Definitions and Descriptions of Construction Trades and Related Workers

Asbestos/Insulation Workers

Boilermakers

Brickmasons, Blockmasons and Stonemasons

Carpenters

Carpet, Floor and Tile Installers and Finishers

Cement Masons, Concrete Finishers, Segmental Pavers and Terrazzo Workers

Drywall Installers, Ceiling Tile Installers and Tapers

Electricians

Elevator Installers and Repairers 

Glaziers

Ironworkers

Laborers

Millwrights

Operating Engineers

Painters and Paperhangers

Plasterers and Stucco Masons

Plumbers, Pipefitters and Steamfitters

Roofers

Sheet Metal Workers

Asbestos/Insulation Workers                                                                     Back to top

Nature of the Work:

Properly insulated buildings reduce energy consumption by keeping heat in during the winter and out in the summer.  Refrigerated storage rooms, vats, tanks, vessels, boilers, steam and hot water pipes are also insulated to prevent the wasteful transfer of heat.  Insulation workers install the materials used to insulate buildings and equipment.  Insulation workers cement, staple, wire, tape or spray insulation.  When covering a steam pipe, for example, insulation workers measure and cut sections of insulation to the proper length, stretch it open along a cut that runs the length of the material and slip it over the pipe.  They fasten the insulation with adhesive, staples, tape or wire bands.  Sometimes they wrap a cover of aluminum, plastic or canvas over it and cement or band the cover in place.  Insulation workers may screw on sheet metal around insulated pipes to protect the insulation from weather conditions or physical abuse.  When covering a wall or other flat surface, workers may use a hose to spray foam insulation onto a wire mesh.  The wire mesh provides a rough surface.  Workers may then install drywall or apply a final coat of plaster for a finished appearance.  In attics or exterior walls of uninsulated buildings, workers blow in loose-fill insulation.  A helper feeds a machine with fiberglass, cellulose or rock wool insulation while another worker blows the insulation with a compressor hose into the space being filled.  In new construction or major renovations, insulation workers staple fiberglass or rock wool batts to exterior walls and ceilings before drywall, paneling or plaster walls are put in place.  In making major renovations to old buildings or when putting new insulation around pipes and industrial machinery, insulation workers often must first remove the old insulation.  In the past, asbestos -- now known to cause cancer in humans -- was used extensively in walls and ceilings and for covering pipes, boilers and various industrial equipment.  Because of this danger, U.S. Environmental Protection Agency regulations require that asbestos be removed before a building undergoes major renovations or is demolished.  When asbestos is present, specially trained workers must remove the asbestos before insulation workers can install the new insulating materials.  Insulation workers use common handtools -- trowels, brushes, knives, scissors, saws, pliers and stapling guns. They use power saws to cut insulating materials, welding machines to join sheet metal or secure clamps and compressors to blow or spray insulation.

Boilermakers                                                                                                 Back to top

Nature of the Work:

Boilermakers and boilermaker mechanics make, install and repair boilers, vats and other large vessels that hold liquids and gases.  Boilers supply steam to drive huge turbines in electric power plants and to provide heat and power in buildings, factories and ships.  Tanks and vats are used to process and store chemicals, oil, beer and hundreds of other products.  Boilers and other high-pressure vessels are usually made in sections, by casting each piece out of molten iron or steel.  Manufactures are increasingly automating this process to increase the quality of these vessels.  Boiler sections are then welded together, often using automated orbital welding machines, which make more consistent welds than are possible by hand.  Small boilers may be assembled in the manufacturing plant; larger boilers usually are assembled on-site.  Following blueprints, boilermakers locate and mark reference points on the boiler foundation, using straightedges, squares, transits and tape measures.  Boilermakers attach rigging and signal crane operators to lift heavy frame and plate sections and other parts into place.  They align sections, using plumb bobs, levels, wedges and turnbuckles.  Boilermakers use hammers, files, grinders and cutting torches to remove irregular edges so that the edges fit properly. These edges are then bolted or welded together.  Boilermakers align and attach water tubes, stacks, valves, gauges and other parts, and then test complete vessels for leaks or other defects.  They also install refractory brick and other heat-resistant materials in fireboxes or pressure vessels.  Usually, they assemble large vessels temporarily in a fabrication shop to ensure a proper fit before final assembly on the permanent site.  Because boilers last a long time --35 years or more -- boilermakers regularly maintain them and update components, such as burners and boiler tubes, to increase efficiency. 

Boilermaker mechanics maintain and repair boilers and similar vessels.  They inspect tubes, fittings, valves, controls and auxiliary machinery as well as clean or supervise the cleaning of boilers using scrapers, wire brushes and cleaning solvents.  They repair or replace defective parts, using hand and power tools, gas torches and welding equipment. Boilermaker mechanics also operate metalworking machinery to repair or make parts.  They also dismantle leaky boilers, patch weak spots with metal stock, replace defective sections and strengthen joints.

Brickmasons, Blockmasons and Stonemasons                                      Back to top

Nature of the Work:

Brickmasons, blockmasons and stonemasons work in closely related trades creating attractive, durable surfaces and structures.  The work varies in complexity, from laying a simple masonry walkway to installing an ornate exterior on a high-rise building.  Brickmasons and blockmasons, who often are referred to simply as bricklayers, build and repair walls, floors, partitions, fireplaces, chimneys and other structures with brick, precast masonry panels, concrete block and other masonry materials.  Additionally, brickmasons specialize in installing firebrick linings in industrial furnaces. 

Stonemasons build stonewalls, as well as set stone exteriors and floors.  They work with two types of stone -- natural cut, such as marble, granite and limestone and artificial stone made from concrete, marble chips or other masonry materials.  Stonemasons usually work on nonresidential structures, such as houses of worship, hotels and office buildings.  When building a structure, brickmasons use one of two methods -- the corner lead or the corner pole.  Using the corner lead method, they begin by constructing a pyramid of bricks at each corner, called a lead.  After the corner leads are complete, less experienced brickmasons fill in the wall between the corners using a line from corner to corner to guide each course, or layer, of brick.  Due to the precision needed, corner leads are time consuming to erect and require the skills of experienced bricklayers.  Because of the expense associated with building corner leads, most brickmasons use corner poles, also called masonry guides, that enable them to build an entire wall at the same time.  They fasten and stretch a line between them that serves as a guide for each course of brick.  Brickmasons then spread a bed of mortar (a cement, sand and water mixture) with a trowel (a flat, bladed metal tool with a handle), place the brick on the mortar bed, press and tap the brick into place.  Depending on blueprint specifications, brickmasons either cut brick with a hammer and chisel or saw them to fit around windows, doors and other openings.  Mortar joints are then finished with jointing tools for a sealed, neat, uniform appearance.  Although brickmasons usually use steel supports, or lintels, at window and door openings, they sometime build brick arches instead, which support and enhance the beauty of the brickwork.  Stonemasons often work from a set of drawings, in which each stone has been numbered for identification.  Helpers may locate and carry these prenumbered stones to the masons.  A derrick operator using a hoist may be needed to lift large stone pieces into place.  When building a stone wall, masons set the first course of stones into a shallow bed of mortar.  They then align the stones with wedges, plumblines and levels and then adjust them into position with a hard rubber mallet.  Masons continue to build the wall by alternating layers of mortar and courses of stone.  As the work progresses, masons remove the wedges, fill the joints between stones and use a pointed metal tool called a tuck pointer to smooth the mortar to an attractive finish.  To hold large stones in place, stonemasons attach brackets to the stone and weld or bolt these brackets to anchors in the wall.  Finally, masons wash the stone with a cleansing solution to remove stains and dry mortar.  When setting stone floors, which often consist of large and heavy pieces of stone, masons first use a trowel to spread a layer of damp mortar over the surface to be covered.  Using crowbars and hard rubber mallets for aligning and leveling, they then set the stone in the mortar bed.  To finish, workers fill the joints and wash the stone slabs.  Masons use a special hammer and chisel to cut stone.  They cut stone along the grain to make various shapes and sizes. Valuable pieces of stone are often cut with a saw that has a diamond blade.  Some masons specialize in setting marble, which in many respects is similar to setting large pieces of stone.  Brickmasons and stonemasons also repair imperfections and cracks and replace broken or missing masonry units in walls and floors.  Most nonresidential buildings are now built with walls made of concrete block, brick veneer, stone, granite, marble, tile or glass. 

In the past, brickmasons and blockmasons doing nonresidential interior work, mostly built block partition walls and elevator shafts.  Now, these workers must be more versatile and work with many materials.  For example, some brickmasons and blockmasons now install structural insulated wall panels and masonry accessories used in many high-rise buildings.  Refractory masons are brickmasons who specialize in installing firebrick and refractory tile in high-temperature boilers, furnaces, cupolas, ladles and soaking pits in industrial establishments.  Most of these work in steel mills, where molten materials flow on refractory beds from furnaces to rolling machines.

Carpenters                                                                                                      Back to top

Nature of the Work:

Carpenters are involved in many different kinds of construction activity.  They cut, fit and assemble wood and other materials for the construction of buildings, highways, bridges, docks, industrial plants, boats, ships and many other structures.  Carpenters also build doors or brattices (ventilation walls or partitions) in underground passageways to control the proper circulation of air through these passageways and to worksites.  Carpenters’ duties vary by type of employer.  Builders are increasingly using specialty trade contractors who, in turn, hire carpenters who specialize in just one or two activities.  Some of these activities are setting forms for concrete construction, erecting scaffolding or doing finishing work, such as installing interior and exterior trim.  However, a carpenter directly employed by a general building contractor must often perform a variety of the tasks associated with new construction, such as framing walls and partitions, putting in doors and windows, building stairs, laying hardwood floors and hanging kitchen cabinets.  Because local building codes often dictate where certain materials can be used, carpenters must know these regulations.  Each carpentry task is somewhat different, but most tasks involve the same basic steps. 

Working from blueprints or instructions from supervisors, carpenters first do the layout-measuring, marking and arranging materials.  They cut and shape wood, plastic, fiberglass or drywall using hand and power tools, such as chisels, planes, saws, drills and sanders.  They then join the materials with nails, screws, staples or adhesives.  In the final step, carpenters check the accuracy of their work with levels, rules, plumb bobs and framing squares and make any necessary adjustments. 

When working with prefabricated components such as stairs or wall panels, the carpenter’s task is somewhat simpler than above because it does not require as much layout work or the cutting and assembly of as many pieces.  Prefabricated components are designed for easy and fast installation and generally can be installed in a single operation.  Carpenters who remodel homes and other structures must be able to do all aspects of a job and not just one task.  Thus, individuals with good basic overall training are at a distinct advantage because they can switch from residential building to commercial construction or remodeling work, depending on which offers the best work opportunities.  Carpenters employed outside the construction industry perform a variety of installation and maintenance work.  They may replace panes of glass, ceiling tiles and doors, as well as repair desks, cabinets and other furniture.  Depending on the employer, carpenters install partitions, doors and windows, change locks and repair broken furniture.  In manufacturing firms, carpenters may assist in moving or installing machinery.

Carpet, Floor and Tile Installers and Finishers                                       Back to top

Nature of the Work:

Carpet, tile and other types of floor covering not only serve an important basic function in buildings but their decorative qualities also contribute to the appeal of the buildings.  Carpet, floor and tile installers and finishers lay these floor coverings in homes, offices, hospitals, stores, restaurants and many other types of buildings.  Tile is also installed on walls and ceilings. 

Before installing carpet, carpet installers first inspect the surface to be covered to determine its condition and if necessary, correct any imperfections that could show through the carpet or cause the carpet to wear unevenly.  They must measure the area to be carpeted and plan the layout, keeping in mind expected traffic patterns and placement of seams for best appearance and maximum wear.  When installing wall-to-wall carpet without tacks, installers first fasten a tackless strip to the floor, next to the wall.  They then install the padded cushion or underlay.  Next, they roll out, measure, mark and cut the carpet, allowing for 2 to 3 inches of extra carpet for the final fitting.  Using a device called a “knee kicker,” they position the carpet, stretching it to fit evenly on the floor and snugly against each wall and door threshold.  They then rough cut the excess carpet.  Finally, using a power stretcher, they stretch the carpet, hooking it to the tackless trip to hold it in place.  The installer then finishes the edges using a wall trimmer.  Because most carpet comes in 12-foot widths, wall-to-wall installations require installers to tape or sew sections together for large rooms.  They join the seams by sewing them with a large needle and special thread or by using heat tape -- a special plastic tape made to join seams when activated by heat.  On special upholstery work, such as stairs, carpet may be held in place with staples.  Also, in commercial installations, carpet is often glued directly to the floor or to padding that has been glued to the floor.  Carpet installers use handtools such as hammers, drills, staple guns, carpet knives and rubber mallets.  They also may use carpet-laying tools, such as carpet shears, knee kickers, wall trimmers, loop pile cutters, heat irons and power stretchers.  Floor installers or floor layers, apply block, strips or sheets of shock-absorbing, sound-deadening or decorative coverings to floors and cabinets using rollers, knives, trowels, sanding machines and other tools.  Some floor covering materials are designed to be purely decorative.  Other materials have more specialized purposes, such as to deaden sound, to absorb shock or to create airtight environments.  Before installing the floor, floor layers inspect the surface to be covered, and if necessary, correct any imperfections in order to start with a smooth, clean foundation.  They measure and cut floor covering materials, such as rubber, vinyl, linoleum or cork and any foundation material, such as felt, according to designated blueprints.  Next, they may nail or staple a wood underlayment to the surface or may use an adhesive to cement the foundation material to the floor; the foundation helps to deaden sound and prevents the top floor covering from wearing at board joints.  Finally, floor layers install the top covering.  They join sections of sheet covering by overlapping adjoining edges and cutting through both layers with a knife to form a tight joint. 

Floor sanders and finishers scrape and sand wooden floors to smooth surfaces using floor-scrapers and floor-sanding machines.  They then inspect the floor for smoothness and remove excess glue from joints using a knife, scraper or wood chisel and may sand wood surfaces by hand using sandpaper.  Finally, they apply coats of finish. 

Tile installers, tilesetters and marble setters apply hard tile and marble to floors, walls, ceilings and roof decks.  Tile is durable, impervious to water and easy to clean, making it a popular building material in hospitals, tunnels, lobbies of buildings, bathrooms and kitchens.  To set tile, which generally ranges in size from 1 inch to 12 or more inch squares, tilesetters use cement or “mastic,” a very sticky paste.  When using cement, tilesetters nail a support of metal mesh to the wall or ceiling to be tiled.  They use a trowel to apply a cement mortar called a “scratch coat” onto the metal screen and scratch the surface of the soft mortar with a small tool, similar to a rake.  After the scratch coat has dried, tilesetters apply another coat of mortar to level the surface and apply mortar to the back of the tile and place it onto the surface.  To set tile in mastic or a cement adhesive, called “thin set,” tilesetters need a flat, solid surface such as drywall, concrete, plaster or wood.  They use a tooth-edged trowel to spread mastic on the surface or apply cement adhesive and then properly position the tile.  Because tile varies in color, shape and size, workers sometimes prearrange tiles on a dry floor according to a specified design.  This allows workers to examine the pattern and make changes.  In order to cover all exposed areas, including corners and around pipes, tubs and wash basins, tilesetters cut tiles to fit with a machine saw or a special cutting tool.  Once the tile is placed, they gently tap the surface with their trowel handle or a small block of wood to seat the tiles evenly.  When the cement or mastic has set, tilesetters fill the joints with “grout,” which is a very fine cement.  They then scrape the surface with a rubber-edged device called a grout float or a grouting trowel to dress the joints and remove excess grout.  Before the grout sets, they finish the joints with a damp sponge for a uniform appearance. 

Tile finishers help some tilesetters by supplying and mixing construction materials and doing other tasks such as applying grout and cleaning installed tile. 

Marble setters cut and set marble slabs in floors and walls of buildings.  They trim and cut marble to specified size using a power wet saw, other cutting equipment or handtools.  After setting the marble in place, they polish the marble to a high luster using power tools or by hand.  

Cement Masons, Concrete Finishers, Segmental Pavers and Terrazzo Workers Back to top

Nature of the Work:

Cement masons, concrete finishers and terrazzo workers all work with concrete, one of the most common and durable materials used in construction.  Once set, concrete -- a mixture of Portland cement, sand, gravel and water -- becomes the foundation for everything from decorative patios and floors to huge dams or miles of roadways.  Cement masons and concrete finishers place and finish the concrete.  They also may color concrete surfaces, expose aggregate (small stones) in walls and sidewalks or fabricate concrete beams, columns and panels. In preparing a site for placing concrete, cement masons first set the forms for holding the concrete and properly align them.  They then direct the casting of the concrete and supervise labors who use shovels or special tools to spread it.  Masons then guide a straightedge back and forth across the top of the forms to “screed,” or level the freshly placed concrete.  Immediately after leveling the concrete, masons carefully smooth the concrete surface with a “bull float,” a long-handled tool about 8 inches by 48 inches that covers the coarser materials in the concrete and brings a rich mixture of fine cement paste to the surface.  After the concrete has been leveled and floated, concrete finishers press an edger between the forms and the concrete and guide it along the edge and the surface.  This produces slightly rounded edges and helps prevent chipping or cracking.  They use a special tool called a “groover” to make joints or grooves at specific intervals that help control cracking.  Next, concrete finishers trowel the surface using either a powered or hand trowel, a small smooth, rectangular metal tool.  Sometimes, cement masons perform all the steps of laying concrete, including the finishing.  As the final step, masons retrowel the concrete surface back and forth with powered and hand trowels to create a smooth finish.  For a coarse, nonskid finish, masons brush the surface with a broom or stiff-bristled brush.  For a pebble finish, they embed small gravel chips into the surface.  They then wash any excess cement from the exposed chips with a mild acid solution.  For color, they use colored premixed concrete.  On concrete surfaces that will remain exposed after the forms are stripped, such as columns, ceilings and wall panels, cement masons cut away high spots and loose concrete with a hammer and chisel, fill any large indentations with a Portland cement paste and smooth the surface with a carborundum stone.  Finally, they coat the exposed area with a rich Portland cement mixture, using either a special tool or a coarse cloth to rub the concrete to a uniform finish.  Throughout the entire process, cement masons must monitor how the wind, heat or cold affects the curing of the concrete.  They must have a thorough knowledge of concrete characteristics so that by using sight and touch, they can determine what is happening to the concrete and take measures to prevent defects. 

Segmental pavers lay out, cut and install pavers, which are flat pieces of masonry usually made from compacted concrete or brick.  Pavers are used to pave paths, patios, playgrounds, driveways and steps.  They are manufactured in various textures and often interlock together to form an attractive pattern.  Segmental pavers first prepare the site by removing the existing pavement or existing soil.  They grade the soil to the proper depth and determine the amount of base material that is needed, which depends on the local soil conditions.  They then install and compact the base material, a granular material that compacts easily, and lay the pavers from the center out, so that any trimmed pieces will be on the outside rather than in the center.  Then they install edging materials to prevent the pavers from shifting and fill the spaces between the pavers with dry sand. 

Terrazzo workers create attractive walkways, floors, patios and panels by exposing marble chips and other fine aggregates on the surface of finished concrete.  Much of the preliminary work of terrazzo workers is similar to that of cement masons.  Attractive, marble-chip terrazzo requires three layers of materials.  First, cement masons or terrazzo workers build a solid, level concrete foundation that is 3 inches to 4 inches deep.  After the forms are removed from the foundation, workers add a 1-inch layer of sandy concrete.  Before this layer sets, terrazzo workers partially embed metal divider strips in the concrete wherever there is to be a joint or change of color in the terrazzo.  For the final layer, terrazzo workers blend and place into each of the panels, a fine marble chip mixture that may be color pigmented.  While the mixture is still wet, workers toss additional marble chips of various colors into each panel and roll a lightweight roller over the entire surface. When the terrazzo is thoroughly dry, helpers grind it with a terrazzo grinder, which is somewhat like a floor polisher, only much heavier.  Slight depressions left by the grinding are filled with a matching grout material and hand-toweled for a smooth, uniform surface.  Terrazzo workers then clean, polish and seal the dry surface for a lustrous finish.

Drywall Installers, Ceiling Tile Installers and Tapers                            Back to top

Nature of the Work:

Drywall consists of a thin layer of gypsum between two layers of heavy paper.  It is used for walls and ceilings in most buildings today because it is both faster and cheaper to install than plaster.  There are two kinds of drywall workers -- installers and tapers -- although many workers do both types of work.  Installers, also called applicators, fasten drywall panels to the inside framework of residential houses and other buildings.  Tapers, or finishers, prepare these panels for painting by taping and finishing joints and imperfections.  Because drywall panels are manufactured in standard sizes, usually 4 feet by 8 or 12 feet, drywall installers must measure, cut and fit some pieces around doors and windows.  They also saw or cut holes in panels for electrical outlets, air-conditioning units and plumbing.  After making these alterations, installers may glue, nail or screw the wallboard panels to the wood or metal framework.  Because drywall is heavy and cumbersome, a helper generally assists the installer in positioning and securing the panel.  A lift is often used when placing ceiling panels.  After the drywall is installed, tapers fill joints between panels with a joint compound.  Using the wide, flat tip of a special trowel, they spread the compound into and along each side of the joint with brush-like strokes.  They immediately use the trowel to press a paper tape, used to reinforce the drywall and to hide imperfections, into the wet compound and to smooth away excess material.  Nail and screw depressions are also covered with this compound, as are imperfections caused by the installation of air-conditioning vents and other fixtures.  On large commercial projects, finishers may use automatic taping tools that apply the joint compound and tape in one step.  Tapers apply second and third coats of the compound, sanding the treated areas after each coat to make them as smooth as the rest of the wall surface.  This results in a very smooth and almost perfect surface.  Some tapers apply textured surfaces to walls and ceilings with trowels, brushes or spray guns. 

Ceiling tile installers or acoustical carpenters, apply or mount acoustical tiles or blocks, strips or sheets of shock-absorbing materials to ceilings and walls of buildings to reduce reflection of sound or to decorate rooms.  First, they measure and mark the surface according to blueprints and drawings.  They then nail or screw moldings to the wall to support and seal the joint between the ceiling tile and the wall.  Finally, they mount the tile, either by applying a cement adhesive to the back of the tile and then pressing the tile into place or by nailing, screwing, stapling or wire-tying the lath directly to the structural framework. 

Also included in this occupation are lathers.  Lathers fasten metal or rockboard lath to walls, ceilings and partitions of buildings.  Lath forms the support base for plaster, fireproofing or acoustical materials.  At one time, lath was made of wooden strips.  Now, lathers work mostly with wire, metal mesh or rockboard lath.  Metal lath is used where the plaster application will be exposed to weather or water or for curved or irregular surfaces for which drywall is not a practical material.  Using hand tools and portable power tools, latherers nail, screw, staple or wire-tie the lath directly to the structural framework.

Electricians                                                                                                     Back to Top

Nature of the Work:

Electricity is essential for light, power, air-conditioning and refrigeration.  Electricians install, connect, test and maintain electrical systems for a variety of purposes, including climate control, security and communications.  They may also install and maintain the electronic controls for machines in business and industry.  Although most electricians specialize in either construction or maintenance, a growing number do both.  Electricians work with blueprints when they install electrical systems in factories, office buildings, homes and other structures.  Blueprints indicate the locations of circuits, outlets, load center, panel boards and other equipment.  Electricians must follow the National Electric Code and comply with state and local building codes when they install these systems.  In factories and offices, they first place conduit (pipe or tubing) inside designated partitions, walls or other concealed areas.  They also fasten to the wall, small metal or plastic boxes that will house electrical switches and outlets.  They then pull insulated wires or cables through the conduit to complete circuits between these boxes.  In lighter construction, such as residential, plastic-covered wire is usually used instead of conduit.  Regardless of the type of wire used, electricians connect it to circuit breakers, transformers or other components.  They join the wires in boxes with various specially designed connectors.  After they finish the wiring, they use testing equipment, such as ohmmeters, voltmeters and oscilloscopes, to check the circuits for proper connections, ensuring electrical compatibility and safety of components.  In addition to wiring a building’s electrical system, electricians may install coaxial or fiber optic cable for computers and other telecommunications equipment.  A growing number of electricians install telephone systems, computer wiring and equipment, streetlights, intercom systems, fire alarm and security systems.  They may also connect motors to electrical power and install electronic controls for industrial equipment. Maintenance work varies greatly, depending on where the electrician is employed.  Electricians who specialize in residential work may rewire a home and replace an old fuse box with a new circuit breaker to accommodate additional appliances.  Those who work in large factories may repair motors, transformers, generators and electronic controllers on machine tools and industrial robots.  Those in office buildings and small plants may repair all types of electrical equipment. 

Maintenance electricians spend much of their time in preventive maintenance.  They periodically inspect equipment and locate and correct problems before breakdowns occur.  Electricians may also advise management on whether continued operation of equipment could be hazardous.  When needed, they install new electrical equipment.  When breakdowns occur, they must make the necessary repairs as quickly as possible in order to minimize inconvenience.  Electricians may replace items such as circuit breakers, fuses, switches, electrical and electronic components or wire.  When working with complex electronic devices, they may work with engineers, engineering technicians as well as industrial machinery installation, repair and maintenance workers.  Electricians use handtools such as screwdrivers, pliers, knives and hacksaws.  They also use power tools and testing equipment such as oscilloscopes, ammeters and test lamps.

Elevator Installers and Repairers                                                  Back to top

Nature of the Work:

Elevator installers and repairers -- also called elevator constructors or elevator mechanics -- assemble, install and replace elevators, escalators, dumbwaiters, moving walkways and similar equipment in new and old buildings.  Once the equipment is in service, they maintain and repair it as well.  They are also responsible for modernizing older equipment.  To install, repair and maintain modern elevators, which are almost all electronically controlled, elevator installers and repairers must have a thorough knowledge of electronics, electricity and hydraulics.  Many elevators are controlled with microprocessors, which are programmed to analyze traffic conditions in order to dispatch elevators in the most efficient manner.  With these computer controls, it is possible to get the greatest amount of service with the least number of cars.  When installing a new elevator, installers and repairers begin by studying blueprints to determine the equipment needed to install rail, machinery, car enclosures, motors, pumps, cylinders and plunger foundations.  Once this has been done, they begin equipment installation.  Working on scaffolding or platforms, installers bolt or weld steel rails to the walls of the shaft to guide the elevator.  Elevator installers put in electrical wires and controls by running tubing, called conduit, along a shaft’s walls from floor to floor.  Once it is in place, mechanics pull plastic-covered electrical wires through the conduit.  They then install electrical components and related devices required at each floor and at the main control panel in the machine room.  Installers bolt or weld together the steel frame of an elevator car at the bottom of the shaft, install the car’s platform, walls and doors, and attach guide shoes and rollers to minimize the lateral motion of the car as it travels through the shaft.  They also install the outer doors and doorframes at the elevator entrances on each floor.  For cabled elevators, these workers install geared or gearless machines with a traction drive wheel that guides and moves heavy steel cables connected to the elevator car and counterweight.  (The counterweight moves in the opposite direction from the car and balances most of the weight of the car to reduce the weight that the elevator’s motor must lift.)  Elevator installers also install elevators in which a car sits on a hydraulic plunger that is driven by a pump.  The plunger pushes the elevator car up from underneath, similar to a lift in an auto service station.  Installers and repairers also install escalators.  They put in place the steel framework, the electrically powered stairs and tracks and install associated motors and electrical wiring.  In addition to elevators and escalators, they may also install devices such as dumbwaiters and material lifts, which are similar to elevators in design, as well as moving walkways, stair lifts and wheelchair lifts. 

The most highly skilled elevator installers and repairers, called “adjusters,” specialize in fine-tuning all the equipment after installation.  Adjusters make sure that an elevator is working according to specifications, such as stopping correctly at each floor within a specified time.  Once an elevator is operating properly, it must be maintained and serviced regularly to keep it in safe working condition.  Elevator installers and repairers generally do preventive maintenance, such as oiling and greasing moving parts, replacing worn parts, testing equipment with meters and gauges and adjusting equipment for optimal performance.  They also troubleshoot and may be called in to do emergency repairs.  A service crew usually handles major repairs such as replacing cables, elevator doors or machine bearings.  This may require the use of cutting torches or rigging equipment tools that an elevator repairer normally would not carry.  Service crews also do major modernization and alteration work, such as moving and replacing electrical motors, hydraulic pumps and control panels.  Elevator installers and repairers usually specialize in installation, maintenance or repair work.  Maintenance and repair workers generally need more knowledge of electricity and electronics than installers do, because a large part of maintenance and repair work is troubleshooting.  Similarly, adjusters need a thorough knowledge of electricity, electronics and computers to ensure that newly installed elevators operate properly. 

Glaziers                                                                                      Back to top

Nature of the Work:

Glass serves many uses in modern buildings.  Insulated and specially treated glass keeps in warmed or cooled air and provides good condensation and sound control qualities; tempered and laminated glass makes doors and windows more secure.  In large commercial buildings, glass panels give office buildings a distinctive look while reducing the need for artificial lighting.  The creative use of large windows, glass doors, skylights and sunroom additions makes homes bright, airy and inviting. 

Glaziers are responsible for selecting, cutting, installing, replacing and removing all types of glass.  They generally work on one of several types of projects.  Residential glazing involves work such as replacing glass in home windows.  Installing glass mirrors, shower doors and bathtub enclosures and fitting glass for tabletops and display cases.  On commercial interior projects, glaziers install items such as heavy, often etched, decorative room dividers or security windows.  Glazing projects also may involve replacement of storefront windows for establishments such as supermarkets, auto dealerships or banks.  In the construction of large commercial buildings, glaziers build metal framework extrusions and install glass panels or curtain walls. 

Besides working with glass, glaziers also may work with plastics, granite, marble and similar materials used as glass substitutes.  They may mount steel and aluminum sashes or frames and attach locks and hinges to glass doors.  For most jobs, the glass is precut and mounted in frames at a factory or a contractor’s shop.  It arrives at the jobsite ready for glaziers to position and secure it in place.  They may use a crane or hoist with suction cups to lift large, heavy pieces of glass.  They then gently guide the glass into position by hand.  Once glaziers have the glass in place, they secure it with mastic, putty or other paste-like cement, or with bolts, rubber gaskets, glazing compound, metal clips, or metal or wood moldings.  When they secure glass using a rubber gasket -- a thick, molded rubber half-tube with a split running its length -- they first secure the gasket around the perimeter within the opening, then set the glass into the split side of the gasket, causing it to clamp to edges and hold the glass firmly in place.  When they use metal clips and wood moldings, glaziers first secure the molding to the opening, place the glass in the molding and then force spring-like metal clips between the glass and the molding.  The clips exert pressure and keep the glass firmly in place.  When a glazing compound is used, glaziers first spread it neatly against and around the edges of the molding on the inside of the opening.  Next, they install the glass.  Pressing it against the compound on the inside molding, workers screw or nail outside molding that loosely holds the glass in place.  To hold it firmly, they pack the space between the molding and glass with glazing compound and then trim any excess material with a glazing knife.  For some jobs, the glazier must cut the glass manually at the jobsite.  To prepare the glass for cutting, glaziers rest it either on edge on a rack, or “A-frame,” or flat against a cutting table.  They then measure and mark the glass for the cut.  Glaziers cut glass with a special tool that has a small, very hard metal wheel.  Using a straightedge as a guide, the glazier presses the cutter’s wheel firmly on the glass, guiding and rolling it carefully to make a score just below the surface.  To help the cutting tool move smoothly across the glass, workers brush a thin layer of oil along the line of the intended cut or dip the cutting tool in oil.  Immediately after cutting, the glazier presses on the shorter end of the glass to break it cleanly along the cut. 

Glaziers also replace or repair broken or pitted windshields and window glass on automobiles and other vehicles.  They first remove the broken glass, which may involve cutting it free from the adhesive holding it down.  They then install the glass in the vehicle, often using a special adhesive.  They may also weatherproof the window or windshield and prevent it from rattling by installing rubber strips around the sides of the glass.  In addition to handtools such as glass cutters, suction cups and glazing knives, glaziers use power tools such as saws, drills, cutters and grinders.  An increasing number of glaziers use computers in the shop or at the jobsite to improve their layout work and reduce the amount of glass that is wasted.

Ironworkers                                                                                Back to top

Nature of the Work:

Builders use materials made from iron, steel, aluminum, fiberglass or precast concrete to construct highways, bridges, office and other large buildings and power transmission towers.  These structures have frames made of steel columns, beams and girders.  In addition, reinforced concrete, concrete containing steel bars or wire fabric, is an important material in buildings, bridges and other structures, as the steel gives the concrete additional strength.  Moreover, metal stairways, catwalks, floor gratings, ladders, window frames, lampposts, railings, fences and decorative ironwork increase the functionality and attractiveness of these structures.  Structural and reinforcing iron and metalworkers fabricate, assemble and install these products.  They also repair, renovate and maintain older buildings and structures, such as manufacturing plants, highways and bridges.  Even though the primary metal involved in this work is steel, workers are often known as ironworkers. 

Before construction can begin, ironworkers must erect steel frames and assemble the cranes and derricks that move structural steel, reinforcing bars, buckets of concrete, lumber and other materials and equipment around the construction site.  The structural metal arrives at the construction site in sections.  Once there, it is lifted into position by a crane.  Ironworkers then connect the sections and set the cables to do the hoisting.  Once this job has been completed, workers begin to connect steel columns, beams and girders according to blueprints and instructions from supervisors and superintendents.  Structural steel, reinforcing rods and ornamental iron generally come to the construction site ready for erection, cut to the proper size, with holes drilled for bolts and numbered for assembly.  Ironworkers at the construction site unload and stack the prefabricated steel so that it can be hoisted easily when needed.  To hoist the steel, metalworkers attach cables from a crane or derrick.  One worker directs the hoist operator with hand signals.  Another worker holds a rope (tag line) attached to the steel to prevent it from swinging.  The crane or derrick hoists steel into place in the framework, where several workers, using spud wrenches, position the steel with connecting bars and jacks.  Workers using drift pins or the handle of a spud wrench, a long wrench with a pointed handle, align the holes in the steel with the holes in the framework.  They then temporarily bolt the piece in place, check vertical and horizontal alignment with plumb bobs, laser equipment, transits or levels and then bolt or weld the piece permanently in place. 

Reinforcing iron and rebar workers set the bars in the forms that hold concrete, following blueprints showing the location, size and number of reinforcing bars (rebar).  They then fasten the bars together by tying wire around them with pliers.  When reinforcing floors, workers place blocks under the rebar to hold the bars off the deck.  Although their materials usually arrive ready to use, ironworkers occasionally must cut bars with metal shears or acetylene torches, bend them by hand or machine or weld them with arc-welding equipment.  Some concrete is reinforced with welded wire fabric.  Using hooked rods, workers cut and fit the fabric and while a concrete crew places the concrete, metalworkers properly position the fabric in the concrete. 

Post-tensioning is another technique used in reinforcing concrete. In this technique, workers substitute cables for reinforcing bars.  When the concrete is poured, the ends of the cables are left exposed.  After the concrete dries, ironworkers tighten the cable.  Post-tensioning allows designers to create larger open areas in a building because supports can be placed further apart.  This technique is commonly employed in parking garages and arenas.  Ornamental ironworkers install elevator shafts, stairs, curtain walls (the nonstructural walls and window frames of many large buildings) and other ornamentation pieces after the structure of the building has been completed.  As they hoist pieces into position, ornamental ironworkers check that the pieces are properly fitted and aligned before bolting, brazing or welding them for a secure fit.

Laborers                                                                                     Back to top

Nature of the Work:

Construction laborers perform a wide range of physically demanding tasks involving building and highway construction, tunnel and shaft excavation, hazardous waste removal and demolition.  Although the term “laborer” implies work that requires relatively low skill or training, many tasks that these workers perform require a fairly high level of training and experience.  Construction laborers clean and prepare construction sites to eliminate possible hazards, dig trenches, mix and place concrete and set braces to support the sides of excavations.  They load, unload, identify and distribute building materials to the appropriate location according to project plans and specifications on building construction projects.  Construction laborers also tend machines.  For example, they may mix concrete using a portable mixer or tend a machine that pumps concrete, grout, cement, sand plaster or stucco through a spray gun for application to ceiling and walls.  Construction labors may sometimes help other craft workers including carpenters, plasters and masons.  At heavy and highway construction sites, construction laborers clear and prepare highway work zones and rights of way, install traffic barricades, cones and markers, and control traffic passing near, in, and around work zones.  They also install sewer, water and storm drainpipes, build manholes and lay cement and asphalt on roads. 

At hazardous waste removal sites, construction laborers prepare the site and safely remove asbestos, lead, radioactive waste and other hazardous materials.  They operate, read and maintain air monitoring and other sampling devices in confined and/or hazardous environments.  They also safely sample, identify, handle, pack and transport hazardous and/or radioactive materials and clean and decontaminate equipment, buildings and enclosed structures.  Other highly specialized tasks include operating laser guidance equipment to place pipes, operating air and pneumatic drills and transporting and setting explosives for tunnel, shaft and road construction.  Construction laborers operate a variety of equipment including pavement breakers,  jackhammers, earth tampers, concrete, mortar and plaster mixers, electric and hydraulic boring machines, torches, small mechanical hoists, laser beam equipment and surveying and measuring equipment.  They operate pipe-laying machinery and use computers and other high-tech input devices to control robotic pipe cutters and cleaners.  To perform their jobs effectively, construction laborers must be familiar with the duties of other craft workers as well as the materials, tools and machinery they use.  Construction laborers often work as part of a team with other skilled craft workers, jointly carrying out assigned construction tasks.  At other times, construction laborers may work alone, reading and interpreting instructions, plans and specifications with little or no supervision.  While most construction laborers tend to specialize in a type of construction such as highway or tunnel construction, they are skilled generalists who perform many different tasks during all stages of construction (such as in tunnels) or in demolition and are more likely to specialize in only those areas.

Millwrights                                                                                  Back to top

Nature of the Work:

When production workers encounter problems with the machines they operate, they call industrial machinery installation, repair and maintenance workers.  These workers include industrial machinery mechanics, millwrights, general maintenance and repair and machinery maintenance workers.  Their work is important not only because an idle machine will delay production but also because a machine that is not properly repaired and maintained may damage the final product or injure the operator.  Industrial machinery mechanics repair, install, adjust or maintain industrial production and processing machinery or refinery and pipeline distribution systems.  Millwrights install, dismantle or move machinery and heavy equipment according to layout plans, blueprints or other drawings.  General maintenance and repair workers perform work involving the skills of two or more maintenance or craft occupations to keep machines, mechanical equipment or the structure of an establishment in repair.  Machinery maintenance workers lubricate machinery, change parts or perform other routine machinery maintenance.  Much of the work begins when the machinery arrives at the job site.  New equipment must be unloaded, inspected and moved into position.  To lift and move light machinery, industrial machinery installation, repair and maintenance workers use rigging and hoisting devices, such as pulleys and cables.  In other cases, they require the assistance of hydraulic lift truck or crane operators to position the machinery.  Because industrial machinery installation, repair, and maintenance workers often decide which device to use for moving machinery, they must know the load-bearing properties of ropes, cables, hoists and cranes.  Industrial machinery installation, repair and maintenance workers consult with production managers and others to determine the optimal placement of machines in a plant.  In some instances, this placement requires building a new foundation.  Industrial machinery installation, repair and maintenance workers either prepare the foundation themselves or supervise its construction, so they must know how to read blueprints and work with building materials, such as concrete, wood and steel.  When assembling machinery, industrial machinery installation, repair and maintenance workers fit bearings, align gears and wheels, attach motors and connect belts, according to the manufacturer’s blueprints and drawings.  Precision leveling and alignment are important in the assembly process; industrial machinery installation, repair and maintenance workers must have good mathematical skills so they can measure angles, material thickness and small distances with tools such as squares, calipers and micrometers.  When a high level of precision is required, devices such as lasers and ultrasonic measuring tools may be used.  Industrial machinery installation, repair and maintenance workers also work with hand and power tools, such as cutting torches, welding machines and soldering guns.  Some of these workers use metalworking equipment, such as lathes or grinders, to modify parts to specifications.  Maintenance mechanics must be able to detect and diagnose minor problems and correct them before they become major ones.  For example, after hearing a vibration from a machine, the mechanic must decide whether it is due to worn belts, weak motor bearings or some other problem.  Computerized maintenance, vibration analysis techniques and self-diagnostic systems are making this task easier.  Self-diagnostic features on new industrial machinery can determine the cause of a malfunction and, in some cases, alert the mechanic to potential trouble spots before symptoms develop.  After diagnosing the problem, the mechanic disassembles the equipment and repairs or replaces the necessary parts.  Once the machine is reassembled, the final step is to test it to ensure that it is running smoothly.  When repairing electronically controlled machinery, maintenance mechanics may work closely with electronic repairers or electricians who maintain the machine’s electronic parts.  However, industrial machinery installation, repair and maintenance workers increasingly need electronic and computer skills to repair sophisticated equipment on their own.  

Although repairing machines is the most important job of industrial machinery installation, repair and maintenance workers, they also perform preventive maintenance.  This includes keeping machines and their parts well oiled, greased and cleaned.  Repairers regularly inspect machinery and check performance.  For example, they adjust and calibrate automated manufacturing equipment such as industrial robots and rebuild components of other industrial machinery.  By keeping complete and up-to-date records, mechanics try to anticipate trouble and service the equipment before factory production is interrupted.  A wide range of tools may be used when performing repairs or preventive maintenance.  Repairers may use a screwdriver or a wrench to adjust a motor, or a hoist to lift a printing press off the ground. When replacements for broken or defective parts are not readily available, or when a machine must be quickly returned to production, repairers may sketch a part that can be fabricated by the plant’s machine shop.  Repairers use catalogs to order replacement parts and follow blueprints and engineering specifications to maintain and fix equipment. 

Installation of new machinery is another responsibility of industrial machinery installation, repair and maintenance workers.  As plants retool and invest in new equipment, they increasingly rely on these workers to properly situate and install the machinery.  As employers increasingly seek workers who have a variety of skills, industrial machinery installation, repair and maintenance workers are taking on new responsibilities.

Operating Engineers                                                                    Back to top

Nature of the Work:

Construction equipment operators use machinery to move construction materials, earth and other heavy materials and apply asphalt and concrete to roads and other structures.  Operators control equipment by moving levers or foot pedals, operating switches or turning dials.  The operation of much of this equipment is becoming more complex as a result of computerized controls.  Construction equipment operators may also set up and inspect equipment, make adjustments and perform minor repairs.  Construction equipment operators include operating engineers and other construction equipment operators, paving, surfacing and tamping equipment operators and pile driver operators.  Operating engineers and other construction equipment operators, operate 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 and load it into trucks or onto conveyors.  In addition to the familiar bulldozers, they operate trench excavators, road graders and similar equipment.  Sometimes, they may drive and control industrial trucks or tractors equipped with a forklift or boom for lifting materials, or hitches for pulling trailers.  They also may operate and maintain air compressors, pumps and other power equipment at construction sites.  Construction equipment operators who are classified as operating engineers have the capability of operating several different types of construction equipment. 

Paving and surfacing equipment operators use levers and other controls to operate machines that spread and level asphalt or spread and smooth concrete for roadways or other structures.  Asphalt paving machine operators turn valves to regulate the temperature and flow of asphalt onto the roadbed.  They must take care that the machine distributes the paving material evenly and without voids and make sure that there is a constant flow of asphalt going into the hopper.  Concrete paving machine operators move levers and turn hand wheels to lower an attachment that spreads, vibrates and levels wet concrete within forms.  They must observe the surface of the concrete within forms.  They must observe the surface of the concrete to identify low spots where workers must add concrete.  They use other attachments to the machine to smooth the surface of the concrete, spray on a curing compound and cut expansion joints. 

Tamping equipment operators operate tamping machines that compact earth and other fill materials for roadbeds.  They may also operate machines with interchangeable hammers to cut or break up old pavement and drive guardrail posts into the earth. 

Pile driver operators operate pile drivers, large machines mounted on skids, barges or cranes, which hammer piles into the ground.  Piles are long heavy beams of wood or steel that are driven into the ground to support retaining walls, bulkheads, bridges, piers or building foundations.  Some pile driver operators work on offshore oil rigs.  Pile driver operators move hand and foot levers and turn valves to activate, position and control the pile-driving equipment.

Painters and Paperhangers                                                           Back to top

Nature of the Work:

Paint and wall coverings make surfaces clean, attractive and bright.  In addition, paints and other sealers protect outside walls from wear caused by exposure to the weather.  Although some people do both painting and paperhanging, each requires different skills.  Painters apply paint, stain, varnish and other finishes to buildings and other structures.  They choose the right paint or finish for the surface to be covered, taking into account durability, ease of handling, method of application and customers’ wishes.  Painters first prepare the surfaces to be covered, so that the paint will adhere properly.  This may require removing the old coat of paint by stripping, sanding, wire brushing, burning or water abrasive blasting.  Painters also wash walls and trim to remove dirt and grease, fill nail holes and cracks, sandpaper rough spots and brush off dust.  On new surfaces, they apply a primer or sealer to prepare the surface for the finish coat.  Painters also mix paints and match colors, relying on knowledge of paint composition and color harmony.  In large paint shops or hardware stores, these functions are automated.  There are several ways to apply paint and similar coverings.  Painters must be able to choose the right paint applicator for each job, depending on the surface to be covered, the characteristics of the finish and other factors.  Some jobs need only a good bristle brush with a soft, tapered edge; others require a dip or fountain pressure roller; still others can best be done using a paint sprayer.  Many jobs need several types of applicators.  The right tools for each job not only expedite the painter’s work but also produce the most attractive surface.  When working on tall buildings, painters erect scaffolding, including “swing stages,” scaffolds suspended by ropes or cables attached to roof hooks.  When painting steeples and other conical structures, they use a bosun’s chair, a swing-like device. 

Paperhangers cover walls and ceilings with decorative wall coverings made of paper, vinyl or fabric.  They first prepare the surface to be covered by applying “sizing,” which seals the surface and makes the covering stick better.  When redecorating, they may first remove the old covering by soaking, steaming or applying solvents.