Emergency service personnel working in or near moving traffic are killed every year. For example, five responders died in 2000 in highway-related incidents. Almost 8% of the line-of-duty deaths in 2002 were 'struck-by' situations while the responders were working in or near moving traffic.
These deaths have a common bond: in each case, effective traffic control was not accomplished. Traffic accidents cause traffic problems. Traffic problems cause traffic accidents. Working in or near moving traffic is a high risk activity.
When a fire department arrives at a highway crash scene, a temporary work zone must be established. If traffic disruption continues for more than 20 minutes, considerations of the 'temporary" situation must turn into an extended operation.
Any highway incident lasting more than 60 minutes is looked by traffic management authorities as a highway work zone. There is a federal standard for exactly how a work zone must be organized, including warning signs, traffic direction, flaggers, etc.
Prompt traffic control reduces traffic problems at the scene of an emergency and prevents secondary collisions. Although crowd and traffic control are considered a basic police agency function, lack of control of traffic seriously affects the safety of all concerned.
Traffic control must be an integral part of our hazard control activities and is necessary even when personnel are limited in number. Personnel on the emergency scene must learn to use their vehicles as initial traffic control devices.
The ResponderSafety.com website reports that of the five emergency responders struck and killed by moving traffic at emergency scenes in 2000, several were actually on or near the highway fighting fires. Others were directing traffic. An EMS responder was walking along the roadway with her back to approaching traffic when she was struck and killed.
Assistant Fire Chief Jim Yvorra of Berwyn Heights, Maryland, the fire officer to whom the first edition of this author's vehicle rescue book was dedicated, was one of 139 firefighters to die in the line of duty in 1988. He too was a statistic of the hazards of working in or near moving traffic.
While at the scene of a minor vehicle incident on the Washington Beltway, Jim was struck and killed by a passing motorist. His own fire department members responded to his aid but were unable to save his life. From 1979 to 1988, firefighters struck at or near emergency scenes were most often operating at traffic accidents or vehicle fires. Most fatalities occurred after dark or under conditions of poor visibility.
The most critical initial action that can be taken to minimize these unfortunate occurrences is the proper positioning of our emergency vehicles in a 'block' position. A block position places the large emergency vehicle at an angle to the approaching traffic, diagonally across several lanes of traffic.
This position begins to shield the work area and protects the crash scene from some of the approaching traffic. Under normal circumstances, the initial emergency vehicle to arrive at the crash scene should 'block' on the 'upstream' or approaching traffic side of the damaged vehicles.
A 'right block' or 'left block' means that as the responding vehicle arrives on scene, it turns at a right or left angle.
In this block position, the emergency vehicle's lights warn approaching traffic of the presence of the incident ahead. Most importantly, the vehicle acts as a physical barrier between the crash scene work area and approaching traffic.
The block position is best fulfilled by a fire department engine or ladder company apparatus. Rescue vehicles that crews will work off of at the scene should be positioned close enough to the work area to be protected by the engine or ladder truck.
The bigger the vehicle blocking, the better. You want mass between you and oncoming traffic. You want to assume that all approaching traffic will be unable to stop, is being operated by an inattentive driver or that the driver is medically impaired.
If you keep this mindset, you will remain alert to the dangers of moving traffic. Firefighters and EMS personnel do not operate in the unprotected 'upstream' side of a crash scene. All operations take place within the 'shadow', the protected downstream area created by the block from the large apparatus.
When the ambulance arrives at the scene, it must park in a safe 'downstream' position, a position on the departure side of the traffic flow. This requires the ambulance driver to pull past the initial blocking apparatus and around the crashed vehicles. The ambulance must stop at an angle that places the rear patient loading area as far away as possible from any moving traffic.
An upstream block enables the first-arriving officer to survey the scene from inside their vehicle. If the response is at night, the crew can use the headlights and vehicle-mounted spotlights for initial scene illumination. Additional units should either block further upstream from the crash or pull downstream into a safe and protected area. Additional emergency vehicles positioning at the scene will find locations on the downstream side of the scene the safest and most beneficial.
Expressway responses present unique challenges for initial traffic blocking. On any vehicle crash or fire call reported on any of the high-volume, limited-access expressways that run through the city of Plano, Texas for example, an additional fire department vehicle is dispatched on the initial call. Along with an engine company and ambulance, one of the department's tandem-axle ladder trucks also responds. For this crew, their primary function is to create an upstream block for the engine company and ambulance crew working the incident. This crew can also act as the "eyes in the back of the head" for those at the scene.
While other working personnel are intently concentrating on the action at the scene, the ladder truck serves as advance warning to approaching motorists of the situation ahead. This crew can also deploy traffic cones upstream of their apparatus to begin to 'taper' approaching traffic into one or more of the moving lanes of traffic. Should a problem motorist appear, one apparently oblivious to traffic control efforts, the ladder company can use their radio and air horn to warn fellow workers. Having someone dedicated to covering your rear can be a lifesaver!
Establishing the Hot Zone
The area of highest risk at a crash scene is where the crashed vehicles and the patients are located. This primary danger zone is commonly referred to as the 'hot zone', a familiar term used by hazardous materials teams. When no fuel, fire or spill hazards are present at a crash scene, the hot zone extends approximately 50 feet in all directions from the wreckage. The emergency vehicle initiating the first upstream block maintains this 50 foot hot zone spacing if possible. If one or more vehicles involved in the crash are burning, the hot zone distance increases to approximately 100 feet. The hot zone should be expanded whenever there are doubts about the safety and stability of a scene.
If the crashed vehicle is leaking gasoline, the fumes typically travel downhill and downwind to low-lying areas such as sewer drains, along curbs, ditches, and gullies. Because they must be evacuated and have all sources of potential ignition near them isolated, these low-lying areas become extended hot zones. Low areas should be avoided when positioning emergency vehicles or patients. Safe parking at a crash scene involving a utility company power pole requires vehicles and crews to avoid any area under overhanging transmission lines and near power transformers, which could short out. The hot zone should extend one intact pole beyond both affected poles when wires are down at a crash. Command personnel must quickly ascertain the stability of overhead wires, the damaged pole, adjacent power poles, and adjoining spans of transmission wires.
In all situations, if in doubt as to how much space to put between the damaged vehicles and the nearest emergency vehicle, a rule of excess should prevail. If in doubt, stay back for safety's sake. It is far easier and safer to move a vehicle forward than it is to be forced to rapidly back it up or abandon it entirely should an unanticipated, life-threatening situation develop.
Traffic should be kept moving by being detoured or re-routed if possible. Immediate traffic detours that move approaching traffic around and away from the crash scene are recommended. If traffic is detoured and kept far enough away from the crash area, motorists are less likely to slow or stop, causing traffic congestion at the scene. What is to be avoided is the complete stopping of traffic, especially for any extended period. If traffic is stopped completely on a typical high-volume interstate highway and expressway, the traffic jam can extend one mile for each minute that traffic is not moving. After five minutes of total shutdown, the possibility of getting additional emergency service units into or out of the immediate crash scene area becomes extremely difficult and time consuming. A detour around the area minimizes traffic congestion and maximizes scene protection.
Advance Warning Safety Considerations
Making approaching traffic aware of a crash or fire scene ahead can be done by various means. Initially, vehicle emergency warning lights provide notification of the hazard ahead. Operators of emergency vehicles must realize that during night incidents, particularly on two-lane highways, the headlights of their emergency vehicle may totally blind approaching vehicles as they look toward the crash scene. The headlights of any emergency vehicle on the scene that may impair the vision of approaching drivers should be turned off. The driver should use their parking lights only to minimize this problem.
Red-burning highway road flares, a generally accepted means of warning of a traffic impediment, are also inherently dangerous at a crash scene. The burning phosphorus flare can ignite combustible materials or flammable vapors within its flammable range. The residue that spits from a burning flare can cause significant injury to unprotected hands or eyes. Personnel using flares for traffic control should be sure that the flare itself is the only thing present that is going to get burned.
If safe to do so, individual flares can be placed on the approach side of the emergency scene and continued towards approaching traffic at 15-foot intervals. To enhance the visibility of this advance warning during the day or at night, burning flares can be placed close to orange traffic cones. The glow from the burning flare reflects off the cone and illuminates it. As a general rule, the total length of this line of cones and flares should extend from the scene towards approaching traffic a distance equal to twice the posted speed limit in paces. Each pace taken by a responder is estimated at 3 feet in length. For example, where the posted speed is 35 miles per hour, flares and cones are placed every 15 feet for a distance of 70 paces from the crash scene. This is approximately 210 feet.
On a highway where traffic may be expected to be traveling up to 65 mph, the line of flares should extend for at least 300 feet, the length of a football field from goal line to goal line. If the damaged vehicles are located in a limited sight distance situation such as over the crest of a hill or at a curve in the roadway, emergency vehicles, flares and cones should be placed to adequately warn approaching traffic on the other side of the hill or curve. Bad weather can also require that the advance warning to approaching motorists be extended. If in doubt, continue to extend the area of advance warning for approaching traffic.
It must be remembered that flashing lights, flares or traffic cones only warn the fully alert and responsible motorist approaching the scene. Traffic cones and flares only suggest what you want the approaching motorist to do. They will not stop the inattentive or impaired driver from driving right into the scene. Only vehicles, large vehicles at that, can stop an approaching vehicle. At no time should flares, cones, or individuals be blindly relied upon as the sole means of traffic control.
