Head (device)
A ladder is a device for climbing up and down with rungs fitted into two stiles on the left and right. In contrast to common usage, ladders are referred to as journeys in mining .
There are ladders made of wood , steel , aluminum and plastic . Ladder types are ladders that z. B. be leaned against a wall, ladders that can stand freely, ladders that are wholly or partially on one level (e.g. roof), and permanently installed ladders. A fundamentally different design are the rope ladders and hanging ladders that are not standing on the floor, but hanging .
history
Tree trunks provided with notched steps are the preliminary step of today's ladders. There is uncertainty about the beginning of the use of wooden ladders; in the 3rd millennium BC They were probably already known in the settled cultures of Egypt and Mesopotamia . It is also unclear whether the stepping sticks fitted into the side bars from the start or were connected to them with cords. Rope ladders are likely to be a little younger and are closely related to the development of stable ropes . In the originally-storey residential buildings ladders found to a lesser extent than in using the most multi-storey defense and storage buildings - as the most in about 2.50 to 3.50 m in height located were high inputs medieval Bergfriede accessible only by ladders.
The original shape of today's folding ladder was invented in Italy in 1600. In 1761 the first extension ladder was built; later this ladder was placed on a chassis.
Until the second half of the 20th century, wood was the preferred material for ladders. They were mainly made by hand, for example in the Thuringian wood country, and the ladder makers also traveled around, sold their products or repaired defective ladders directly at customers' sites. Since the 1960s, aluminum has been widely used as a conductor material because it is lighter and more durable, but wooden ladders are still common for some special purposes, such as electricians , since wood is non-conductive.
Portable ladders
Portable ladders are generally ladders that can be carried by one or more people. This means that these ladders can be used flexibly and quickly in different locations.
Portable ladders for the fire brigade and other aid organizations
The fire brigade and THW in particular make use of the advantages of portable ladders . In Austria they are preferably made of light metal . where they are standardized in ÖNORM 4047. Portable ladders serve as an alternative, usually second, escape route for people from a burning house or attack route for fire fighting . In addition, they can be used as improvised rescue equipment for other tasks (e.g. for water and ice rescue, for support, etc.). In addition, such ladder types can also be used outside of emergency organizations.
The use of portable ladders in German fire services is laid down in fire service regulation 10. Only ladders in accordance with the standard (see below) may be used. Here the working height or the deployment height is referred to as the rescue height .
Extension ladder
A ladder that is very often used in the fire service is the extension ladder , as it can be used in many ways. Depending on the purpose and required height, up to four ladder sections can be plugged into one another. Fire fighting vehicles are usually loaded with a two or four-part extension ladder.
She can be used as an assistant manager, i. In other words, it needs a fixed object against which it can be leaned at a 65–75 ° angle (e.g. house wall, tree). It is also possible to use it as a ladder stand, but then it must not be climbed, only e.g. B. can be used as a hose bridge. Furthermore, a ladder section can also be used as a makeshift stretcher or to rescue people who have broken into the ice.
According to the DIN EN 1147 standard, the following lengths result for ladders made of light metal:
| Ladder length | Headroom | |
|---|---|---|
| 1 ladder section | 2,660 m | approx. 1,963 m |
| 2 ladder sections | 4,570 m | approx. 3,873 m |
| 3 ladder sections | 6.480 m | approx. 5,783 m |
| 4 ladder sections | 8,390 m | approx. 7,693 m |
This enables the second floor to be reached safely with four ladder sections.
The difference between the conductor length of several parts and the sum of the length of the individual parts results from the overlapping of the parts when plugging together. The rule is that the parts each overlap 52.7 cm and each additional part extends the ladder length by 1.910 m.
For Germany, in the current model building regulations (MBO) or in the state building regulations, in addition to the turntable ladder, only the four-part extension ladder is considered as rescue equipment for the second escape route. It must be possible to rescue the four-part extension ladder from a window or balcony with a parapet height of eight meters. To save people, this is still possible with the four-part extension ladder at a 75 ° angle.
According to the relevant accident prevention regulations, more than four ladder sections may not be plugged together. In individual cases, longer extension ladders have been used to rescue people in emergencies; however, this is solely the responsibility of the head of operations. During use, the extension ladder is usually carried out by three or four firefighters.
A distinction is made between so-called A-parts and B-parts: The A-parts also have rungs on the ladder foot so that they cannot be placed on a ladder part. An A-section is always the lowest part of the ladder. In the case of B-parts, the bottom two rungs are missing, so another part can be attached. For a while it was common to use a B-part instead of an A-part, into which a short piece with two rungs was inserted. In the meantime it has been abandoned again. There is also a connecting part to connect two ladder parts to a so-called step ladder, but then the ladder may no longer be climbed (see above).
The ladder is held together by connections made of sheet steel, which are fastened on the inside or outside of the bars, which firmly hold the ends of the other end of the ladder. In addition, the assembled parts are locked by means of a spring bolt.
There are extension ladders made of light metal or wood. The stiles of the wooden extension ladder are made of spruce, pine or larch wood, the rungs that are glued in the stiles are made of ash. The ladder is given additional stability by additional rung anchors.
Stepladder
A stepladder consists of two B-parts, or a B-part and an A-part. One ladder section is crossed with the foot end at the head end of the other ladder section and the crossing points are secured by means of a mast throw on each side.
After the ladder has been set up, it is secured with a fire line from one rung of one ladder to the rung of the other ladder. On the one hand, this prevents the ladder sections from shearing and on the other hand makes it possible to regulate the inclination of the ladder sections. Subsequently, for example, hoses can be laid over this or it can be used as a fixed point for a hoist. In order to use a step ladder as a fixed point, a standpipe is placed as a pulley in the twisting of the top of the ladder, over which the rope is guided. The fire brigade can thus rescue from manholes with simple means.
For the standardized ladder parts, however, there are also industrially manufactured ladder connecting parts for making a step ladder from two or even 4 ladder parts. In addition, this connecting part has an eyelet underneath for attaching a pulley or hoist, for example Rollgliss . However, only one ladder section per side is permitted.
Hose transfer (bridge)
A hose bridge consists of at least 3 ladder sections, whereby the horizontal ladder sections can be extended by up to 2 ladder sections.
Such a hose bridge is generally erected when it is foreseeable that a water delivery route will be laid over a road for a longer period of time. It is a substitute for conventional hose bridges, which have the disadvantage that they cannot be crossed for cars with little ground clearance and severely inhibit the flow of traffic. However, a hose bridge made of ladders has the disadvantage that larger vehicles (e.g. trucks) cannot drive through it.
The structure is similar to a stepladder. The horizontal ladder sections are interlaced with the vertical ladder sections, with the feet inclined outwards. Then they are secured with mast throws. To bring more stability to the construction, a diagonal line can be inserted on each side. In order to secure the ladder against falling over, a tether (4 in total) is attached to the crossings of the ladders on each side, with which the hose bridge can be erected and with which it is then secured at fixed points. It is advisable to lay the hose lines over the ladder sections in a dry state before erecting them and to have a hose line available as a replacement.
When erecting the hose bridge, at least 4 people are required, 2 on the holding lines in the direction of the erection and 2 for lifting. Once it has been erected, the holding lines must be attached to fixed points (vehicle, tree, etc.) and the ladder feet must be secured against traffic. For this purpose, pylons must be set up at the feet of the ladder and a fire brigade must be parked with a warning flag or trowel.
Extension ladder
The two or three-part extension ladder is a leaning ladder made of two or three movably connected ladder parts that can be pulled apart with a pulling rope. The individual parts are prevented from being "retracted" by so-called drop hooks. In addition, the ladders generally have a rope brake .
The standardized three-part variant has a transport length of 5.60 m when pushed together, and 14 m when fully extended. This enables a rescue height of 12.20 m or reaching the 3rd floor. It also has two support rods, which are attached to the side of the lower part to increase stability when setting up or to enable a free standing. In the free state, that is, the ladder is not z. B. Leaning against a building, it must not be extended. According to FwDV 10, three-part extension ladders must be set up by two teams (corresponds to four fire brigade members).
The two-part variant has an operating length of 9.70 m and can reach the 2nd floor. Lower, middle and upper ladders each have 17 rungs. A wooden extension ladder weighs 100 kg, the aluminum version is significantly lighter at 75 kg.
Folding ladder
The folding ladder (also double ladder ) is a leaning ladder of the fire department . According to the standard (see below) it has a folded length of 3.26 m, when unfolded a length of 3 m and is therefore the only standardized ladder whose transport length is greater than the length of use. When folded, the folding ladder has the shape of a square timber with rounded corners. It takes up little space and can easily be stowed in a vehicle.
The folding ladder is well suited for overcoming small differences in height and for use in narrow spaces or shafts. The folding ladder has 9 rungs and weighs about 10 kilograms. The spars are usually made of spruce, pine or larch wood, the rungs are made of ash wood and are additionally covered with sheet steel. The wooden parts of the folding ladder are oiled with linseed oil and coated with a layer of clear varnish.
Hook ladder
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The hook ladder used to meet fire brigade standards, which is no longer the case today (see below) . It is 4.40 m long and has a hook on the top with which it can be hung in a higher opening. It must not be used as a leaning ladder, as it is only designed for tensile loads, but not for pressure loads. Since, as described above, for. B. can be hung on every balcony or in every window, its working height as the only ladder is practically unlimited.
It is rarely used, for example when other types of conductors are not suitable. Hook ladders with steel hooks (68 cm) weigh 11 kg, ladders with light metal hooks (70 cm) weigh around 9 kg. The hook has 11 teeth so that the ladder cannot slip off after hanging. The tip of the hook is bent downwards. Two deflectors on the lower side of the ladder ensure that there is sufficient distance to the wall or wall. The stiles of the hook ladder used to be made of pine, larch, spruce or ash wood, the rungs, which were reinforced with additional rung anchors and wedged and glued into the stiles, were made of ash wood. A galvanized steel wire on the inside of the stiles ensured that the ladder remained usable even in the event of stile damage. Nowadays, hook ladders made of aluminum with a titanium-reinforced steel hook are common.
The hook ladder is usually carried out by two people, but only ever climbed by one person (both troop people climb one after the other from floor to floor). In addition to the use of the ladder in an emergency, it is also used in fire fighting competitions in the hook ladder discipline .
Multifunctional ladder
The so-called multifunctional ladder is listed as a multi-purpose ladder in the latest standards for rescue vehicles and - as an alternative to the four-part extension ladder - for fire-fighting group vehicles and emergency fire-fighting group vehicles . Even with two multifunctional ladders in accordance with DIN EN 1147 Supplement 1 and a clip-on part, an installation height of eight meters on the parapet (i.e. the second floor) can be achieved.
Norms
There are the following standards for portable ladders for fire brigades and aid organizations:
| ladder | Standards ( EN , DIN , ÖNORM ) |
|---|---|
| Extension ladder | EN 1147, DIN 14711, ÖNORM F4047 |
| Extension ladder (3-part) | EN 1147, DIN 14715, ÖNORM F4047 |
| Extension ladder (2-part) | DIN 14714 (standard withdrawn) |
| Folding ladder | EN 1147, DIN 14713, ÖNORM F4047 |
| Hook ladder | EN 1147, DIN 14710, ÖNORM F4047 (standards for hook ladder withdrawn) |
| Multifunctional ladder | EN 1147 supplement 1 |
With the entry into force of the agreements of the member states of the World Trade Organization (WTO) against the restriction of free competition and trade through technical standards - in particular the "Agreement on Technical Barriers to Trade" (TBT) - the standards for the safety of portable ladders and portable stairs are obsolete and may no longer be used as legal rules as long as it has not been scientifically proven that technical standards, design descriptions or operating instructions for portable ladders and portable stairs are harmful to health or lead to an impairment of national security if they are not observed. Since this evidence is missing, the certification of portable ladders and stairs according to the present standards within the WTO states for a legal regulation of the safety when handling ladders has become obsolete.
More portable ladders
Step or trestle ladder
A stepladder or trestle ladder (in Austria double ladder ) is a ladder made up of two parts connected to each other by joints. To prevent the ladder from spreading unintentionally, both parts are connected with a chain or a bracket.
Fruit ladder
The fruit ladder is a free-standing ladder with i. d. As a rule, a support whose hinge is in the top of the ladder. Because it is set up on three points, it can also be used well on slopes.
Leaning ladder
The leaning ladder, also called leaning ladder, is the most common ladder in the commercial and private sector after the stepladder. It consists of two stiles and rungs in between. It is available in a wide variety of lengths and materials. In addition to the one-piece leaning ladder, there is also the 2- or 3-part leaning ladder (extension ladder, where you can move the ladder parts to reach greater heights). The maximum standing height for leaning ladders is 7.00 m.
Multipurpose ladder
The multi-purpose ladder consists of three ladder parts, which can be used either as a “three-part leaning ladder (extension ladder)” or as a “step ladder with two risers and a support part”. The multi-purpose ladder always has an additional stand cross member for stability.
Stepladder
A step ladder or household ladder is a stepladder with three to eight steps. It consists of two interconnected parts (ladder part and support part), which are often designed conical for stability. The stepladder has a pedestal as the top step. This is intended to enable the user to stand securely and to engage in a cross strut of the support part. The compact design enables the stepladder to be stored in a space-saving manner.
Roofer ladder
A roofer's ladder is a ladder, usually made of wood. It is usually placed on the roof and into appropriate roof hooks mounted. It has flat bars and is flexible. The rungs are arched upwards so that the (firmly shod) foot still has enough free space up to the roof surface to be able to step on the upper edge of the rung unhindered with the middle of the foot.
Single stile ladder
Single stile ladders have only one stile (also known as the Tyrolean climbing fir), from which the rungs extend in both directions. Because there is only one stile, this type of ladder can also be used in difficult terrain without any problems, for example when harvesting fruit, see climbing tree . They are also used by divers on boats as they can be climbed with flippers on.
Other types of ladders
Stair ladder
A fixed access with an incline of 45–75 ° is called a stair ladder. (see stairs incline )
Vertical ladder
A fixed access with a gradient of 75–90 ° is referred to as a fixed ladder. (see stairs incline )
Endless ladder
The endless ladder is a training device for fire brigades and other units that was used at the beginning of the last century. The electrically operated exercise device has round rungs spaced apart from normal ladder rungs, which are endlessly mounted on a chain. Its function is similar to that of the paternoster lifts that used to be common . Activated by means of a light barrier or manual switch, it “runs” at an adjustable rate of climb of around 3 to 25 m / minute until the set “climb height” is reached.
Turntable ladder
Turntable ladders are aerial rescue vehicles of the fire brigade. Depending on the type, they can be up to 50 m and higher. A simplified and outdated form of the turntable ladder is the trailer ladder .
Robber ladder
The robber ladder is not a ladder in the classic sense. She is a ladder made up of at least one person; a kind of support is created by clasping the hands and creating a step surface. This can now be used as the first rung by another person. The second rung is usually the shoulder.
Ladder wall
The ladder wall is a competition element of the fire brigade . It serves as an obstacle that must be overcome in competitions of the youth fire brigade and in the 4 × 100 meter fire brigade relay for adults. The wall is 2 m high and at least 120 cm wide. Four boards are attached horizontally to two vertical supports. The upper edges of the boards are at a height of 50 cm, 100 cm, 150 cm and 200 cm above the track. The thickness of the boards is 4 cm to 6 cm and their width 10 cm to 15 cm.
Wall bars
The fortified in gyms on the wall instructor for physical training is a ladder or wall bars respectively.
Rope or Jacob's ladder
Fire escape
Fixed vertical ladders, often with back protection, which serve as escape routes from buildings.
Use and maintenance
The load limit is generally one person per ladder section or the corresponding manufacturer's information.
Leaning ladders may only be placed at fixed points (e.g. house walls) on solid ground. The angle of attack should be approx. 65 ° to 75 ° and the ladder should protrude at least three rungs over a possible entry opening.
Wooden ladders may only be painted with clear varnish so that cracks or other damage remain visible.
Climbing techniques
When climbing a ladder, a distinction is made between two techniques, the pass and the cloister .
See also
literature
- Instructions for handling ladders and steps. (PDF) BGI 694 information sheet from the professional associations and the German statutory accident insurance
Web links
Individual evidence
- ^ Franz-Josef Sehr : Development of fire protection . In: Freiwillige Feuerwehr Obertiefenbach e. V. (Ed.): 125 years of the Obertiefenbach volunteer fire brigade . Reference 2005, ISBN 978-3-926262-03-5 , pp. 114-119 .
- ^ Ostthüringer Zeitung: The last original ladder maker in Germany
- ↑ Portable ladders In: Manual for the basic training of volunteer fire brigades. Retrieved December 3, 2015.
- ↑ a b Fire Brigade Regulations 10 . The portable ladders . Committee on Fire Brigade Matters, Disaster Control and Civil Defense (AFKzV), Federal Office for Civil Protection and Disaster Aid, 1996.
- ↑ a b DIN EN 1147 supplement 1 (2012-08-00)
- ↑ JT Demel: Rescue height of the 4-part extension ladder in relation to MBO, FwDV 10 and DGVU. In: https://www.demel-net.de . JT Demel, November 6, 2017, accessed November 6, 2017 .
- ↑ Use of an eight-part extension ladder for rescuing people in 1987 Cologne In: Der Feuerwehrmann. 12/1987.
- ↑ a b Thomas Zawadke: Portable ladders. In: The red booklets - compact training. 204. Kohlhammer Verlag, 2005.
- ↑ LFV Bayern (2014): Technical information on portable ladders for rescuing people. Use of the multifunctional ladder according to DIN EN 1147 ( Memento from March 4, 2016 in the Internet Archive ) (PDF) Supplement 1 - Portable ladders for the fire brigade according to DIN EN 1147.
- ↑ https://www.obstleiter.de/