Chapter 3 Set 03: Fire-Resistant Doors, Windows, and Fire-Protection Openings: Types, Construction

How are doors generally classified?

By how they operate: swinging, sliding, folding, vertical, and revolving.

Why is door construction important to firefighters?

It affects the door's ability to limit fire and flow paths and the difficulty of forcing entry.

What materials are commonly used to make doors?

Wood, metal, and glass, sometimes with hardboard, fiberglass, or plastic veneers.

How does a swinging door operate?

It rotates on hinges attached to a side jamb or on pivot posts supported at the top and bottom.

What is the difference between single-acting and double-acting swinging doors?

Single-acting doors swing one direction; double-acting doors swing in both directions.

What type of door is generally identified for required exit doors?

Swinging doors, although other types may be allowed under specified conditions.

How does the chapter describe sliding-door operation?

Rollers move the door along a track, with guides preventing lateral swinging.

What are the three sliding-door configurations described?

Surface sliding, pocket sliding, and bypass sliding.

What is a pocket door?

A pocket door slides into a wall.

What space-saving advantage do sliding doors offer?

Sliding doors avoid the floor space needed for a swinging door.

Where are sliding doors commonly used?

Elevators, storefronts, residences, and some fire-protected openings.

What egress concern does the chapter emphasize regarding sliding doors?

Sliding operation can slow passage through an exit.

How does a folding door operate?

It hangs from a track with rollers or glides and folds in bifold or multifold sections.

Where are folding doors used?

Homes and room-dividing partitions.

What special condition applies to egress fire-door assemblies?

Assemblies used for required egress must be specifically tested and listed for that use.

What is a vertical or overhead door?

A door opening in a vertical plane, used at loading docks, garages, freight elevators, and some fire-protected openings.

What construction forms can vertical doors take?

A single rising leaf, multiple horizontal panels, or interlocking metal slats that roll up.

What helps overcome the weight of a vertical door?

Counterweights or springs.

How may a vertical door be operated?

It may be raised manually, by chain hoist, or by a powered mechanism.

How is a revolving door constructed?

Three or four wings rotate within a circular frame.

What is the energy-saving purpose of a revolving door?

It limits airflow and heating or cooling losses.

What problems can revolving doors cause during a fire?

They slow evacuation and can prevent hose or equipment movement into the building.

How can many revolving doors provide a larger emergency opening?

Their wings collapse under pressure into a book-fold position.

What mechanisms hold revolving-door wings in position?

Older models use chain keepers or stretcher bars; newer models may use spring-loaded cam-in-groove hardware.

How is a wood panel door constructed?

Vertical and horizontal members frame openings filled with thin wood panels, glass, or louvers.

What is a flush or slab door?

A door with flat full-height face panels over a solid or hollow core.

What forms a solid-core door?

Laminated wood blocks, particleboard, or mineral composition beneath surface layers.

How may an exterior solid-core door be reinforced?

An exterior sheet-metal layer may improve security and hinder forcible entry.

How is a hollow-core door constructed?

Thin face panels surround grid or honeycomb spacers of wood, plastic, or fiberboard.

Where is a hollow-core door generally used?

It is commonly an interior door with little insulation value.

How does a solid-core door compare with panel and hollow-core doors as a fire barrier?

It is generally a better barrier, even without a fire-door rating, provided it is closed.

How do framed and frameless glass doors differ?

Framed doors have glass within a wood or metal frame; frameless doors attach hardware directly to the glass sheet.

Where are glass doors most common?

Office and mercantile buildings.

What glazing does the chapter describe for glass doors?

Tempered glass and security plastics such as Lexan or Plexiglas.

What thickness does the chapter describe for a typical hollow metal door?

About 1-3/4 inches overall, with smooth sheet-metal faces about 1/20 inch thick.

How are steel and aluminum flush-door interiors commonly supported?

Steel doors use vertical ribs about 6-8 inches apart; aluminum doors commonly use hardboard and honeycomb-patterned paper cores.

How may a heavy corrugated-steel door be constructed?

A steel frame supports one or two corrugated sheets.

What is the purpose of a fire door?

Protect an opening in a fire-rated wall and limit fire spread within a building.

How do fire doors differ from ordinary doors?

Their construction, hardware, protection rating, and required closing operation are designed for fire protection.

What determines the design and operation of a fire door?

The occupancy, available space around the opening, and required fire-protection rating.

What special openings may have fire doors?

Elevators, security openings, chutes, service counters, and dumbwaiters.

What hazards can automatic fire-door closure create for firefighters?

Doors may trap crews or pinch hose, interrupting water flow while leaving a gap in the fire barrier.

Why should fire-door locations be included in preincident information?

Some doors are heavy or difficult to reopen after closure, and crews may be unable to control them during a fire.

Where are overhead rolling steel fire doors commonly used?

In various fire-protected openings.

What space advantage do overhead rolling fire doors have?

They do not need wall space beside the opening.

What is a limitation of overhead rolling fire doors regarding egress?

They are excluded from required means-of-egress openings.

How does an overhead rolling steel fire door normally close?

A fusible link releases it to close by gravity.

What components are used in overhead rolling steel fire doors?

Interlocking steel slats, releasing devices, counterbalance mechanisms, governors, and wall guides.

How do horizontal sliding fire doors commonly close?

A fusible link releases the door, which moves along a track by gravity or a counterweight.

Where are horizontal sliding fire doors commonly found?

Older industrial buildings.

What is a limitation of horizontal sliding fire doors regarding egress?

They are not used across required means-of-egress openings.

How does a metal-covered wood-core fire door resist heat?

The wood core insulates and metal shields it from fire.

Why does a metal-covered wood-core fire door have a vent hole?

To release gases from heated wood decomposition.

What is a tin-clad fire door?

A door clad with terneplate, described as a tin-and-lead material.

Where are swinging fire doors commonly used?

Stairwell enclosures and corridors.

What must remain clear for swinging fire doors?

Their swing path.

What condition is necessary for a swinging fire door to perform its protective function?

It must be closed during the fire.

What is the difference between automatic-closing and self-closing fire doors?

Automatic doors are held open and close when activated; self-closing doors remain closed and return closed after being opened.

How does a fusible link activate a fire door?

It melts in heat and releases the door.

What is a limitation of fusible links in fire doors?

They react more slowly than smoke or rate-of-temperature-rise detection.

What advantages do smoke-detector-operated fire doors have?

They close sooner and are easy to test.

What maintenance needs do smoke-detector-operated fire doors have?

Detectors cost more, need cleaning, and must be positioned correctly.

Can a fire door be released by the building's fire alarm system?

Yes, some close when a component of the fire alarm system activates.

What functions do windows provide for occupants and firefighters?

Light, ventilation, access, escape, and rescue.

Why can modern nonoperable windows complicate firefighting?

They reduce options for tactical ventilation and fire-suppression team access.

What are the main parts of a window unit?

A frame, one or more sashes, glazing, and operating or securing hardware.

What is a window frame?

The perimeter fixed to the surrounding wall.

What are the main members of a window frame?

The sill, side jambs, and head jamb.

What is a window sash?

A fixed or movable framed unit within the window frame that holds the glazing.

What is a windowsill?

The lowest horizontal frame member, supporting the sash and hardware.

What is glazing?

The glass in a window.

How do single-, double-, and triple-glazed windows differ?

They indicate one, two, or three glass layers, with spaces between multiple layers.

What are the two broad classifications of windows?

Fixed or nonoperable, and movable or operable.

What is a fixed window?

A stationary glazed sash in a frame.

Where are fixed windows commonly found?

Storefronts, high-rise offices, around doors, in skylights, and in residences.

How does a double-hung window operate?

Two sashes slide vertically past one another.

How does a single-hung window differ from a double-hung window?

Only one sash opens.

What holds the movable sashes of hung windows in position?

Counterweights, springs, or spring-loaded mechanisms.

How does a casement window operate?

Its side-hinged sash usually swings outward.

How does a horizontal sliding window operate?

At least one of two or more sashes moves horizontally.

How do awning and hopper windows differ?

Awning windows are hinged at the top and swing outward; hopper windows are hinged at the bottom.

What is an advantage of awning windows?

They can provide ventilation while remaining open during rain.

What is a jalousie window?

Many narrow overlapping glass sections operated together to swing outward.

What ventilation advantage do jalousie windows provide?

The opening can be adjusted while limiting entry of rain.

How does a projecting window operate?

It swings outward at the top or bottom while sliding in grooves.

How does a pivoting window operate?

The sash rotates horizontally or vertically around a central axis.

What are common window security arrangements?

Metal bars or screens attached to the frame.

Why are window security bars hazardous during a fire?

They can trap occupants or firefighters and delay access.

What does the chapter direct regarding security bars when interior operations begin?

Remove or disable them as needed for a rapid emergency exit.

What is the purpose of rolling steel shutters?

They protect window openings in fire separations.

How do rolling steel shutters usually operate?

They usually close by gravity when a fusible link melts.