Ground Ladders Are Vital in Firefighting and Life Safety

Ladder

A ladder is a vertical or inclined set of rungs or steps. There are two types: rigid ladders that can be leaned against a vertical surface such as a wall, and rope ladders that are hung from the top. The vertical members of a rigid ladder are called beams (US) or stiles (UK). Rigid ladders are usually portable, but some types are permanently fixed to buildings. Rigid ladders are available in many forms, such as:

· Fixed ladder – two side members joined by several rungs; a structure with no moving parts

· Extension ladder -fixed ladder divided into two or more lengths for more convenient storage; the lengths can be slid together for storage or slid apart to maximize the length of the ladder; a pulley system may be fitted so that the ladder can be easily extended by an operator on the ground then locked in place using the dogs and pawls

· Step ladder, hinged in the middle to form an inverted V, with stays to keep the two halves at a fixed angle

· Platform steps, step ladder with small horizontal platform at the top

· Orchard ladder, three legged step ladder with third leg made so that it can be inserted between tree branches for fruit picking

· Telescopic ladder, stiles consist of concentric or rectangular tubing that can be slid inside each other for storage

· Roof ladder, rigid ladder with large hook at the top to grip the ridge of a pitched roof

· Cat ladder, lightweight ladder frame used on steep roofs to prevents workers from sliding

· Hook ladder or pompier ladder, rigid ladder with a hook at the top to grip a windowsill; used by firefighters

· Turntable ladder, extension ladder fitted to rotating platform on top of a fire truck

· Bridge ladder, ladder laid horizontally to act as passage between two points separated by a drop.

Rigid ladders were originally made of wood, but in the 20th century tubular aluminum became more common because of its lighter weight. Ladders with fiberglass stiles are used for working on or near overhead electrical wires, because fiberglass is an electrical insulator.

For safety, a rigid ladder should be leaned at an angle of about fifteen degrees to the vertical. In other words, the distance from the foot of the ladder to the wall should be about one quarter of the height of the top of the ladder. At steeper angles, the ladder is at risk of toppling backwards when the climber leans away from it. At shallower angles, the ladder may lose its grip on the ground. Ladder stabilizers are available that increase the ladder's grip on the ground.

· A ladder standoff, or stay, is a device fitted to the top of a ladder to hold it away from the wall. This enables the ladder to clear overhanging obstacles, such as the eaves of a roof, and increases the safe working height for a given length of ladder.

· Rope ladders are used where storage space is extremely limited, weight must be kept to a minimum, or in instances where the object to be climbed is too curved to use a rigid ladder. They may have rigid or flexible rungs. Climbing a rope ladder requires more skill than climbing a rigid ladder, because the ladder tends to swing like a pendulum. Steel and aluminum rope ladders as sometimes used in vertical caving.

· Dissipative ladders are portable ladders built to ESD (Electrostatic Discharge) standard. Electrostatic Discharge is a natural occurrence in which electricity is passed through our body, or other conductor, and discharges onto some object. For example, the shock we feel when we touch a doorknob is an ESD. This natural occurrence is becoming a very hot topic in the field of electronics assembly due to the costly damage ESDs can cause to sensitive electronic equipment. Dissipative ladders are ladders with controlled electric resistance: the resistance slows the transfer of charge from one point to another.

· Pool ladders. A ladder is also used on the side of a boat, to climb into it from the water, and in a swimming pool. Swimming pool ladders are usually made from plastic steps with special grip and metal bars on the sides to support the steps and as handrails for the user.

· Assault ladders. These are designed to be used by units which may need to board or assault vessels or buildings. They can be used when a full sized ladder is not required or when working in confined spaces. Suited for covert operations such as sniper placement, and vessel boarding. It was developed and designed for tubular assaults including buses and trains and for 1st story breaching. Its extra wide design gives the user greater stability, but still can fold away to be stored. It is available in standard aluminum or non-reflective black finish in 6 and 8 foot lengths.

With newer and more technical equipment being introduced to the fire service almost on a daily basis, it is hard to stay focused on basic firefighting. Ground ladders are as basic as you can get; however, they are still as important today as they ever were. When you place a ladder to a window, you have an instant exit for both occupants and firefighters. Place a “roof ladder” on a roof and you have a safe place to start ventilation. Aside from the obvious uses for ladders, others are forcible entry, breaking out windows, and ice rescue.. Of course, do not forget about the occasional “cat stuck in a tree.” As long as rescuing cats does not interfere with more serious firefighting duties, this type of rescue provides training and good public relations. The more you use ladders, the more uses you will find for them.

New firefighters often wonder why they must practice raising ground ladders over and over almost to the point where they no longer have to consciously think about what they are doing. That is exactly the point. Anytime, day or night, snow or rain, heat or cold, firefighters must use ground ladders with practiced skill and also must understand the features and limitations of them.

This concept became apparent to me several years ago at the scene of a 2-story wood frame occupied structure fire. As my crew approached the fire-ground, we noticed a man visible through the lower sash of a double-hung window on the second floor. His outline was obscured by thick black smoke with an orange tint to it, which meant that seconds were numbered. From a different vantage point, another crew observed the same scene. In an instant, both groups bolted for their respective ladder trucks to retrieve the appropriate ground ladders needed to effect the rescue. Both crews returned with exactly the same sizes and types of ground ladders for their job. This was no coincidence. The members of both crews had received their training at different times and by different instructors, but the proper use of ground ladders had been embedded in the minds of both crews, so they responded to the task in the same way.

Unfortunately for us, we came in a close second place, as the other crew beat us to the window and rescued the victim. Obviously, the victim is what really mattered. Keep in mind that the rescue was successful because of ground ladders, not an “articulated telescoping tower ladder” not any other specialized expensive equipment – just ground ladders and firefighters that knew what they were doing. Of course, there are situations that call for special equipment, but the proper knowledge of and use of ground ladders will save lives and reduce property damage at almost every fire.

Story by Peter F. Kertize, Captain, Buffalo Fire Department, New York

Дата добавления: 2014-12-27