Fire aisles.

TM 38-400/NAVSUP PUB 572/AFMAN 23-210 MCO 4450.14/DLAM 4145.12

-- DISCUSS the fire aisle regulations with the group and

-- "The location, number, length, and width of these

be sure each member has a clear under standing of

aisles depend upon certain conditions."

them.

-- "WHAT ARE THE DETERMINING FACTORS?"

-- CAUTION-- BE SURE YOU, AS LEADER, UN

OBTAIN the following points from the group and then

DERSTAND THEM.

have them designate where they would place main

-- "What factors usually determine the location and

aisles on the sample layout under varying conditions:

number of fire aisles?"

FIRE DOORS

TYPE OF STORAGE

(mechanically or by hand)

SUBSTANDARD WALLS

SIZE OF EQUIPMENT

WINDOWS

LOCATION OF DOORS

LOCATION OF FIRE FIGHTING

SIZE OF LOTS

EQUIPMENT

MATERIAL SUBJECT TO SPONTANEOUS

COMBUSTION

-- Have the group explain WHERE and WHY main

aisles are located in their own respective areas of

operation.

-- "What is the MAXIMUM WIDTH of FIRE AISLES?"

-- Have the group designate where they would

(1) These serve as the lifeline or arteries of a

place fire aisles on a sample plan.

warehouse. There should be no "breaks" or "bottle

necks" and they should be kept clear at all times. THEY

(1) Fire fighting aisles were once widely used

SHOULD BE LOCATED so that they give direct access

in warehouses. Experience has proved that they are

to shipping and receiving platforms, doorways between

often of little help in controlling fire and may actually

sections, and, in multistory buildings, give access to

constitute a fire hazard. The present thinking is that fire

elevators and conveyors. Although 10 feet is the

aisles should be eliminated except along substandard

normally accepted width in warehouses utilizing 4,000-

interior walls and where they lead to fire fighting

pound forklift trucks, the WIDTH may vary. Size is

equipment. Ordinarily, fire is on the surface of the

determined by the type of mechanical equipment used.

material; the greater the surface, the greater the fire

Aisles should be wide enough to permit equipment to

hazard. The exception to this is material subject to

pass and to permit easy working of the forklift truck.

spontaneous ignition; which must be watched constantly

Experience has taught us that a forklift truck of 2,000

for over heating; however, fire aisles will not prevent

pound capacity requires a 7-foot aisle, and a truck of

ignition.

6,000 pounds requires an 11-foot by 6-inch aisle in

(2) In every depot or storage activity a certain

which to work efficiently.

number of fire aisles are necessary. The policy in each

(2) The NUMBER of transportation aisles in a

should be the guide in establishing these aisles.

section or on a floor of a multistory building depends on

ALTHOUGH THEY ARE NECESSARY, THEY SHOULD

the number of communicating doors and elevators that

BE REDUCED TO A MINIMUM IN NUMBER AND

must be used to move material in and out of the area.

WIDTH.

THEY WASTE VAL UABLE STORAGE

The number is also deter mined somewhat by the size

SPACE. It is seldom necessary to have fire aisles wider

of the lots and the number of different commodities. In

than 24 inches. In many cases, fire aisles can be

a section where ONE ITEM will fill the entire area, the

eliminated by a simple change in the location of the fire

section could be stacked to its capacity. It would be

fighting apparatus. Previously, it has been mentioned

necessary to leave only enough space to "get at" the

that extinguishers and hose fixtures should never be

items and to permit access for fire prevention or fire

hung BEHIND posts or columns opposite the aisle. Fire

fighting purpose.

aisles must be used adjacent to windows THAT WILL

BE USED AS ENTRANCES by firemen. Fire aisles are

d. Fire aisles.

not necessary next to exterior walls or standard walls

-- "FIRE AISLES are NECESSARY IN SOME LO

which serve as dividers of sections or units of a

CATIONS under FIRE REGULATIONS."

warehouse.

-- "What are the REGULATIONS governing our own

(3) Standard firewalls separating buildings or

installation?"

dividing warehouses and sheds into fire areas are

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