The objectives of this lesson are as under:
- History of hose.
- Define hose (Normal called Water Pipe).
- Describe types and specification of hoses and their couplings.
- Describe the method of storage of delivery hose.
- Characteristics of a good hose.
- Describe the causes of hose damage.
- Describe care and maintenance of hose.
- The Fire Hose Direct Main process
- Demonstrate Hose drills.
1. History of Hose:
The first Hose used was made of leather. It was made only in short lengths owing to its great weight, and this added to the fact it had to be periodically greased to keep it pliable, made it very difficult to handle. The leather hose was followed by hose constructed of natural I fibers. This was known as canvas hose and was first manufactured! in Scotland about 1850. The fibers used were flax, and the hose was woven entirely by hand.
The fire hose cabinet is used in Fire vehicles and in store. And all key hose must be placed in Hose Bags so may be safe from any kind of dust or rust. And fire hose reel is mostly attached at the back side of the fire truck. The fire hose reel cabinet must be covered with a door and locked so while driving the Firetruck the reel may not come out of the position.
2.Definition of Hose (Fire Hose meaning):
Fire hose has been used for hundreds of years for the extinguishment of the fire and is one of basic elements of fireman’s stock in trade. It is1 necessary for the conveyance for water from static supply sources | or form mains hydrants on to the fire. In areas where water may be J in short supply, Hose or Pipe may be necessary to relay water considerable distances, and special large diameter hose been designed for this purpose.
3. Types of Hoses:
The hose may be divided not two categories according to its main use;
3.1 Delivery Hose:
The delivery hose is laid on the delivery side of the pump where the water passing through it is at a pressure greater than that of the atmosphere. The fire hose pressure is measured with working Hose pressure, testing Hose Pressure and Bursting Hose Pressure.
3.1.1 Specifications of Delivery Hose:
Fire hose length >>>>>>>>>> 100 feet.
Diameter>>>>>>>>>> 1-3 Inches
Material >>>>>>>>>> Polyester, Canvas, Rubber.
Type of coupling >>>>>>>>>> Instantaneous type.
Type of binding >>>>>>>>>> Wire binding.
Parts (Fire hose fittings couplings) >>>>>>>>>> Male end, Hose, Female end
Working pressures >>>>>>>>>> 0 to 20 bar.
Testing pressures >>>>>>>>>> 20 to 35 bar.
Bursting pressures >>>>>>>>>> above 35 bar.
3.2 Suction Hose:
This is employed on the suction side of the pump where the water passing through it may at a pressure either below or above that of the atmosphere.
3.2.1 Specifications of Suction Hose:
Length >>>>>>> 10-15 feet.
Diameter >>>>>>> 3-6 Inch
Material>>>>>>> Hard rubber.
Type of coupling >>>>>>> Thread type.
Type of binding >>>>>>> Clump binding.
Types and specification of Couplings:
- Instantaneous type coupling (Quick release).
- Storz type coupling (locking type).
- Thread type coupling.
- Instantaneous type coupling (Quick release).
Diameter: 2.5 Inch (for delivery hoses).
According to diameter (for suction hoses)
Material: Brass, Aluminum, Gunmetal.
Parts: Coupling, gasket, spindle
Type of binding: Clump binding.
2. Storz type coupling (locking type).
3. Thread type coupling.
4. Method of Hose Storage:
The roll method (or coil).
Dutch roll (or roll on the bight).
Figure of eight method.
4.1 The Roll Method:
In this method, the hose is laid out flat on the ground and a start is made at the female coupling. The coupling is doubled down on the hose which is then rolled up until the father end is reached. The hose strap is finally passed through the center of the hose and secured about 6 ins (150mm) behind the outer coupling. The fire hose winder can be used for this purpose.
The rolled hose is normally to be preferred since with instantaneous coupling, the female coupling may be held with both hands and the hose then rotates as it is run out.
4.2 Dutch Roll (or roll on the bight):
The hose should be laid out flat on the ground and the female coupling should be drawn back along the hose towards the other end so that the female coupling lies on top of the hose and about 3 feet (1mm) short of the male coupling. After the upper layer has been arranged exactly over the lower layer, the hose is rolled up from the bight so that the coupling comes together on the outside of the roll. All the hoses rolling methods are to increase the life and efficiency of hoses.
In this method, the hose is doubled back and forward on itself and is subsequently secured at the center of the folds. Its principal advantage is that it permits of running out as fast as a man can move, but the flaked hose is subject to the risk of serious damage due to dragging, particularly over broken glass. This may, to a considerable extent, be obviated by carrying the hose on the shoulder and it to pay out as the man moves away.
4.4 Figure of Eight:
This Is a variation of flaking but it avoids the sharp ends. As the name implies, it is wound in a figure of eight patterns over two bollards. Its chief advantage is that it avoids the tight bends of flaking and the hose can be run out equally well, on the other hand, it takes up considerably more room. This method is undoubtedly the best for storing rubber lined hose.
5. Characteristics of Hose:
The main characteristics essential for a good Fire Fighting hose are;
Hose must be sufficiently flexible to enable it to be handled easily and without kinking when in use and for it to be made up into a smooth roll either wet or dry.
The durability and wearing qualities must be as high as possible and the materials used, particularly in the warp, must have high resistance to abrasion and be able to withstand the rough usage which hose inevitably receives in services.
5.3 Resistance to rot:
Natural fibers such as flax and cotton are liable to be affected by mildew or rot and it is important that these materials, when used in the construction of hose, are given rot proofing treatment.
5.4 Frictional loss:
A rough internal surface increases the resistance to the flow of water through the hose; the surface should, therefore, be as smooth as possible in order to reduce to a minimum loss of pressure through friction.
The weight of hose is important, not only from the point of view of handling at fires and drills, the heavy hose is usually bulky and such a combination may present problems insofar as the load carrying capacity of an appliance is concerned and as regards the locker space available. The maximum weight limit laid down for 2 % inch (70mm) non -percolating hose is 22 ozs (624 g) per yard (914mm) and the use of synthetic materials and lightweight lining has enabled manufacturers to produce a good non -percolating hose having a weight of about 18 ozx (51 Og) per yard (914mm).
6. Causes of Hose Damage:
Emphasis has been laid on the method of fabrication of hose in order that its liability to damage can be fully appreciated. It is important that every fireman should know how to look after the hose in his care and how to keep it in first class condition, ready for any calls which may be made upon it. Much of the damage caused to the Hose is avoidable by the strict carrying out of hose drill instructions. The used fire hose must be cleaned after usage and may not touch with any kind of chemical, dust or rust. The causes of decay in hose are:
- Acids, oils, grease, and petrol.
6.1 Abrasion :
Men should always be thought to lay out hose without dragging it. The question of abrasion is intimately connected with the methods of making up the hose and these are dealt with below. Numerous different methods have been developed for strong hose and these may be listed as. While fire hose nozzle is attached is must be carefully attached os the abrasion may not be generated on any part of the Hose.
Rotting by mildew is a serious cause of deterioration of hose. Mildew is a fungus which, given the suitable condition of moisture and heat, lives and grows in the cellulose of natural fibers such as flax and cotton. Hose insufficiently dried after use or stored in a damp state provides the conditions which promote the growth of mildew, complete saturation prevents active infection as readily as complete dryness and it seems to be established that imperfect drying of a Fire Hose can be guaranteed there need be no mildew problems.
It is not generally realized that shock is a frequent cause of hose failure. The hose should never be thrown roughly to the ground even though they may be dry and in good condition. Shock may of course also arise when water is allowed to flow too rapidly into a line of hose which is badly kinked.
6.4 Acids, Oils, Grease and Petrol:
Some types of fire hose are liable to damage by contact with acid, oil, grease, petrol, etc. and hose should be stored well from these substances. Care should also be taken when working at oil installations and industrial undertakings to ensure that as for as possible hose has the minimum of contact with oils and the like. Petrol, for example, will cause rubber to separate from the fabric. The ruptured, leaked and used hose must be repurposed, recycled and demodified for other means.
7. Care and maintenance of Hose:
The following are general hints on the care of hose which will assist the prolonging its life:
- The hose should be stored in cool, dry, well-ventilated places.
- The hose or Pipe which is unused for long periods of time should not be allowed to remain on the appliances but should be removed and placed on racks or towers.
- If hose becomes frozen it should on no account be bent, as it will be liable to crack.
- Rubber deteriorates more rapidly at high temperature, so rubber lined hose should not be exposed to hot dry nor stored in the sun’s rays.
- Fire hose known to have been contaminated with acids or alkalies should be thoroughly washed immediately with clean water.