BOOK 29 Flashcards
Lamella Arches are common where?
Common on gymnasiums, large buildings used for recreational actives, large supermarkets
Natural gas has an ignition temperature of _____ degrees F, and has a flammable range between ___ and ___ percent.
1,100 degrees F; 4 and 14 percent
TRUE OR FALSE: During positive pressure operations, do not “open the structure up” as is common practice.
TRUE
A facade can be defined as an ____________________________.
An identifiable style of construction on the exterior of a building that will conceal and spread the travel (extension) of fire
Roof ventilation operations on a corrugated metal building should be ______________.
Should be considered extremely dangerous
Although Lamella Arch roofs offer some protection when exposed to fire, total roof collapse may occur if fire removes more than ___% of the roof structure. Total roof collapse of the roof can result from “________________”
20%; the domino effect
Cable elevators are either _____ or _____ type.
Either drum or traction type
Is a Louver off a Main an Offensive or Defensive cut?
Defensive
Lam beams may be bolted together to provide lengths well in excess of ______.
100 feet
Compound Meters are used to calculate water usage for domestic water services that can use low and high water flows. Compound meters are ______ or larger and are normally found directly adjacent to shut-off valves
4 inches or larger
The equipment room for hydraulic elevator is normally located _______________, but can be at any floor level or ____ to ____ feet away from the elevator shaft.
Normally located at the lower level of a building; 50 to 100 feet away from the elevator shaft
When is a Figure 8 Bend used?
A Figure 8 Bend is used to tie 2 ropes of the same size together
Industrial shut-off valves, known as __________ valves, are used for high pressure applications.
Nordstrom valves. They are larger than standard shut-off valves, and may require more effect and larger tools to shut off the flow of gas
A Lamella Arch is supported by ____________ or _____________.
Supported by exterior buttresses or interval tie rods with turnbuckles.
A lightweight constructed gable truss utilizes ___ x ___ or ___ x ___ wood trusses held together by metal gusset plate connectors.
2 x 3 or 2 x 4 inch wood trusses
What blowers are required for the Air Cushion Model 70A?
(2) 20”, 1/2 HP, 60 HZ
What is the thickness of the Air Cushion Model 70A?
8’
A winding drum type elevator consists of a car attached to __________ cables that pass around a winding drum and to a moving counterweight
One or more cables
Natural gas is reduced to a low pressure at the service meter (approximately ___ psi)
Approximately 1/3 psi
Center opening doors consist of two power operated panels that part simultaneously with a ______, ________ motion.
Brisk, noiseless motion
Unreinforced masonry buildings are required to be reinforced to comply with the Earthquake Ordinance. Modifications may include:
- Add steel bracing from parapet walls to roof structural members
- Metal straps across the width of the roof and attached to opposing walls. The straps are usually 1/3 of the length of the building back from the front and rear walls
- Remove the layers of composition and cover the sheathing with 1/2 plywood. The decking is then recovered with composition
Is the Pull Back Method an Offensive or Defensive cut?
Offensive
Domestic water and fire protection service for high rises is provided by a combination water service that consists of a ___ to ___ inch water meter for domestic water and ___ to ___ inch detector check valves for fire protection in the same vault.
4 to 10 inch; 4 to 12 inch
Smoke indicator holes should be placed along the path of access or egress every _________.
Every few yards
Freight elevators can be as large as ________ and have a carrying capacity of up to _________.
12’ x 14’; 3 tons
Each year in the United States, there is an average of ___ deaths to firefighters in the fire service. On average, ___ of these deaths are due to flashover, and the number is slowly rising each year.
100 deaths to firefighters in the fire service. On average, 85 due to flashover
A Lamella Arch is constructed from ___ x ___ inch wood framing with steel plates and bolts at junctions of framing.
2 x 12 inch
The ends rope in the two-line system should be swapped end for end ________.
Annually. The reason for this is to reduce wear on the most used part of the rope
Nailing blocks will usually be found every ______.
Every 4 feet
Because of the arched trajectory of a fire stream, what is recommended when using the portable monitor?
It is recommended that spotter be used to accurately direct the stream from the monitor
Natural gas emergencies can be divided into the three following categories:
1) Inside leaks
2) Outside leaks
3) Leaks resulting in fires
Domestic water services for single family dwellings will normally consist of a ___ to ___ inch single water meter with shut-off valve on one or both sides of a meter.
1/2 to 2 inch
A commercial occupancy with multiple occupancies (such as mini-malls), can be serviced with water for a domestic water service by a single water meter for an entire building or, by multiple, 1 to 2 inch water meters in separate vaults, which can supply each individual occupancy (referred to as a ______)
A battery
What is the key to safe and effective roof ventilation?
The key to safe and effective roof ventilation is the knowledge of rafter type and rafter direction
What is a Score Cut?
A score cut is a light cut of the roof covering, usually composition only. A score cut is used to facilitate the removal of multiple layers of roofing material (composition)
What blowers are required for the Air Cushion Model 100A?
(1) 20”, (1) 24”, 1/2 HP, 60 HZ
Metal gusset plate connectors may vary in size, thickness and depth of penetration, but the most common are ___ gauge steel plates with prongs that produce _____ penetration.
18 gauge steel plates with prongs that produce 3/8 inch penetration
A common odorant added to natural gas is a _________/_________ mix, which is used in solution of ______ per ______ cubic feet of gas.
Mercapitan/Thiophane mix; solution of one pint per million cubic feet of gas
What are the 4 basic types of doors used on elevators?
1) Swing hall doors
2) Single slide doors
3) Center opening doors
4) Two speed doors
It is not practical in most cases to remove cut plywood from a roof due to the method in which the plywood is nailed to the roof rafters. What is the best alternative?
The best alternative is to louver the plywood. Once all 4 cuts are complete, use a rubbish hook and push down on the near side and pull on the far side
For roof ventilation, a minimum of ____ ladders should be thrown to the involved structure.
A minimum of two ladders
The primary danger from collapse of URM buildings are the _____ and _____ walls of a building. The secondary danger from collapse are the _____ walls of a building
Front and rear walls; side walls
The welded eye on the brake bar rack is used for attachment and is rated at _______.
10,000 lbs
How should rope be dried?
Allow rope to drip dry out of direct sunlight
What will a 45-degree inspection hole tell you?
1) Rafter type
2) Rafter direction
3) Sheathing type
4) Thickness of roof composition
5) Can act as a smoke indicator
TRUE OR FALSE: Never store the Air Rescue Cushion while wet.
TRUE. Allow the cushion to dry, then fold and place on apparatus
Detector Check Valves are used to supply water for a closed fire protection system. Detector check valves can vary in size from ___ to ___.
2 to 10 inches
The spikes on the portable monitor must be sharp to provide resistance to sliding. Replace any spike if the tip diameter exceeds _______.
Exceeds 1/16 inch
If there is a fire under an elevator car, what should be done with that car?
That car should be brought to the lowest landing possible to reduce the spread of smoke
What is knot efficiency?
Knot efficiency is measured by the percentage of rope strength that remains after a knot is tied in the rope
What is “J” Hooking?
The removal of sheathing is enhanced by a “J” hook motion with an appropriate tool (pick head axe). The “J” hook motion brings the pulling tool under and up to the decking in a smooth, forceful motion that will separate the decking materials from the rafters. This is more efficient if the pulling tool is used near the rafters.
Metal exposed to fire or sufficient heat will expand, twist and possibly fail (steel begins to lose its strength at _____ degrees F)
1000 degrees F
Panelized roofs may be found on ______, _______ or _______ buildings.
Wood, masonry or concrete tilt up slab buildings
What is tensile strength?
Tensile strength is the rated breaking strength of rope when pulled in a straight line, with no knots, under laboratory conditions to a point where is can be expected to break
What should you use to ventilate a lightweight concrete roof?
Use a rotary saw with a diamond blade or carbide tipped wood blade to cut ventilation openings
In a tied truss arch, tie rods (usually ____ inch in diameter) with turnbuckles are used below each arch member to ensure the arches do no push the exterior walls outward.
5/8 inch in diameter
Shutoff valves can be located by finding the MSA since they are always adjacent to each other. Initially, what should you look for?
Initially, look for a “G” that is either chiseled or painted on the curb. A “G”, required by Cal-OSHA, marks the location where the service line passes beneath the curb and indicates which side of the building the MSA is located
Compared to negative pressure ventilation, positive pressure ventilation is approximately ______ as effective at removing contaminants from a building
Approximately twice as effective
After the Tehachapi Earthquake, building codes were modified to require the following retroactive correction on EXISTING buildings of masonry construction:
- A 4 to 6 inch concrete bond-beam cap to be laid on top of all lowered parapet walls along public ways and exits
- Parapet walls should not be higher than 16 inches including the bond-beam cap
- Exterior walls drilled at the roof rafter level and a steel anchor bar/rod installed every 4 feet and attached to the existing roof rafter. This modification rendered the fire cut of the roof rafter ineffective
The high strength core (Kern) can carry up to ___% of the load with the cover (Mantle) designed primarily for protection against abrasion
Can carry up to 90%
___% of all fire hydrant gate valves close in a clockwise direction.
98%
What is a Head Cut?
A head cut is a cut made through the roof decking that is made perpendicular to rafters. A head cut is used to locate rafters. This cut involves rolling rafters. A head cut must be done on roofs covered with plywood and diagonal sheathing. A head cut is usually the first cut made on a center rafter cut
Due to the presence of arch roofs that have been modified as per the Earthquake Ordinance and floor/joists rafters that have been anchored to the walls, exterior walls may suddenly collapse (during fire conditions) outward a distance _____________________.
A distance that is equal to at least the height of the wall
Is a Louver off a Purlin an Offensive or Defensive cut?
Defensive
What is the power required for the Air Cushion Model 100A?
115 V AC
TRUE OR FALSE: When moving an inoperative cable elevator, it is generally easier to move the car upward.
TRUE. It is generally easier to move the car upward because of the counterweights.
Bowstring arch roofs were a popular type of roof that was constructed during the ____, ____, and ____ on both small and large commercial type structures
1930s, 1940s and 1950s
TRUE OR FALSE: Roofs built with conventional construction will usually withstand fire for a much greater length of time than lightweight truss construction, resulting in a safer roof to operate on
TRUE
The “D” shaped carabiner is designed to carry the load along the ______ side.
Along the spine side
To turn off the flow of gas, turn the _____, crosswise, to the flow of gas; crosswise to the pipe
The tang
What is the primary goal of effective ventilation?
The primary goal of effective ventilation operations is the reduction or removal of smoke, heat, and fire gases (contaminants) from a structure or enclosed area in a timely manner
Measurements during actual overhaul operations have indicated that positive pressure can easily reduce carbon monoxide concentrations of 1000 ppm to approximately ____ ppm to ____ ppm.
130 to 220 ppm
If two blowers of unequal CFM are utilized in the series position, place the _____ blower about two feet back from the entrance opening and utilize the _____ blower behind the larger blower to cover the entrance opening with pressurized air
Larger; smaller
The strength of the rope is restored fully when placed over a turn of a pulley that is at least ____ times the diameter of the rope.
At least 4 times the diameter of the rope
________ is a common size of laminated beams.
6” x 36”
Do redwood plugs work with polyethylene pipe?
No, redwood plugs do not work with polyethylene pipe
What is the knot efficiency of a Bowline?
65%
The skim cut is used on a panelized roof when you are performing the cutting technique known as “________________”
Louver off a purlin
Removing screens on windows prior to using these openings for ventilation purposes will increase the efficiency of these openings by at least ____.
At least 50%
TRUE OR FALSE: Above ground gas lines must be made of steel and cannot be plastic.
TRUE
To ensure maximum life of all ropes, rope ends should be swapped end for end ________.
Annually
Retrofit modifications of URM buildings could include metals straps across the width of the building and _____ to _____ feet from walls. These straps are extremely hard on saws.
Three to four feet from walls
Conventional flat roofs uses wood rafters of various sizes (___ x ___ inches and larger) laid across outside walls, or outs wall to interior walls/structural supports.
2 x 6 inches and larger
How is tying off the brake bar rack done?
Wrap the rope twice over the yoke and through the brake bar rack pulling the bars together. Tie the rope off with two half-hitches in front of the brake bar rack.
What is the price of the Air Cushion Model 100A?
$8,500.00
What earthquake was in 1959?
The Tehachapi Earthquake
According to Book 29 overhaul operations are conducted for what purposes?
- Ensuring a fire is completely out
- Determining the probable fire cause
- Leaving the owner or insurance adjusters some means of determining the loss
What is the power required for the Air Cushion Model 70A?
115 V AC
TRUE OR FALSE: Sawtooth roofs are basically constructed the same today as they were during the 1930s and 1940s.
TRUE
A common size for a purlin is ___ x ___ inches.
4 x 12 inches
Unreinforced masonry buildings will share all or a portion of the following trademarks:
- Rafter tie-plates on the exterior of a building
- A bond-beam cap of concrete on top of parapet walls. May also have been added for strength over the windows and between the second floors of multi-story builidings
- Deeply recessed window frames. Window frames are “set” to the inside of the wall, thereby exposing about 8 inches of brick
- Windows must have arched or straight lintels
- The lime mortar between the bricks is white, porous, sandy, and may be easily rubbed away by a fingernail, knife, etc.
- In every fourth to seventh row of bricks, one row will have been laid “on-end.” This row of bricks is referred to as the “king row” and is for additional strength
Tending the main line is a ___-member operation.
One-member operation
The portable monitor is intended for a maximum flow of 890 gpm. What allows the LAFD to flow up to 1,000 GPM?
Task Force Tips has allowed the LAFD to flow up to 1,000 gpm with the portable monitor as long as it is attached to a loop of loaded 4” supply line
During inspection of the two-line system, who should you call if any problems exist?
USAR 88
When accessory cord is tied into prusik loops, the cord used should not be less than ____ inch, or more than ____ the diameter of the rope it is to be tied on
1/2 inch; 2/3
What are the 4 basic parts of a carabiner?
- Spine
- Hinge
- Gate
- Latch
The Air Rescue Cushion employed by the Los Angeles City Fire Department is similar to air cushions used in the movie industry. The cushion comes with ___ (___ horsepower) electric blowers.
2 (1/2 horsepower) electric blowers
The midpoint and the ends of the rope in the two-line system should be marked. What are the only approved markers for doing this?
- Carter MARKS-A-LOT
- Stanford SHARPIE
- Binney-Smith MAGIC MARKER
Other markers will weaken the fibers of the rope
The lower cell does not have a breather port; consequently, very little air is released on impact. This provides the lower cell with _____ the energy-absorbing capability of the upper cell.
Twice
Service lines carry natural gas at a medium pressure, which normally does not exceed ___ psi
60 psi
Fire hydrant gate valves may require ___ to ___ full turns to complete a shutdown.
18 to 26 full turns
Pickets to be used as anchors should be ____ feet in length, ____ inch round steel stock preferred. The pickets should be pounded ____ feet into the ground, at a ____ degree angle, away from the object.
3 feet in length, 1 inch round steel stock; 2 feet into the ground, at a 15 degree angle
When selecting a site to deploy the portable monitor, select a site that has suitable anchor points or has room to deploy a ____ diameter loop of hose.
10’ diameter loop of hose
When ropes and software are not in use, where should they be stored?
Store them in a cool dry location away from direct exposure to sunlight
To construct a lightweight concrete roof, an air-entrained mixture of sand, cement and, occasionally, pea gravel is pumped on top of the corrugated metal decking and 4 x 4 inch or 6 x 6 inch wire mesh to a thickness of ___ to ___ inches
3 to 4 inches
What is a Metal Gusset Plate Roof?
Wood trusses predominantly composed of 2 x 4s that are held together by metal gusset plate connectors
A single 18” blower is adequate for an average (_______ square feet) single family dwelling.
2,000 square feet
Where should members securer sheared off hydrants?
The sheared off hydrant should be secured in a safe location
At an angle of 35 degrees (the angle at the elevation safety stop), approximately _____ of the nozzle reaction force is acting sideways on the base
82%
Rafters on a bowstring arch are ___ x ___ or larger and covered by ___ x
___ inch sheathing (diagonal or straight) and composition roofing material.
2 x 6 or larger; 1 x 6 inch sheathing
What is the thickness of the Air Cushion Model 100A?
9’
The tie-down strap for the portable monitor is made of _____________ and is _____ in length.
Made of nylon webbing and is 8 feet in length
Sawtooth roofs are constructed with rafters of ___ x ___ inches or larger and utilizes wood and/or metal supports for bracing
2 x 8 inches or largerr
Do not rescue passengers of an inoperative elevator using forcible entry methods unless ___________________.
Unless they are in need of immediate medical attention. Forcible entry methods can be dangerous to passengers and fire service personnel, and will cause damage to an elevator
What is the price of the Air Cushion Model 70A?
$6,000.00
Limitations in the length and diameter of the winding drum restricts this type of elevator to ____-foot lifts and _____ speeds.
150-foot lifts and slow speeds
What is the length of yellow webbing?
12 feet
Blowers must be positioned so the _____ of air issued from a blower will completely cover the entrance opening.
Cone of air
On apartment buildings, skylights will be placed over ________ and ________. On commercial buildings, they will be placed over _______________
Hallways and stairwells; manufacturing areas
What is the knot efficiency of a Water Knot/Overhand Bend?
65%
Why is natural gas a common source of heat in buildings?
It is a common source of heat in buildings due to its convenience, abundance and relatively low cost
Interior partition walls may not support the truss at any point along the bottom chord. Eighteen-gauge “roof truss clips” may be found nailed to the bottom chord (every ____ to ____ trusses) and top plate of interior walls.
Every 3 to 5 trusses
After the Sylmar Earthquake of 1971, retroactive corrections were put into place that were designed to prevent exterior walls form collapsing outward by stabilizing the buildings by:
- Anchoring the walls to floor and roof system
- Strengthening roof construction (plywood, metal straps, etc.)
A size-up is a mental evaluation that assist in determining a course of action and the methods necessary to accomplish a desired goal. A size-up consists of three operations as follows:
- Analyze the situation
- Decide on a plan (strategy)
- Put the plan into operation (tactics)
Positive pressure ventilation has proven effective against winds of up to ______.
Up to 25 MPH
Side emergency exits on elevators are usually at least ________ wide and ________ high, and located so there is free access to the side exit of an adjacent car
16 inches wide and 5 feet high
In bungalow construction, “__________” 2 x 4 inch studs and rafters were commonly utilized during the construction of there structures.
“Rough cut”
When using the portable monitor, set the monitor on an even surface so that all ____ spikes contact the ground.
All 3 spikes
Bridge truss roofs are found on various types and sizes of commercial buildings primarily constructed during the _____ and _____.
Primarily constructed during the 1930s and 1940s
Beam span supports of ___-inch hollow steel pipe may be found.
4 inch hollow steel pipe. Expect weakening and/or collapse of these supports with failure of large portions of the roof under heavy fire conditions
What is the rating of a 2-1 picket system?
2,000 lbs
The chain saw operator should cut a minimum of _____ dice cuts before the puller begins removing sheathing.
Three dice cuts
What is Flashover?
Flashover is a condition where all of the contents of a room are heated to their ignition temperature. Once their ignition temperature is reached, the entire room will quickly be involved in flames
TRUE OR FALSE: Traction type elevators are used for higher lifts and greater speeds than drum type elevators and use a traction sheave instead of a winding drum
TRUE
Depending on the type of fire, concentrations of carbon monoxide within the range of _____ ppm to _____ ppm are easily obtainable during overhaul operations.
500 ppm to 1,200 ppm
Joists measuring ___ x ___ inches by eight feet are installed with metal hangers on 24 inch centers between the purlins, parallel to the beams
2 x 4 inches
Which design of tubular webbing is the standard in rope rescue?
Spiral Weave (also known as “shuttle loom construction”)
What are some of the characteristics of masonry buildings constructed pre-1933?
- Mortar consisting of sand lime only, no cement
- Lack of steel reinforcing rods (“rebar”)
- Brick exterior walls about 13 inches thick
- Parapet walls around the perimeter of a roof. Parapet walls can be there feet above the roof line, and five feet or more if used as a facade on the front of a building
- Floor and roof joists that are “let” (penetrated or resting in a cavity) into the inside of the exterior walls
- Straight roof sheathing
- Roof and floor joists that are “fire cut” (ends were cut with an angle) so they would pull loose from the exterior walls during a firer and collapse into the interior of the building without pulling down the exterior walls
Skylights are usually constructed from ______ or ______.
Glass or plastic
How should the Air Rescue Cushion be cleaned?
The cushion can be cleaned with COLD WATER and a DECK BRUSH; however, this should be done only if absolutely necessary, as it requires placing the cushion out of service until it has dried completely
What is the re-inflation time of the Air Cushion Model 70A?
20 seconds
The midpoint of the rope should be marked with ___ black stripe. The ends should be ___ black stripe for odd years and ___ black stripes for even years.
- Midpoint- 1 black stripe
- Odd years- 1 black stripe
- Even years- 2 black stripes
Positive pressure is most efficient when the exhaust opening is between ____ and ____ the size of the entrance opening.
Between 3/4 to 1-3/4 the size of the entrance opening
The steel tube web members of an open web roof are prefabricated form ___ to ___ inch cold rolled steel with ends pressed flat into a semicircular shape with a hole punch through the end. These flattened ends are inserted into slots in the chords and steel pins (up to ______) are driven through the chord members and web member, completing the assembly.
1 to 2 inch cold rolled steel; up to one inch
When cutting parallel to purlins on a panelized roof, cut ___ to ___ inches inside of the purlins to avoid hitting metal hangers.
4 to 6 inches
After a jumper lands in the Air Rescue Cushion, have the jumper(s) immediately roll off the cushion and allow _______ for reinflation.
Allow 20 seconds for reinflation
The common “on-center” spacing of an open web is ______.
24 inches
The person falling into the Air Rescue Cushion should be instructed to fall as if what?
As if they were sitting down. When falling in this position, the body will naturally rotate causing the person falling to land on the small of the back
Water covers about ___ of the earth’s surface.
2/3 of the earth’s surface
The Rescue Air Cushion is constructed of ______________, which is fire retardant and waterproof.
Vinyl-reinforced fabric
Is crimping plastic pipe allowed to control a natural gas leak?
Crimping plastic pipe is acceptable as long as all tools used to work on plastic pipe are grounded
There are numerous (over ___) elevator manufacturers, each having produced a variety of elevators
Over 60
You should protect ropes and software from extended contact with what?
Chemicals containing alkaline, oxidizing agents, bleaching compounds and acids
What are the advantages of using a bag to store the two-line system?
- The rope can be flaked into the bag faster than it can be coiled
- The bag helps protect the rope from damage while keeping it clean
- The bag has 2 shoulder straps, which makes it easier to carry. If bag is worn on the back while rappelling, the rope will pay out as you descend without tangling
- A bagged rope is easy deploy. Secure the end of the rope and drop the bag over the edge. The rope will flake out of the bag without tangles. The end of the rope shall be secured to the bottom of the bag by tying a figure eight stopper
Large buildings may have open web bar joists used as girders spaced up to ______.
Spaced up to 45 feet
If there is power to the elevator, turn the power off for at least ___ seconds and then back on again. This can reactivate the elevator by allowing relays to reset (at least ___ seconds is necessary to clear any previous programming in the elevator computer).
30 seconds
Normal hoistway doors can be expected to utilize ____ gib blocks.
Two gib blocks
If the stitching of the Air Rescue Cushion comes apart, what should you do?
If the stitching comes apart, the cushion cannot be patched on a seam. The Air Rescue Cushion must be sent to Supply and Maintenance for repair
The Lamella Arch Roof is also known as an _________, _________ or _________ roof.
An egg crate, geometric or diamond-patterned roof
What determines the length of the dice cut?
The length of the dice cut is determined by the reach of the tool being used to pull the sheathing
Book 29 has general guidelines developed by ____________ for loading picket anchor systems in “average” loamy soil.
Developed by the US Army
A single lightweight truss structural member can span ______
70 feet
Transmission lines that distribute natural gas maintain pressures up to _____ psi and use pressure booster compressor stations, at specific intervals, to maintain appropriate flow and pressures.
1,000 psi
TRUE OR FALSE: The mainline and belay line can share the same anchor if it is bombproof.
TRUE. However, they must be attached to the anchor via separate pieces of webbing
TRUE OR FALSE: Facades are usually open or coming to the attic of a building?
TRUE. This is common along with a lack of firer stops in the facade
What are the 4 different settings of the portable monitor and the pump pressures that should be pumped?
- 350 gpm: 105 psi
- 500 gpm: 115 psi
- 750 gpm: 110 psi
- 1,000 gpm: 125 psi
What is a Penthouse Door?
A door leading form the interior stairwell to the roof. Opening the penthouse door can be a quick way to clear smoke out of the stairwell and any hallway that is open to the stairwell
What is the knot efficiency of a Butterfly Knot?
75%
When rappelling, start with ____ bars.
Start with 4 bars
Combined, the total weight of the portable monitor is approximately ______.
Approximately 61 lbs
Where can further information concerning the portable monitor be found?
In the manufacturer’s operation and maintenance manual
Natural gas is _________ than air.
Lighter than air, which results in escaping natural gas rising and rapidly dissipating
