing boilers. For example, they use hand and power tools or flame cutting torches to cut pieces for a boiler. To bend the pieces into shape and accurately line them up, boilermakers use plumb bobs, levels, wedges, and turnbuckles.

If the plate sections are very large, large cranes lift the parts into place. Once they have the parts lined up, they use metalworking machinery and other tools to remove irregular edges so the parts fit together properly. They join the parts by bolting, welding, or riveting them together.

In addition to installing and maintaining boilers and other vessels, boilermakers help erect and repair air pollution equipment, blast furnaces, water treatment plants, storage and process tanks, and smokestacks. Boilermakers also install refractory brick and other heat-resistant materials in fireboxes or pressure vessels. Some install and maintain the huge pipes used in dams to send water to and from hydroelectric power generation turbines.

Because boilers last a long time--sometimes 50 years or more--boilermakers must regularly maintain them and upgrade parts. They frequently inspect fittings, feed pumps, safety and check valves, water and pressure gauges, and boiler controls.

Construction managers plan, coordinate, budget, and supervise construction projects from early development to completion.

Construction managers typically do the following:

• Prepare and negotiate cost estimates, budgets, and work timetables
• Select appropriate construction methods and strategies
• Interpret and explain contracts and technical information to workers and other professionals
• Report on work progress and budget matters to clients
• Collaborate with architects, engineers, and other construction and building specialists
• Instruct and supervise construction personnel and activities onsite
• Respond to work delays and other problems and emergencies
• Select, hire, and instruct laborers and subcontractors  
• Comply with legal requirements, building and safety codes, and other regulations

Construction managers, often called general contractors or project managers, coordinate and supervise a wide variety of projects, including the building of all types of residential, commercial, and industrial structures, roads, bridges, powerplants, schools, and hospitals. They oversee specialized contractors and other personnel. Construction managers schedule and coordinate all design and construction processes to ensure a productive and safe work environment. They also make sure jobs are completed on time and on budget with the right amount of tools, equipment, and materials. Many managers also are responsible for obtaining necessary permits and licenses. They are often responsible for multiple projects at a time.

Construction managers work closely with other building specialists, such as architects, engineers, and a variety of trade workers, such as stonemasons, electricians, and carpenters. Projects may require specialists in everything from structural metalworking and painting, to landscaping, building roads, installing carpets, and excavating sites. Depending on the project, construction managers also may interact with lawyers and local government officials. For example, when working on city-owned property or municipal buildings, managers sometimes confer with city council members to ensure that all regulations are met.

For projects too large to be managed by one person, such as office buildings and industrial complexes, a construction manager would only be in charge of one part of the project. Each construction manager would oversee a specific construction phase and choose subcontractors to complete it. Construction managers may need to collaborate and coordinate with other construction managers who are responsible for different aspects of the project.

To maximize efficiency and productivity, construction managers often use specialized cost-estimating and planning software to effectively budget the time and money required to complete specific projects. Many managers also use software to determine the best way to get materials to the building site. For more information, see the profile on cost estimators.

Laundry and dry-cleaning workers clean clothing, linens, drapes, and other articles, using washing, drying, and dry-cleaning machines. They also may clean leather, suede, furs, and rugs.

Laundry and dry-cleaning workers typically do the following:

• Receive items from customers and mark them with codes or names
• Inspect articles for stains and fabrics that require special care
• Sort articles to be cleaned by fabric type, color, and cleaning technique
• Load clothing into laundry and dry-cleaning machines
• Add detergent, bleach, and other chemicals to laundry and dry-cleaning machines
• Remove, sort, and hang clothing and other articles after they are removed from the machines
• Clean and maintain laundry and dry-cleaning machines

Laundry and dry-cleaning workers ensure proper cleaning of clothing, linens, and other articles. They adjust machine settings for a given fabric or article, as determined by the cleaning instructions on each item of clothing.

When necessary, workers treat spots and stains on articles before washing or dry-cleaning. They monitor machines during the cleaning process and ensure that items are not lost or placed with items of another customer.

Sometimes, laundry and dry-cleaning workers interact with customers. They take the receipts, find the customer's clothing, take payment, make change, and do the cash register work that retail sales people do.

Some dry-cleaners offer alteration services. Often, sewers and tailors do these tasks, but some laundry and dry-cleaning workers do them as well. For more information, see the profile on sewers and tailors.

Water and wastewater treatment plant and system operators manage a system of machines, often through the use of control boards, to transfer or treat water or wastewater.

Water and wastewater treatment plant and system operators typically do the following:

• Add chemicals, such as ammonia, chlorine, or lime, to disinfect water or other liquids
• Inspect equipment on a regular basis
• Monitor operating conditions, meters, and gauges
• Collect and test water and sewage samples
• Record meter and gauge readings and operational data
• Operate equipment to purify and clarify water or to process or dispose of sewage
• Clean and maintain equipment, tanks, filter beds, and other work areas
• Stay current on U.S. Environmental Protection Agency regulations
• Ensure safety standards are met

It takes a lot of work to get water from natural sources--reservoirs, streams, and groundwater--into our taps. Similarly, it is a complicated process to convert the wastewater in our drains and sewers into a form that is safe to release into the environment.

The specific duties of plant operators depend on the type and size of the plant. In a small plant, one operator may be responsible for maintaining all of the systems. In large plants, multiple operators work the same shifts and are more specialized in their duties, often relying on computerized systems to help them monitor plant processes.

Occasionally, operators must work during emergencies. For example, weather conditions may cause large amounts of storm water or wastewater to flow into sewers, exceeding a plant's capacity. Emergencies also may be caused by malfunctions within a plant, such as chemical leaks or oxygen deficiencies. Operators are trained in emergency management procedures and use safety equipment to protect their health, as well as that of the public.

Water treatment plant and system operators work in water treatment plants. Fresh water is pumped from wells, rivers, streams, and reservoirs to water treatment plants, where it is treated and distributed to customers. Water treatment plant and system operators run the equipment, control the processes, and monitor the plants that treat water to make it safe to drink.

Wastewater treatment plant and system operators do similar work to remove pollutants from domestic and industrial waste. Used water, also known as wastewater, travels through sewage pipes to treatment plants where it is treated and either returned to streams, rivers, and oceans, or used for irrigation.

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:

• Travel to worksites
• Follow blueprints or other design specifications to install or repair HVACR systems
• Connect systems to fuel and water supply lines, air ducts, and other components
• Install electrical wiring and controls and test for proper operation
• Inspect and maintain customers' HVACR systems
• Test individual components to determine necessary repairs
• Repair or replace worn or defective parts

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.

Drywall and ceiling tile installers hang wallboards to walls and ceilings inside buildings. Tapers prepare the wallboards for painting, using tape and other materials. Many workers do both installing and taping.

Drywall installers typically do the following:

• Review design plans to minimize the number of cuts and waste of wallboard
• Measure the location of electrical outlets, plumbing, windows, and vents
• Cut drywall to the right size, using utility knives and power saws
• Fasten drywall panels to interior wall studs, using nails or screws
• Trim and smooth rough edges so boards join evenly

Ceiling tile installers typically do the following:

• Measure according to blueprints or drawings
• Nail or screw supports
• Put tiles or sheets of shock-absorbing materials on ceilings  
• Keep the tile in place with cement adhesive, nails, or screws

Tapers typically do the following:

• Prepare wall surface (wallboard) by patching nail holes
• Apply tape and use sealing compound to cover joints between wallboards
• Apply additional coats of sealing compound to create an even surface
• Sand all joints and holes to a smooth, seamless finish

Installers are also called framers or hangers. Tapers are also called finishers. Ceiling tile installers are sometimes called acoustical carpenters because they work with tiles that block sound.

Once wallboards are hung, workers use increasingly wider trowels to spread multiple coats of spackle over cracks, indentations, and any remaining imperfections. Some workers may use a mechanical applicator, a tool that spreads sealing compound on the wall joint while dispensing and setting tape at the same time.

To work on ceilings, drywall and ceiling tile installers and tapers may use mechanical lifts or stand on stilts, ladders, or scaffolds.

Drywall and ceiling tile installers hang wallboards to walls and ceilings inside buildings. Tapers prepare the wallboards for painting, using tape and other materials. Many workers do both installing and taping.

Drywall installers typically do the following:

• Review design plans to minimize the number of cuts and waste of wallboard
• Measure the location of electrical outlets, plumbing, windows, and vents
• Cut drywall to the right size, using utility knives and power saws
• Fasten drywall panels to interior wall studs, using nails or screws
• Trim and smooth rough edges so boards join evenly

Ceiling tile installers typically do the following:

• Measure according to blueprints or drawings
• Nail or screw supports
• Put tiles or sheets of shock-absorbing materials on ceilings  
• Keep the tile in place with cement adhesive, nails, or screws

Tapers typically do the following:

• Prepare wall surface (wallboard) by patching nail holes
• Apply tape and use sealing compound to cover joints between wallboards
• Apply additional coats of sealing compound to create an even surface
• Sand all joints and holes to a smooth, seamless finish

Installers are also called framers or hangers. Tapers are also called finishers. Ceiling tile installers are sometimes called acoustical carpenters because they work with tiles that block sound.

Once wallboards are hung, workers use increasingly wider trowels to spread multiple coats of spackle over cracks, indentations, and any remaining imperfections. Some workers may use a mechanical applicator, a tool that spreads sealing compound on the wall joint while dispensing and setting tape at the same time.

To work on ceilings, drywall and ceiling tile installers and tapers may use mechanical lifts or stand on stilts, ladders, or scaffolds.

Drywall and ceiling tile installers hang wallboards to walls and ceilings inside buildings. Tapers prepare the wallboards for painting, using tape and other materials. Many workers do both installing and taping.

Drywall installers typically do the following:

• Review design plans to minimize the number of cuts and waste of wallboard
• Measure the location of electrical outlets, plumbing, windows, and vents
• Cut drywall to the right size, using utility knives and power saws
• Fasten drywall panels to interior wall studs, using nails or screws
• Trim and smooth rough edges so boards join evenly

Ceiling tile installers typically do the following:

• Measure according to blueprints or drawings
• Nail or screw supports
• Put tiles or sheets of shock-absorbing materials on ceilings  
• Keep the tile in place with cement adhesive, nails, or screws

Tapers typically do the following:

• Prepare wall surface (wallboard) by patching nail holes
• Apply tape and use sealing compound to cover joints between wallboards
• Apply additional coats of sealing compound to create an even surface
• Sand all joints and holes to a smooth, seamless finish

Installers are also called framers or hangers. Tapers are also called finishers. Ceiling tile installers are sometimes called acoustical carpenters because they work with tiles that block sound.

Once wallboards are hung, workers use increasingly wider trowels to spread multiple coats of spackle over cracks, indentations, and any remaining imperfections. Some workers may use a mechanical applicator, a tool that spreads sealing compound on the wall joint while dispensing and setting tape at the same time.

To work on ceilings, drywall and ceiling tile installers and tapers may use mechanical lifts or stand on stilts, ladders, or scaffolds.