Among the huge variety of various designs of modern staircases, special fire variants of these products stand apart. One of the features is that the production requirements for them are more stringent than for any other. Particular attention is paid to the materials used, the overall design design and strength characteristics. The classification of fire ladders fully reflects the thoroughness with which they are suitable for their production, because the products can serve in case of extreme situations. Moreover, in such circumstances, they should not fail.
What are the fire escape
In the current realities, all types are used, but each of them can radically differ from the rest. The main types are listed below:
- manual fire escape;
- evacuation to remove people from buildings in which a fire occurred;
- vertical for lifting firefighters to the roof or to windows on the upper floors of a burning structure.
If the first type in the above classification of stairs is considered manual or mobile, then the last two are stationary. In the case of the latter, pre-installation is required directly during the construction of the building. Such structures are described in detail in any project plan, and their presence is a mandatory requirement under current law. In addition, there are spiral staircases that are used by rescuers during fire fighting.
Description of the vertical structure
The location and species characteristics may vary depending on how the roof swings are located and how tall the house is. Fire-technical classification of stairs provides for the installation of structures without fences in the event that the height of the building does not exceed six meters. If this parameter at the building is from six to twenty meters, then a different kind of construction is prescribed. With such a height, it is imperative to make fences, otherwise there is a high chance of people getting injuries if they fall.
For some, it may be unexpected that such stairs are not designed to evacuate victims. These structures are actually used only so that firefighters can climb the upper floors of the building. Fastening of vertical stairs is carried out using anchors, the strength of which is not to be doubted. To evacuate people from a house more than twenty meters high, special marching stairs are installed. You can learn more about them later.
Outdoor Marching Stairs
Such products must meet a number of requirements, including increased safety parameters and convenience for the evacuation of a large flow of victims in the shortest possible time. According to the regulations, the number of steps between two separate sites should not exceed eighteen pieces. Each of the stairs in this design is called a march. There are also some exceptions to the rules. For example, if a staircase consists of only one march (two platforms), then the number of steps may exceed the number indicated above.
All products at the factory undergo mandatory anti-corrosion treatment, which allows them to maintain reliability and structural integrity in the conditions of snow, rain or an excessively high level of humidity in the street. According to the requirements for stairs (the classification of which was discussed above), it is imperative to create the most lightweight basis possible. For these purposes, a special flooring on the steps in the form of a grill is used. Thus, snow or dirt will not get in the way underfoot, as they flow in the slots between the metal. As a result, the steps will not be slippery, which means that people will not receive additional accidental injuries and will not delay the general flow.
Internal escape stairs
With this view, security is ensured in any multi-story building. In this case, not only the technical design parameters of the structure are important, but also the materials from which it will be made. Of the acceptable options, the use of concrete and metal is allowed. Paints must also meet a specific request, and their surface must be refractory.
The flights of stairs themselves are deliberately surrounded by walls on all four sides in order to maximally protect the evacuated people from fire and smoke. The surrounding material also meets all refractory properties. In all of the above structures, wood and plastic can not be used. In addition, the manufacture of products from any materials capable of releasing toxic substances during fire is not allowed.
Manual fire escape
Such designs stand out in a separate subspecies, which also has several types. The manual fire escape classification includes three main options, listed below:
- stick;
- assault;
- retractable.
Each of the types, as a rule, is present among other equipment that is transported by each fire truck. Thanks to these structures, rescuers can penetrate the upper floors and timely carry out emergency or evacuation work. A huge advantage of products is their lack of need for a source of electricity for operation. All of these types have improved strength indicators, which, in turn, ensures the stability, speed and safety of firefighters.
Manual stick ladders
This is called a relatively low, but very reliable design. The number of steps in it does not exceed eight pieces. The folded version looks like an ordinary metal stick with ringed and rounded ends. At first glance it seems that such a device can do little to help because of its low height, but professional firefighters will not agree with this opinion. That is why the classification, purpose and design of manual fire escape are of interest to many. Their application is multifaceted:
- ram when opening locked or obstructed doors;
- rise to the windows of the lower floors;
- stretchers for victims;
- emergency ladder for emergency rescue operations directly inside the burning rooms;
These are the main use cases. In addition, a folded stick can be used as the simplest percussion instrument. Thus, for example, it is possible to repel plaster and other coatings for rescue operations.
Manual assault stairs
If the previous option could help to get into the openings of the first floors, then the attack is used to climb to the very top. There are no restrictions on the maximum height, because the design of the staircase requires the passage from one window to another in turn. Products of this type are widely used not only to save lives, but also as an attribute of one of the disciplines of fire-applied sports.
The main purpose, however, remains purely professional. The classification of manual fire escape ladders by designation indicates that they are used where other options are not suitable, including poles and retractable. Among the design features, the following should be highlighted:
- increased reliability is ensured by the presence of metal ties at the first, seventh and twelfth steps;
- to the end there is a narrowing of the hook, but this does not change its strength properties along the entire length;
- there are thirteen steps in total, fastened on two supporting bowstrings;
- along the perimeter of the stairs are steel safety cables, which are laid in grooves on the bearing supports on the reverse side;
- a steel hook is fixed on the tenth and twelfth steps;
- bowstrings at the lower ends are specially pointed and strengthened by the so-called shoes for leveling the slip and protect the entire structure from damage;
- reliable coupling of the hook with the windowsill is ensured by the presence of four teeth and additional stiffeners.
Manual three-knee ladder
Unlike the previous ones, it carries additional opportunities for rescuers. The only fire escape in the classification that can help raise all the equipment required for the operation to the roof of a two-story house or to the window of the third floor. The design is somewhat more complicated than that described above, and includes three identical metal profiles, a special mechanism for reaming (unfolding), as well as the possibility of fixing the position and back folding.
All profiles have twelve steps and can be advanced directly between the bowstrings of the previous one. The lightness of the three-legged ladder allows you to wear it alone. However, the application is available only for two people. Despite the existing wall supports at the lower and upper ends, someone must certainly insure another fireman from below. The manual principle of operation involves stretching the rope so that the ladder decomposes, and for folding it should gradually weaken this rope.
Stairwells and stairs
The division occurs into two main types with subspecies. You can distinguish ordinary and non-smoke stairs and stairwells. Their classification implies the presence of a total of five subspecies listed in the list below:
- Ordinary stairs and stairwells. Divided into L1 and L2. The first have natural light on each floor through openings in the walls with or without glass inserted. For the second subspecies, light is passed through the holes in the coating itself.
- Smooth staircases and stairwells. Subdivided into H1, H2 and H3. The first have an entrance from the floor through the outer air zone through open passages. H2 has air in the cell during a fire. For the latter, on each floor there is a vestibule-gateway. At this point, air is blown up during a fire or on an ongoing basis.
Features of verification and testing
The audit is carried out at least once every five years. For all types of products, certain loads are provided that they must withstand. Along with verification, tests are also carried out for compliance with the specifications declared during manufacture.
If any of the parameters does not comply with the regulation or part of the structure has been damaged, then the staircase is removed and then repair work is carried out. If it is not possible to restore full functionality, then the design is completely decommissioned and replaced with a new one.
Types of stairs inside buildings
Materials for the manufacture of products for the premises can serve as flammable wood, as well as more reliable concrete and metal. It all depends on regulatory requirements and a particular type of construction. The classification of stairs in buildings includes basic, auxiliary, fire and emergency. The two latter requirements are much stricter in manufacturing.