Chapter 7

Question 1

BLEVE:
The DOT Emergency Response Guidebook (ERG 2008) recommends pulling back __ mile in these instances.

Answer 1

1/2

Question 2

Some industrial heaters or boilers use steam or air atomizers, but most residential units use mechanical atomizers. Considering that the oil pressure required for maximum efficiency ranges from __ psi, any of these systems may be dangerous to firefighters who are unfamiliar with them.

Answer 2

600 to 1,000

Question 3

Gas Leak Without Fire:

The DOT ERG 2008 recommends staging anywhere from __ feet from the source of both LPG and natural gas leaks.

Answer 3

160 to 330

Question 4

Since the LEL for natural gas is __, many fire departments establish the perimeter at 10 percent of that figure — 0.5 percent (5,000 ppm).

Answer 4

5 percent (50,000 ppm)

Question 5

A common error is to establish a perimeter that is too small. As described in Essentials, the recommended isolation distance is that equal to __ full span between the adjacent poles or towers in all directions from a break in a wire or the point of contact with the ground.

Answer 5

one

Question 6

Alternating current detectors:

Under ideal conditions, these devices may be able to detect AC current in a single 120-volt line from as far as __ feet. However, if the conductor is lying on wet soil, the range may be reduced to as little as __ foot. With higher potentials, such as those in distribution and transmission lines, the detection range can increase to more than __ feet.

Answer 6

15

1

500

Question 7

When power from the normal utility source fails, some emergency generators may start automatically. If these units are not disconnected from the system, the power lines can be reenergized with __ volts from the generators.

Answer 7

240

Question 8

If extinguishing a fire on an upper floor of a 50- × 100-foot building results in 6 inches of water accumulating on the floor, the total weight of that water exceeds __ tons.
Page 195

Answer 8

75

Question 9

Because the lower explosive limit for propane is __, any reading above 0.15 percent (1500 ppm) may be too dangerous, and it may be advisable to locate control points where readings indicate a lower concentration.

Answer 9

1.5% (15,000 ppm)

Question 10

Because the lower explosive limit for propane is 1.5% (15,000 ppm), any reading above __ percent (1500 ppm) may be too dangerous, and it may be advisable to locate control points where readings indicate a lower concentration.

Answer 10

0.15

Question 11

Since the LEL for natural gas is 5 percent (50,000 ppm), many fire departments establish the perimeter at __ percent of that figure — 0.5 percent (5,000 ppm).

Answer 11

10