Drivers Test

Smooth finish waterway contributes to both shape and reach of stream

Used on handlines @ 50 psi

Used on master streams @ 80 psi

• GPM - gallons per minute
• 29.7 - constant
• d - diameter of orifice
• NP - nozzle pressure

Flows are usually 350 gpm or greater

Fog master streams @ 100 psi

Smooth bore master streams @ 80 psi

• NR - nozzle reaction
• 1.57 - constant
• d - diameter of nozzle
• NP - nozzle pressure

• NR - nozzle reaction
• 0.0505 - constant
• Q - total flow thru nozzle in gpm
• NP - nozzle pressure in psi

• FL - friction loss
• C - friction loss coefficient
• Q - flow rate in hundreds of gpm
• L - hose length in hundred of feet

10 psi for each appliance in hose assembly when flowing 350 gpm or more

25 psi in all master stream appliances

• 
• 

• EP - elevation pressure
• H - height

Standard for Fire Apparatus Driver/Operator Professional Qualifications

Reject for hearing loss of 40 decibels or more @ 500-1000-2000 Hz

Reject for hearing loss of 40 decibels or more @ 500-1000-2000-3000 Hz

Required that firefighters have a corrected far visual acuity of 20/40 with contact lenses or spectacles

Standard on Fire Department Occupational Safety and Health Program

Standard for Automotive Fire Apparatus

• Intake/discharge pump connections
• Pump and engine controls and gauges
• Hoses - intake, supply, attack

Minimum pump capactiy - 750 gpm

• Aerail device
• Ground ladders
• Water tank
• Fire hose
• Fire pump - at least 750 gpm

As per NFPA 1901, must carry at least 1000 gal of water

Standard for Aircraft Rescue and Firefighting Vehicles

• ABS - reduce chance of skid
• Apparatus must be brought to complete stop from speed of 20 mph in at least 35'
• Parking brake must hold apparaus on 20% grade
• Air pressure must bulid up w/in 60 sec
• Air Pressure Protection Valve - prevents operation of air horn if reserviour drops below 80 psi

To restore or replace that which becomes inoperable

Keeping the apparatus in state of usefulness or readiness

Standard for Emergency Vehicle Technician Professional Qualifications

• Wash frequently w/cold water to harden paint
• Use garden hose w/o nozzle to apply water - stream from end of hose no longer than 1 foot
• Never remove dust/grit by dry rubbing
• Use good automotive shampoo
• Do not use extremely hot water or wash while surface is hot
• Rinse loose dirt prior to shampoo and water
• Use approved solutions to remove grease/tar
• Dry vehicle with clean chamois

Should not be applied until paint at least six months old

As rule of thumb, it is generally best to keep fuel tank at least 3/4 full at all times

Turns various lights on at specified intervals so that start-up electrical load for all devices does not occur at same time

Watches system for added electrical loads that threaten to overload system; When overload occurs, load monitor will shut down less important electrical equipment to prevent overload (load shedding)

• Check for proper adjustment and reaction
• Steering wheel play should be no more than 10^o in either direction
• Steering wheel w/20" diameter equals about 2" play in either direction

• Check each lug nut by hand for looseness
• Check for proper tire inflation as recommended by manufacturer
• Check valve stem condition
• Check tire condition - proper tire type, tread depth, tread seperation, and wear

The distance that the pedal must be pushed before the throw-out bearing actually contacts the clutch release fingers

Allow apparatus to move forwar @ 5 mph, push down on brake pedal firmly - apparatus should stop within 20'

• Society of Automotive Engineers; indicates viscosity of oil
• Do not mix different types of engine oil

• Produce hydrogen gas when being charged
• Red cable to +
• Black cable to frame

• Flush pump with clean water
• Check and clean intake strainers
• Check pump gear box for proper oil level and traces of water
• Operate pump primer w/all pump valves closed
• Operate change over valve
• Check packing glands for excessive leaks
• Operate pump pressure control device
• Test accuracy of foam proportioning system

To get apparatus and crew to scene in expedient, yet safe and efficient manner

• 20% - 25% caused by vehicle collisions
• 25 firefighter deaths per year by vehicle collisions and rollovers
• Intersections most frequent and most severe

• Improper backing of apparatus
• Reckless driving by public
• Excessive speed by fire apparatus driver
• Lack of driving skill and experience by driver
• Poor apparatus design and maintenance

• Losing control of apparatus on a curve or adverse road surface - which may cause vehicle to leave road surface, roll over, or strike another vehicle/object
• Driver unable to stop in time to avoid collision with another vehicle/object

• Overconfidence in one's driving ability
• Inability to recognize dangerous situation
• False sense of security b/c of good driving record
• Misunderstanding of apparatus capabilities
• Lack of knowledge about how to operate controls of apparatus in emergency

42% of all collisions - driver not aware of problem until too late to correct it

• Often overloaded
• Have high centers of gravity
• On chasiss that were worn out before conversion
• Water tanks improperly baffled
• Chasiss not designed for the weight of water

• One gallon of water weighs 8.33 lbs
• One gallon of gasoline weighs 5.6 lbs
• One gallon of fuel oil weighs 7.12 lbs

• Concerning speed
• Direction of travel
• Direction of turns
• Parking

• Pertain to dry, clear roads during daylight conditions
• Adjust speeds for wet roads, darkness, fog, or any condition that makes driving more hazardous

Occurs when the throttle is applied while the transmission in in too high a gear for given set of conditions

• Result in the use of 1/2 gallon of fuel per hour
• Buildup of carbon in injectors, valves, pistons, and valve seats
• Misfiring b/c of injector carboning
• Damage to turbocharger shaft seals

Set engine to idle at 900 - 1,100 rpm

• Anticipate other drivers actions
• Estimate visual lead time
• Know braking and reaction times
• Combat skids
• Know evasive tactics
• Have knowledge of weight transfer

• Aim high in steering
• Get the big picture
• Keep your eyes moving
• Leave yourself an "out"
• Make sure others can see and hear you

The sum of the drivers reaction distance and the vehicle's braking distance

The distance a vehicle travels while a driver is transferring the foot from the accelerator to the brake pedal after perceiving the need to stopping

The distance the vehicle travels from the time the brakes are applied until the apparatus comes to a complete stop

Can project 300' in front of vehicle

Can project only 12' or less in front of vehicle

Units should travel at least 300 - 500 feet apart

• Driving too fast for road conditions
• Failing to properly appreciate weight shifts of heavy apparatus
• Failing to anticipate obstacles
• Improper use of auxiliary braking devices
• Improper maintenance of tire air pressure and adequate tread depth

• Practice looking 12 sec ahead on city streets
• 20 sec ahead on highways

Approx 0.4 sec in the time from which the driver pushes down on the brake pedal until sufficient air pressure is sent to the brake to operate

• Always travel in the innermost lane on multilane roads
• Avoid passing vehicles on their right side
• Make sure you can see that the opposing lanes of traffic are clear of oncoming traffic if you must cross the center line
• Avoid passing other emergency vehicles if at all possible

• In snow deeper than 8"
• When vehicle moving slow or in reverse

Standard for a Fire Service Vehicle Operations Training Program

• Alley dock
• Serpentine course
• Confined space turnaround
• Diminishing clearance
• Road test

Equal to 1 1/2 times the height of building

• Building less than 5 stories - pumper inside and aerial outside
• Building more than 5 stories - pumper outside and aerial inside

• Position as close as possible to FDC
• If hydrant nearby - connect to both the hydrant and FDC

• Identify suitable drafting locations during pre-incident plans
• Minimize lift distance
• Connect hose and then move apparatus into position
• Hard intake should not rest on bottom of water source

Consists of an intake hose conneciton on the shore and length of pipe equipped with strainer that extends into water supply source

• Should be at least 15" above ground level
• Should be 2' of water all around strainer

• Preferred type of connection to hydrant is large diameter intake hose
• Intake hose sections commonly 10' - 50' long
• If front wheels of apparatus turned to a 45^o angle, driver can easily adjust distance to or from hydrant by moving unit forwar/backward

• Stop short of hydrant
• Put two full twists in hose to min kinks
• Sexless couplings - no twist; may come apart
• Avoid injury - stand behind hydrant when opening valve

• Stop pumper few feet short
• Aim pumper in direction of hydrant @ 45^o

• Only when max flow not needed or when LDH unavailable
• Limits amount of water available
• High amount of friction loss

• One strong hydrant supplies two pumpers
• Better use of water
• Shorter hose lays
• Second pumper supplied by water passing thru first pumper (connected intake to intake)

• Short form of relay pumping
• More pressure needed than single engine able to supply
• First pumper connects to water supply and then "pumps" water thru discharge to next pumper
• Pumps acting in series

• Structure protection
• Direct fire attack

• Level I - more than one unit responding to incident
• Level II - large number of emergency vehicles responding to same incident; need staging officer
• Staging officer - communicates resource availability to IC or planning section
• Companies in staging must be ready to respond w/in 3 min

• At least one lane of traffic should be closed off
• Apparatus should be placed between flow of traffic and firefighters working the incident
• Apparatus act as shield - positioned at angle
• Front wheels turned away from incident
• Position additional apparatus 150' to 200' behind shielding apparatus to act as barrier

• First arriving unit should never procede until material is identified
• Approach incident from upwind and uphill

Area surrounding the incident that is closest to the release and may have been contaminated by release material

• Area abutting hot zone and extending to the cold zone
• Used to support workers in hot zone
• Used to decontaminate personnel and equipment exiting hot zone

• Encompasses warm zone
• Used to carry out all other support functions of incident
• IC, staging, and triage/treatment located within cold zone

• Treat every rail as active
• Never position truck on rails
• Try to position unit on same side of tracks as incident
• Run hose beneath rails or use aerial apparatus to run hose on over top of area

• Most common fire extinguishing agent
• Between 32^o and 212^o exists as liquid
• Below 32^o - solid, ice
• Above 212^o - gas, water vapor
• Considered to be incompressible
• Heaviest close to freezing
• Lightest close to boiling point

British Thermal Unit - the amount of heat required to raise the temperature of 1lb of water 1^oF

Measure of heat-absorbing capacity of substance

Temperature at which liquid absorbs enough heat to change to vapor

• Force per unit area
• A 1 in² column of water 1' high exerts a pressure at the base of 0.434 psi
• 2.304' of water column exerts pressure of 1psi at the base

• Fluid pressure is perpendicular to any surface on which it acts
• Fluid pressure at a point in a fluid at rest is the same intensity in all directions
• Pressure applied to a confined fluid from without is transmitted equally in all directions
• The pressure of a liquid in an open vessel is proportional to its depth
• The pressure of a liquid in an open vessel is proportional to the density of the liquid
• The pressure of a liquid on the bottom of a vessel is independent of the shape of the vessel

• Atmospheric
• Head
• Static
• Normal operating
• Residual
• Flow

• At sea level - 14.7 psi
• Pressure of 1 psi moves column of mercury raise 2.04"
• At sea level Hg = 14.7(2.04) = 29.9"

Pressure less than atmospheric

• Height of water supply above discharge orifice
• To convert head in feet to head pressure: divide # feet by 2.304
• The number of feet that 1psi will raise 1in² column of water

• Pressure found in water distribution system during normal consumption demands
• Difference between static and normal operating pressure is the friction caused by water flowing thru various pipes, valves, and fittings in system

Part of total avialable pressure not used to overcome friction loss or gravity while forcing water thru pipe, fittings, fire hose, and adapters

Forward velocity pressure at discharge opening while water is flowing

Refers to the center line of pump or bottom of static water supply source above or below ground level

Position of object above or below sea level

• Movement of water molecules against each other
• Linings in the fire hose
• Couplings
• Sharp bends
• Change in hose size or orifice by adapters
• Improper gasket size

• All other conditions the same, friction loss varies directly with the length of hose or pipe
• When hoses are same size, friction loss varies inversely as the fifth power of the diameter of the hose - that's the advantage of larger size hose
• For a given flow velocity, friction loss is approx the same, regardless of the pressure on water

• Pressure of 30,000 psi required to reduce the volume of water 1%
• Same volume of water supplied to fire hose under pressure at one end will be discharged at other end
• Size of hose determines velocity for given volume of water
• Smaller the hose, greater the velocity needed to deliver same volume

Velocity increased beyond limits, friction becomes so great that entire stream is agitated by resistance

• Decrease hose length
• Increase hose diameter
• Remove sharp bends in hose lay

Water flowing thru pipe or hose suddenly stopped results in energy surge being transmitted in opposite direction - often at original pressure

• Source of water supply
• Means of moving water
• Water processing or treatment facilities
• Water distribution system, including storage

• Ground water
• Surface water

• Direct pumping
• Gravity
• Combination systems

• Coagulation
• Sedimentation
• Filtration
• Addition of chemicals, bacteria, or other organisms
• May also add oxygen/fluoride

• Grid system
• Feeder
• Secondary feeder
• Distributors

• Recommended size of pipe for fire hydrant supply mains is 6"
• Cross connecting mains no more than every 600'

• Indicating - shows wheter valve is open or closed
• Nonindicating

• Periphery
• Deflection
• Impinge

• Monitor - stream direction and angle can be changed while water being discharged
• Turret pipe - deck gun
• Deluge set - fixed, direction and angle cannot be changed while discharging water
• Elevated master stream - placed on end of aerial device

• Broken stream nozzle
• Water curtain nozzle
• Piercing nozzle
• Chimney nozzle

• Select finger to which desired flow has been assigned
• Multiply the number at tip of finger by first digit at base of finger
• Examples:
• finger one - 2(1.0)
• finger seven - 7(3.5)

• Rotary or piston types
• Use positive action to move air and water
• Used to expel air - priming pumps

• Impeller and casing
• Water inroduced into eye of impeller
• Impeller rotates at 2,000 - 4,000 rpms
• Greater speed of impeller - greater pressure developed
• Impeller mounted off center

Two stage pump - both impellers receive water from source and delivers to discharge

• Two stage pump - water introduced to first impeller and then discharged to next impeller and then discharged to create greater pressure
• Less volume

• Light blue - Class AA - 1500gms or greater
• Green - Class A - 1000 - 1499 gpm
• Orange - Class B - 500 - 999 gpm
• Red - Class C - less than 500 gpm

• Create negative pressure in pump
• Atmospheric pressure will force water up hose into pump
• Increasing height of pump will decrease total pump capacity
• Max amount of vacuum most pumps develop is approx 22" Hg

• Should be a min. of 2' of water all around strainer
• Object can be placed over strainer to prevent whirlpool effect
• Low level strainers sit at bottom allow water to be drafted to depth of 2"
• Best indication of cavatation is lack of reaction on pressure gauge to change in throttle setting

20'

• Two stage pump should be in parallel
• Engine set between 1000 and 1200 rpm for primer pump
• Operate primer control until all air removed and steady stream of water is discharged
• Entire priming requires 10-15 sec
• Most common cause of inability to prime is air leak
• Common place for blockage is at strainer

• First arriving engine should located FDC and nearest hydrant
• Indication of actual fire, min. of two 2 1/2" hoselines should be connected to FDC and supply line to hydrant
• Confirm presence of fire prior to pumping into system
• Rule of thumb to discharge 150 psi into FDC

• Do not use house or standpipe lines - house lines provided for occupants
• Fire attack crews bring own hoselines
• Connect attack lines to standpipe outlet near point of attack - usually on floor below fire floor

Contain water under pressure and are redy to be used as soon as lines can be attached to outlet

• Must be supplied with water from a pumper that attaches to standpipe FDC
• Time delay when charged b/c of air that must be expelled from system

• Pressure loss in standpipe (25 psi)
• Friction loss in hose lay from pumper to FDC
• Friction loss in hose on fire floor
• Nozzle pressure for type of nozzle employed
• Elevation pressure due to height of building

• Elevation difference between the static water supply and pump intake
• Pump higher than water source

• The max. height to which any amount of water may be raised thru a hard intake hose to the pump
• In most circumstances, max.lift is no more than 25'
• At max. lift, the volume of water available is too low to be of practical value

• Height a column of water may be lifted in sufficient quantity to provide a reliable fire flow
• Every fire pump should have a dependable lift of a least 14.7'
• All fire pumps rated when drafting from a lift of 10' thru 20' of hard intake hose

Lakes, ponds, streams, rivers, and oceans

• Cisterns
• Private water storage tanks
• Ground reservoirs
• Swimming pools
• Agricultural irrigation systems

• Uses a pumper at water supply source to pump water under pressure to next pumper in line
• This pumper boosts pressure to supply next pumper
• Until water is reaches attack pumper

• Pumper connected to water supply
• Should be pumper with largest pump capacity

• In-line pumper(s) connected within relay that receive water from source or another relay pumper
• Boosts pressure then supplies water to next pumper in relay

• Engine located at scene that will be receiving water from relay
• Supplies attack lines and appliances as needed for fire suppression

Carries a mile or more of LDH (4" or larger)

Allows late arriving apparatus to hook up after relay is operating and boost the pressure w/o interrupting the relay operation

• Amount of water required at emergency scene
• Distance from emergency scene to water source

Keep pressure throughout relay @ 175 psi

• Water tenders deliver load to scene, travel to fill site, reload, and return to scene and deliver water - repeat.
• Require pumpers and tenders

• One on each side
• One on the rear
• Gravity dumps - usually 8" or largerJet dumps - small diameter in-line discharge inserted into piping of large tank discharge

• Prevents tank collapse
• Vents need to be completely open

• Must be proportioned and aerated before use
• To produce quality fire fighting foam, foam concentrate, water, air, and mechanical aeration are needed

Raw foam liquid in its storage container before being combined with water and air

Device that introduces foam conentrate into the water stream to make the foam solution

Miture of foam concentrate and water before the introduction of air

Completed product after air is introduced into the foam solution (finished foam)

Standard for Low-, Medium-, and High-Expansion Foam

• Induction
• Injection
• Batch mixing
• Premixing

• Hydrocarbons - float on water
• Polar solvents - mix with water
• Some Class B foams will work on both
• Class B foams designed only for hydrocarbons will not extinguish polar solvent fires
• Many foams intended for polar solvent fires may be used on hydrocarbon fires

• Foam works by forming a blanket on burning fuel
• Foam blanket excludes oxygen and stops burning process
• Water in foam is slowly released as foam breaks down - providing cooling effect on fuel

• Effective for fires in structures, wildland settings, coal mines, tire salvage, and other incidents involving similar deep seated fuels
• Can be proportioned at different concentrates to achieve specific objectives (0.1 - 1.0%)
• Dry foam (thick) - adjust to higher percentage; suitable for exposure protection and fire breaks
• Wet foam (thin) - foam rapidly sink into fuel's surface; adjust to lower percentages
• Reduce surface tension of water, providing better penetration
• Shelf life of 20 yrs
• Avoid direct skin contact - corrosive and supercleaning characteristics

• Pails - 5 gallon, most common for fire service
• Barrels - 55 gal
• Tote tanks - 275 gal
• Apparatus tanks - 20 - 200 gal

20:1 - 20 parts finished foam for every part foam solution

20:1 - 200:1

200:1 and greater

• Roll-on method
• Bank-on method
• Rain-down method

$15

Will be used to change, alter, or amend fire dept rules and regs and shall be kept in a permenant file

Will cover a specific instance where rules and regs will be changed, altered, or amended for a specified period of time and may be kept in a permenant file

Used to change, alter, amend, or clarify fire dept policy or procedures and for information of a permenant nature. Shall be kept in a permenant file

Will cover a specific instance where policy and procedure will be changed, altered, or amended for a specified period of time and may be discarded when period terminates; letters of appreciation and commendation will be posted for 30 days and then discarded

1 1/4 working days per month

1 1/4 working days per month

• Request in writing
• Not to exceed 90 days
• Any request over 30 days to one year must be submitted to the chief and forwarded to city manager for approval

Asst chief shall visually check license of each member every three months

Captain shall notify chiefs of any accident that may disable appartus to the extent that it cannot proceed to emergency. On minor accidents where apparatus is able to proceed to emergency, a person shall be dropped off to obtain detailed info with names and addresses of all witnesses

All officers required to visually varify that all drivers have valid drivers license daily

• Barrel length 2" - 4"
• Choice of make of weapon left to individual carrying firearm; weapon must be kept clean and in good working order
• Modification for any on or off duty weapon is forbidden except to replace grips, sights, or refinish the firearm
• Required on or off duty weapon shall be a .38 or .357 caliber double action revolver, with a five or six shot capacity; or a 9mm or .45 caliber semi-automatic with special approval from the fire chief
• Carrying a firearm on duty, in the capacity of Peace Officer who is not in a distinct uniform shall wear his badge of office on his/her belt in plain view, on the sam side of the weapon

• Shall include a demo of a working knowledge of firearm to range personnel
• Also require that officer complete a designated range course
• Range course fired for score; passing score must be obtained for each weapon registered with the department that will be used while acting as Peace Officer
• Qualification shall require a passing score of 70% for every weapon
• Qualification shall require that the score and description of weapon used in obtaining the score shall be kept on file

While on duty, all firefighters acting in capacity of peace officer must be properly armed; while off duty officer may use discretion whether or not to carry firearm

• Officer shall at all times handle all firearms in a manner not to endanger the life of another officer, firefighter, or any innocent bystander
• Dept inspection of firearm may be made at any time w/o notification by fire chief or designated appointee
• Any firearm that does not meet dept standards shall be removed and officer may be disciplined

• No officer shall carry any of the following:
• Armor piercing rounds
• Tracer ammo
• Glaser safety slug
• Exploder rounds
• Officers shall only carry ammo, on or off duty, that has been approved by dept

Specialist I shall be under supervision of admin specialist II

Fire chief or fire marshal or any officer or member of fire dept designated by fire chief shall have the right or authority to enter any building or upon any premises in the city of brownsville at any reasonable business hour for the purpose of making investigations consistent with the duties imposed therein

The fire marshal or fire chief shall have the authority at all times, day or night, when necessary in the performance of their duties to enter upon and examine any building or premises where any fire has occurred or any adjoining buildings or premises when in their judgment it is proper to do so

All investigations of arson or attempted arson shall be done under the supervision of the fire chief

• Hair not allowed to grow below top of collar
• Sides shall not extend below top of ear lobe - 1/3 of ear must show
• Females must have hair securely pinned up - no flammable hair spray
• Hair shall be well groomed whether max length or shorter
• Sideburns - must not extend below bottom of ear lobe and not extend forward into seal area of mask; No hair in seal area
• Mustache must be neatly trimmed and not extend below corner of mouth; Handlebar not permitted
• Beards - not permitted; Must be clean shaven on duty

• Salute national colors and national anthem while in uniform
• Not in uniform - shall stand at attention and remove headgear as colors pass

Notify asap and no later than 24 hrs

Pumps and all hose be flushed with hydrant water for at least 20 min

• Any member who assumes the tour of duty for another member also assumes all duties and responsibilities pertaining to the tour of duty
• If for some reason the member assuming tour of duty cannot report to duty for any reason, he is to notify his Assistant Chief and make an effort to find a replacement in this place

• Members on duty or in uniform shall not enter or visit any bar, lounge, parlor, or club where liquor is sold or served except in the line of duty
• No member in uniform on or off duty shall enter a liquor store to buy liquor

No member shall circulate any petition relating to any dept policy unless received prior approval by fire chief

On or off duty, drinking or in possession of intoxicants while on duty or loitering where intoxicants are sold while in uniform is prohibited

• Strictly prohibited
• When responding on the same street, units shall respond in a single file at a distance of at least 150' apart

• Permissible to use siren when making an emergency run
• Sirens shall be used as little as possible w/in 200' of any hospital zone

• Shall not stop apparatus in front of a fire hydrant
• All apparatus when at a stop, shall be parallel with and as close as possible to curb
• No apparatus or car shall be parked w/in 50' directly behind a ladder truck

• Commanding officer shall notify dispatch to activate fire marshal
• No salvage or overhaul to begin until released by arson investigator

• Dead person found at scene - do not disturb body unless to prevent further damage or destruction
• Notify commanding officer, who will notify fire dispatch, who will notify homicide division, medical examiner, and fire chief

• Must be turned over the commanding officer, who will in turn give them to owner after proper identification
• Report of contents and valuables turned over to individual will be submitted to fire chief
• No proper identification available or owner cannot be found - property shall be sent to chiefs office along with report

• Use CO₂ or dry powder extinguisher when possible to prevent water damage
• Postal authorities shall be notified

• Commanding officer first at scene shall try to determine cause of fire based on evidence at scene
• If unable to determine - call fire marshal/arson investigator

• Any member arrested or incarcerated must report the incident to his immediate shift commander or fire admin immediately
• Any violation of this rule may be cause for disciplinary action

Members shall not give any written statement concerning an accident of a fire dept vehicle to anyone, unless a member of city's legal department is present

• Must have valid drivers license in possession while operating vehicle
• Failure to advise of any negative changes may lead up to disciplinary action

• Excessive speed prohibited
• When responding to alarm and light is red - driver shall slow down and stop if necessary until all traffic has stopped
• Upon approaching a stop sign, slow down and do not proceed until other vehicles yield right of way

• Driver shall walk around vehicle to ensure no obstructions or personnel in the area
• Look-out man - stationed at rear of vehicle