CH 7. Means of Egress

In buildings that don't require panic hardware on exit doors, the model building codes define the types of door locks that may be installed: — exit doors can feature deadbolt locks that operate with the action of the latch and do not require keys, special tools, or knowledge to operate. — Thumb-turn bolts that operate independently of the door latch are examples of unacceptable locking devices on the egress (inside) side of exit doors

Bolt locks

Common exit in high rise building/ hospitals as a means of passing through a fire-barrier wall separating two fire compartments. May substitute for other exits if they dont compose 50% of the total exit capacity of the building. 2 types -egress one building to area of refuge in another building on same level -Egress through fire barrier/wall to an area of refuge at approx same level in Bldg. for protection.

Horizontal Exits

These exits req. fire walls or fire-barrier walls w/ at least 2 hr fire- resistance rating. A 1 1/2 hour fire rated door assembly installed in the fire barrier to permit movement between the two compartments. *doors swing in the direction of the exit travel. Wall=2hr FR. DOOR= 1. 1/2 for

Horizontal exits

Occupant load is BEST described as the:

total number of persons for which the means of egress of a building or portion thereof is designed.

Panic Hardware

Locking hardware that may be required based upon occupancy classification and occupant load. Occupants should be able to operate ________ hardware as follows: — Causing the latch to release by applying a force of no more than 15 pounds (7.5 N). — Setting the door in motion by applying a force of no more than 30 pounds (15 N) (Figure 7.13). In some occupancies, operating panic hardware to open exit doors activates an alarm. This alarm is intended to notify the employees or management or to help prevent theft.

When occupant loads are greater than 500, the codes generally require how many separate exits?

Minimum of 3

Who verifies that doors, stairs, and walls conform to the adopted building and safety codes.

The inspector, inspectors will also; -Recognize and evaluate those building components that serve as compo- nents of a means of egress. -Be aware of any exemptions in the means of egress requirements that are permitted in structures that are protected by automatic sprinkler systems. NFPA® 101, Life Safety Code®, contains specific examples of automatic sprinkler exemptions.

Electromagnetically locked.

This type of hardware may be used on doors in the means of egress that are not otherwise required to have panic hardware. These doors must have listed hardware that incorporates a built-in switch. This switch must directly supply power to the electromagnetic lock, not through a computer system or other device as would be used in access-controlled egress systems. This hardware is a basic system that de- tects a push on the hardware and supplies power to the mag-lock in the doorframe (Figure 7.16). Card readers or punched-in codes are not needed to gain access. System requirements: — Listed hardware that is affixed to the door and has an obvious method of operation. — Must be capable of being operated with one hand. — Operation of the hardware releases to the electromagnetic lock and im- mediately unlocks the door. — Loss of power to the hardware automatically unlocks the door.

Inspectors are concerned about floor coverings because:

of the flammability of the materials used.

Fire-resistant-rated walls are used to

separate designated exits from other parts of the building. The fire-resistance rating is based on the type of occupancy, building height, type of building construction, and whether the building has an automatic sprinkler system

The capacity of the means of egress is BEST described as:

the number of people who can move along the means of egress.

Within each model code, maximum travel distances vary depending on the type of occupancy and:

whether the building has an automatic sprinkler system.

Which of the following can slow access by fire and emergency services personnel and has been responsible for many fatalities?

Security Bars

How are exit doors required to open?

Towards the direction of exit travel. Each door opening must be wide enough to accommodate the number of people expected to travel through the door in an emergency.

Two life safety functions of doors

-separate occupants from fire and products of combustion -serve as means of egress system

This type of hardware is designed to allow oc- cupants to egress freely while enabling the door to be secured from the outside (Figure 7.15). The occupant must use a security card or enter a code to gain entrance. Several things are required for this type of hardware: A sensor on the egress side detects an occupant ap- proaching. — Loss of power to the hardware automatically unlocks the doors. — The doors must be arranged to unlock from a manual unlocking device that delays relocking for a mini- mum of 30 seconds and has a sign stating, "PUSH TO EXIT." — Activation of the building fire alarm, fire detection, or automatic sprinkler system will unlock the doors. — Some entrance doors in certain occupancy classes may not be allowed to be secured during periods of occupancies - or at all.

Access-controlled egress

Which of the following are likely to be poorly maintained and not secured to the wall?

Fire Escape

In new buildings, model codes require that swinging or hinged doors be a minimum of ________ clear and unobstructed width?

In new buildings, model codes require that swinging or hinged doors serving as a component of a means of egress provide a minimum of 32 inches (800 mm) of clear unobstructed width (Figure 7.11, p. 252). Exceptions under building code.

Who typically calculates the proposed occupant load?

Design professional

Delayed egress.

Doors unlock upon operation of automatic sprinkler system or automatic fire detection system. Doors also unlock when power controlling the locking mechanism is lost. Additional requirements: —Initiating the release mechanism by applying a force of no more than 15 lbs (67 N) must permit the door to open within 15 seconds, or in some cases, 30 seconds. — Opening the door will activate an audible signal. — Doors must be labeled with a sign stating, "PUSH UNTIL ALARM SOUNDS. DOOR CAN BE REOPENED IN 15/30 SECONDS." — Occupants must not have to pass through more than one door equipped with delayed egress before reach- ing an exit.

Which of the following is the BEST reason why exits should be located remotely from each other?

Helps minimize travel distance to an exit

Smoke proof enclosures

Highest level of protection from smoke, heat, and toxic gases in a stairway. 2 ways to smoke proof is -pressurize it - natural/mechanical ventilation

Exit Discharge

Is that portion of means of egress that is between the exit and a public way.