Materials Exam 3

What is commonly used to finish interior walls and ceiling surfaces of buildings?

Plaster and gypsum board

Plaster is composed of ? or ? with water, sand, and sometimes glass or hair fibers.

Gypsum or lime

Plaster was used until the development of what in the early twentieth century?

Gypsum

When exposed to flame, a plaster finish releases what that slows the fire’s spread?

Water vapor

Plaster contains what properties that will slow heat flow from a fire?

Insulating properties

What kind of plaster consists of multiple layers of integrally colored, polished plaster?

Venetian

What kind of plaster is often used for a high-quality finish over gypsum board?

Veneer

Gypsum is ?, a widespread, common, white or gray, soft mineral.

Hydrated calcium sulfate

Gypsum is made of what gypsum plus sand, water, and additives to control setting?

Calcined

What kind of plaster is coarse, contains cement, and forms hard surfaces?

Stucco

Which part of the gypsum process is environmentally damaging?

Mining

What can irritate the eyes and respiratory system?

Plaster dust

From the 1940s-1980s, what were added to acoustical plaster ceiling tiles and wall and ceiling finishes?

Asbestos fibers

What is applied to walls in several layers to produce a smooth surface that takes finishes very well?

Plaster

What is applied as a thin coating to gypsum wallboard or to existing surfaces to improve the finish?

Veneer plaster

What was traditionally either made at the site or cast in molds in a workshop?

Ornamental plasterwork

Gypsum plaster with metal lath can achieve ? or ? ratings and can be used to make what for steel columns and beams?

1-hour or 2-hour ratings, fire-rated enclosures

Steel or wood-framed veneer plaster partitions can achieve a what rating?

1-hour

Decorative plaster finishes should meet test requirements for ?, ?, and ? with samples submitted illustrating finish color and texture.

Pencil hardness, scrub resistance, and chemical exposure

Gypsum plaster is applied over a ? typically supported by gypsum or ? or directly onto masonry or concrete.

Base coat, metal lath

What kind of plaster is applied as a basecoat followed by a finish coat?

Two-coat plaster

What kind of plaster is applied first as a scratch coat followed by a brown coat and finally a finish coat?

Three-coat plaster

What is any plaster coat that is applied before the finish coat called?

Base coat

What must adhere firmly to the metal lath and provide a bond for the second or brown coat? 

Scratch coat

Several coarse ? with perlite and sometimes Portland cement added are applied to accommodate ? and ?

Brown coats, expansion, contraction

The what serves as either the finished surface or as a base coat for another material?

Finish coat

Label

Framing or furring

Metal lath

Scratch coat

Brown coat

Finish coat

What kind of material made from expanded metal is used with three-coat plaster? 

Metal lath

Plaster can be applied directly to ?, ?, or ? where the surface is rough and porous enough to produce a good bond.

Brick, clay tile, or concrete masonry

Wood or metal ? can be applied vertically or horizontally to hold lath or other finish materials onto hard surface, or to provide airspace between the wall and finish materials.

Furring

What purpose is resilient furring channels that allow the plaster to move independently of the masonry for? 

Acoustic purposes

How many days is the curing process?

2 days

Partitions merely 2’’ thick can be made by applying what to both sides of metal lath on 3/4’’ channel studs?

Three-coat plaster

What kind of issues is plaster susceptible to that are caused by water infiltration, structural movement, and vibration? 

Crack, loosen, or sag

Falling plaster is caused by what?

Problems with its substrate

What is the generic name for sheet materials with a noncombustible gypsum core that is covered with a paper surface? 

Gypsum board

Gypsum board has a high level of ? with low flame spread and low smoke development?

Fire resistance

Gypsum wallboard is made by mixing stucco with dry additives such as ?, ?, ?, or ?

Perlite, starch, fiberglass, or vermiculite

Gypsum has the potential to produce what in a landfill?

Toxic hydrogen sulfide

Gypsum board is often applied to ? or ? studs with ? in the voids.

Metal, wood, acoustical insulation

What sheet sizes are available for gypsum board? 

1/4'' to 1'' thick from 2-8 ft to 4-20 ft

What does GFRG stand for?

Glass fiber reinforced gypsum

GFRG can be produced in thin, high-strength shapes that are inherently what?

Flame-resistant

GFRG is not appropriate for damp conditions of where temperatures regularly rise to above?

122 F

GFRG boards have a ? reinforced gypsum core and a ? immediately below the gypsum faces.

Glass fiber, glass fiber tissue

1/2'' gypsum board

1'' gypsum board

Wall base

Metal base anchor

Metals used in buildings include pure elements such as:

Lead, iron, copper, tin, zinc

Two or more metals are more commonly combined into what?

Alloys

What is the ability of a metal to be drawn out into a long, thin form such as a wire?

Ductility

What metals can be shaped or formed without cracking or rupturing?

Malleable

Rust on iron is an oxide that is produced by:

Corrosion

What is a brown to greenish film that is formed on the surface of bronze and copper by oxidation of the metal’s surface? 

Patina

Metals are classified as what two types? 

Ferrous and nonferrous

What is the principal element in ferrous metals? 

Iron

Metallic iron is extracted from:

Iron ores

What addition will increase the metal strength and hardness but also reduce the ductility and its ability to bewelded? 

Carbon

Iron is produced as:

Cast iron, wrought iron, and steel

Which kind of iron is cast into ornate designs and used for waste plumbing in buildings?

Cast iron

Which kind of steel is generally any unalloyed steel with limited amounts of residual carbon or other elements?

Carbon steel

The ? and processing of metals creates significant environmental impacts, including erosion, the formation of sinkholes, the contamination of groundwater, and the loss of biodiversity.

Mining

What is the extraction of metal from ore by heating and melting? 

Smelting

To make steel, molten ? with at least 25% recycled scrap steel added is put into a steel converter where excess carbon is burned away.

Pig iron

? a ferrous metal with zinc greatly improves its corrosion resistance.

Galvanizing

Nonferrous metals contain little or no what?

Iron

Many metals are good conductors of electricity; ? is used to conduct electricity in buildings. 

Copper wiring

Which is the most abundant metal in earth’s crust? 

Aluminum

Which coatings make aluminum more durable? 

Zinc

What is used in heat-resistant paint and for pigments?

Powdered aluminum

Which metal if left unfinished will turn brown and develop a green patina? 

Copper

Which metal, if added to copper will produce bronze? 

Zinc

Which metal is necessary to human health and is generally safe for contact with food? 

Copper

Copper and its alloys have what properties?

Antimicrobial

Which type of chromium is toxic and its production is regulated?  

Hexavalent chromium

Various compounds of what are used to make colored pigments and dyes?

Chromium

What is usually extracted from ore by smelting or chemical leaching?

Silver

What is the application of gold leaf or powder to a solid surface to produce a thin decorative coating? 

Gilding

What is done to bathroom faucets to improve appearance and resistance to corrosion and wear? 

Electroplating

Which metal is used in the production of float glass? 

Tin

Which metal was used in the aerospace industry in the 1950s and is used today as a building material? 

Titanium

 The term synthetic denotes materials made with ______________________ as opposed to natural materials.

Human intervention

What are made with significant amounts of renewable plant materials such as cellulose and starch?

Bioplastics

 Most synthetic materials are based on the carbon atom and are derived from ________________________ made from petroleum or natural gas. 

Petrochemicals

 Plastics are poor electrical conductors and exhibit a high level of ______________________________.

Thermal expansion

 Synthetic plastics are made of synthetic resins in combination with ___________________,_______________________, _______________________, ______________________ and other materials. 

Fillers, stabilizers, plasticizers, pigments

Which synthetic resin adds properties such as durability or heat resistance?

Fillers

Which synthetic resin increases resistance to ultraviolet rays, oxygen, and other environmental chemicals?

Stabilizers

Which synthetic resin increases flexibility, resiliency, and impact resistance? 

Plasticizers

 All synthetic plastics are ___________________ and most emit noxious fumes in fires.

Combustible

What was developed from cellulose to imitate silk fiber in 1981?

Rayon

 According to the EPA Toxic Substances Control Act Chemical Substance Inventory, there are over ________________ chemical substances listed with the EPA as manufactured in the U.S. 

84,000

 Synthetic materials can last for hundreds of years and pollute both the _________ and the________________________________. 

Land, marine environment

One major VOC irritant is ___________________________, a colorless, strong-smelling gas used in themanufacture of synthetic resins and dyes, and as s preservative and disinfectant. 

Formaldehyde

Evidence indicates that _______________ may possess liver toxicity, thyroid toxicity, and neurodevelopmentaltoxicity. 

PBDEs

 Plastics are categorized as two basic types _____________________ and ________________________.

Thermoplastic and thermoset

 Which type of plastic becomes soft when heated and can be remolded repeatedly?

Thermoplastics

 Which type of plastic is permanently hardened and cannot be softened and remolded?

Thermoset

 Nylon, acrylics, polyesters, vinyls, are considered which type of plastic? 

Thermoplastics

What are very clear, hard, lightweight thermoplastics?

Acrylics

Which plastic is resistant to chemicals, UV light, impact and abrasion? 

Nylon

What are combustible at high temperatures, but tend to shrink away from flames and self-extinguish?

Polyesters