Full Fire Fighting & Fire Protection Course - (Part 5)

                     From this part of Fire fighting and Fire protection series onwards, we are going to learn about Fire Fighting Network Components.

Fire Fighting Network Components

1. Standpipe System ( Manual Fire Fighting System )

                Fire fighting system is mainly categorized into two main systems :

* Automatic Fire fighting system &

* Manual Fire fighting system.

            Standpipe system comes in the category of Manual Fire fighting System.

Standpipe Fire Fighting System Design

A standpipe firefighting system consists of a water supply line connected to a standpipe where the water supply line is attached to a hose. A hose connects the standpipe to the nozzle. There are two types of nozzles, either a fixed barrel or a telescoping barrel. The fixed barrel nozzle is a single piece connected directly to the standpipe while the telescoping barrel nozzle is a multi-piece device that folds down.

Benefits of Using a Standpipe Firefighting System

The first advantage of using a standpipe firefighting system is that it keeps the firefighter’s clothes dry. If they were to use a different type of nozzle, their clothes would get wet due to the amount of water being sprayed out. Another benefit is that the standpipe prevents dirt/debris from getting stuck inside the nozzle.

Types of Standpipes

Standpipes come in many different sizes and designs. Due to these differences, each type has its own advantages and disadvantages. Many people choose the straight pipe design because it is easier to install. However, it may be difficult to find materials for the bends. On the other hand, the L-shaped pipe design makes installation easier. It is less costly compared to the other two styles and is a good choice if you have a small space to work in.

Standpipe Nozzle Fittings

There are three different ways to attach the standpipe nozzle fitting to the standpipe. Each fitting type is slightly different with slight variations in the way the fitting works. The most commonly used fittings are the top and bottom threading. These types of fittings allow the nozzle to slide onto the fitting easily and securely.

 Common Problems Associated with Standpipes and Firefighting Systems

Using a standpipe firefighting system requires enough water flow rate at a constant pressure. It is imperative to maintain a steady flow rate. Most issues arise when there isn't sufficient water in the main line. As the water level drops, the weight of the water causes the main line to sag. When the sagging occurs, the water flow rate decreases making it harder to fight fires.

If the line is clogged, then the water pressure increases causing the water stream to break off. When this happens, the spray pattern becomes wider and the stream becomes erratic.

Another issue arises when a person uses the wrong size nozzle. If the nozzle is not correctly sized, then the spray pattern won’t be even. In addition, the stream could become uneven and unpredictable.

                    Standpipes are pipes placed underground near waterways, where water flowing over the pipe collects and drains into the waterway. In firefighting operations, standpipes are often filled with water to extinguish fires at ground level. Standpipes may be designed to drain directly into a river (as opposed to being drained into a pond), and thus require no pumping or siphoning, so they are more environmentally friendly than conventional pumps.

The use of standpipes dates back thousands of years; ancient Greek soldiers were first recorded using them to fight fires, and the Romans employed them extensively. The Romans also realized that if water was directed downhill away from a burning structure, it would tend to flow away from the flames themselves.

Standalpipelines have been in use mainly in Australia since the early 1930's. In 1934, the New South Wales government passed legislation requiring local authorities to place standpipes around their towns, and in 1939 the Queensland government followed suit. By 1965, standpipes had become commonplace in many cities and towns throughout both states, although the majority of these pipelines remain hidden beneath footpaths, parks and roads today.

Today, standpipes are still widely used in rural areas, for example in North East Victoria, where they are particularly useful. The construction of a single standpipe can cost less than $5000, and the maintenance costs of each standpipe are minimal. A typical standpipe has a capacity of 2–3 million litres per hour.

Since they do not need any electricity, standpipes are ideal for remote locations, and therefore can be used in bushfire prone regions. In addition, a significant number of standpipes are located close to bodies of water, making them suitable for flood mitigation as well.

A standard standpipe consists of a circular cast iron cylinder buried to a depth of between 10cm and 30cm below ground. A horizontal flange is welded to the top of the cylinder. Smaller diameter pipes connect to the standpipe, diverting water from the standpipe into smaller channels leading to a network of catchment tanks. These tanks collect rainwater and deliver it via small pipes to the standpipe, ensuring continuous water supply even during dry spells.

Modern standpipes are fitted with sprinkler heads, which direct water outwards in a cone shape. When triggered, the sprinklers create a fine mist in the desired direction. To ensure that the standpipe does not fill completely, the pressure inside is kept low until the standpipe outlet valve opens. As soon as the valve opens, pressure builds rapidly, causing the water inside the standpipe to shoot outwards in a powerful jet. The force of the jet carries the water up to heights of 150m.

Although standpipes are primarily used for firefighting, they are capable of delivering an effective chemical spray as well. The use of standpipes for firefighting is widespread, and they are likely to be included in any firefighting plan.

While some people prefer the convenience of having a pump nearby, standpipes offer several advantages over pumps. First, pump stations can fail, and when this happens, water could end up flooding neighbouring houses. Standpipes are installed deep enough underground to prevent water flowing back into the street. Second, pumps cannot always reach fires at ground level, whereas standpipes can. Third, standpipes deliver water more effectively than pumps. If a pump fails, the standpipe will continue to operate, sending water to the correct location.

Pumps are also notoriously noisy, which makes them unpopular with neighbours. At night, they can produce a loud noise, especially if the pump motor is left running overnight. Standpipes are comparatively quiet. Depending on the size of the pipe, the average speed of sound can be about 120km/h. In contrast, the average speed of a truck can be around 60 km/h.

It takes approximately 1 litre of water to move a person 5 metres horizontally. However, the force of a jet can send water at speeds of up to 300 km/h. Hence, a human being caught in a stream of water coming from a standpipe would only experience minor injuries, unless he or she was struck by a piece of debris. Water travelling at such high speeds is unlikely to cause serious injury.

In fact, standpipes are designed to protect those who might get hit by falling debris. Because the water comes from a standpipe, the area immediately surrounding the pipe should be relatively free of obstructions. Falling branches or trees hitting the pipe would only damage the pipe itself. On the other hand, if the standpipe is damaged, the water will stop flowing and the danger of drowning increases. Standpipes have therefore been designed to withstand normal impacts.

Standpipes generally consist of a cast-iron cylindrical body, surrounded by concrete. The bottom half of the standpipe (the portion nearest the ground) is made of solid metal, while the upper half is hollow. This design prevents objects from getting lodged in the standpipe. The inner surface of the hollow section is lined with rubber to reduce friction.

Standpipes are very resistant to corrosion, except for the inner surfaces of the pipes, the valves, and the fittings. Corrosion can occur if the standpipe is exposed to salt water, or if there are rusty parts within the pipe. When this occurs, rust appears on the outside of the pipe and damages the internal lining. After removing the affected parts, clean the interior of the standpipe with boiling hot water and soap. Dry the entire standpipe thoroughly before reinstalling.

The standpipe fire-fighting system is a combination of water and steam and is used to extinguish fires inside buildings. Steam is created using hot water (80°C) and air pressure (at least 2 bar). Steam, being lighter than water, rises above the water level and condenses to release its latent heat and therefore evaporates the water inside the building. Water is then supplied to the top of the condensing tower, where the condensed steam drops back down and mixes with the incoming water. The resulting mixture of water and steam flows out of the standpipe and is discharged at the bottom.

The Standpipe System is a method of water supply where the fire department connects a hose nozzle to a standpipe using a standpipe connection. By pulling the trigger on the nozzle, firefighters create enough pressure inside the pipe to force water out. This is accomplished through the use of a valve called a standpipes valve, or SPV. To put the standpipe system in practice, we have to consider flow rate versus volume.

We know that the larger the standpipe, the higher the flow rate (gallons per minute) due to friction of the water molecules hitting the sides of the pipe. However, if we increase the size of the standpipe, the volume of water contained inside the standpipe increases. Therefore, increasing the size of the standpipes increases the amount of time it takes for the water to travel down the length of the hose. Since time is directly related to distance, the amount of time it would take for the water to travel from the pump to the nozzle increases. As a result, the flow rate decreases.

To counteract the decrease in flow rate, we need to double the number of standpipes valves used. Using two valves instead of one doubles the area where the velocity is high and reduces the time it takes for the flow rate to drop off. So in order to maintain a constant flow rate, we need twice the number of standpipe connections that we had before. In this example, we had five connections, so we doubled the number to ten connections.

The final step in building the standpipe system is to connect the pipe to the water source. We do this by connecting a tee fitting to either a hydrant or fire hydrant.

A standpipe is any device or pipe designed to collect water from a supply line and direct it into a vessel (usually a reservoir) at ground level. A standpipe may be mounted above ground or below ground (as in a water well), but almost always consists of a vertical cylindrical casing surrounding the supply line, with a diameter slightly less than that of the supply line.

Standpipes are pipes installed at a height above ground level connected to a water reservoir. Water is pumped out the standpipe by gravity, and then sprayed onto the fire. When water is sprayed directly onto the flames, it extinguishes them quickly without causing damage to the surrounding area. If the standpipe is too high above ground, firefighters will need buckets or nets in order to catch any sparks that may fall off the fire.

The working of Standpipe Fire Fighting System

It is designed to deliver water at high pressure to extinguish the fire. In case of fire, water is forced under pressure onto the flame. The use of standpipes in firefighting is well known since ancient times. Standpipes are used in different ways, depending upon their construction, purpose, dimensions, location and type of fire they are used to fight. In general, standpipes may be classified as follows : -

(i) Single-stage standpipes (ii) Two- stage standpipes

(iii) Multiple-stage standpipes

(iv) High-pressure standpipes

(v) Special types of standpipes

(vi) Other types of standpipes.

2. Types of Standpipe:

There are various types of standpipes according to the application. These include : -

(a) Horizontal single-stage standpipe

(b) Horizontal double-stage standpipe

c. Vertical single-stage standpipe and

d. Vertical double-stage standpipe.

Standpipe should have adequate length to reach the source of fire; otherwise, it would not work properly.

Standpipes are pipes that are placed at a desired location for water supply purposes. Standpipes have been used for various purposes over time. A typical example of a stand pipe would be a well pipe. These pipes can be seen in many different places today including residential homes, offices, schools, hospitals etc. Most often these pipes are connected to a water supply network either directly or indirectly. One of the major uses of standpipes is to provide potable drinking water to the public. Standpipes are often seen in rural areas where potable water supply networks do not reach. Since stand-pipes do not require any electricity they are perfect for use in remote areas. In addition to providing potable water to the public, standpipes are also used to fight fires. Fire fighters use them to direct huge amounts of water onto a burning structure and thus put out the flames. Usually standpipes are made of iron and are buried deep underground. However, it's possible to build them above ground too. There are two types of standpipes namely vertical standpipes and horizontal standpipes.

Vertical standpipes consist of a central pipe extending vertically underground with several branches coming off it. Each branch terminates at manholes located near the ground level. Water flows down the center pipe and the branches connect to the manholes on each side of the pipe. Horizontal standpipes are similar to vertical standpipes except that the pipes are horizontal instead of vertical.

The operation of standpipes are quite simple; the flow rate of water is controlled using valves. The valve is attached to the standpipe and controls the pressure inside the pipe. When the valve opens, water flows through the pipe until the pressure drops below the threshold value. Once the pressure drops below the set point, the valve closes and stops the flow of water.

Withstandpipes are normally used in situations where access to electric power is difficult. Moreover, these pipes are generally installed to protect critical infrastructure. Thus, it is recommended to install these pipes properly. The pipes should be buried deeply enough so that no damage can occur if they break. If you are planning to dig a hole to bury the pipe make sure you know what type of soil it is because some soils tend to expand if dug. If you notice the soil expanding after digging you should wait till it returns back to its original state before you continue digging. Make sure the pipe is buried securely and the top cover is sealed properly otherwise it may leak and cause flooding. Also, check whether the pipe is leaking or not. Check the joints between the pipe and the cover. If they are loose then tighten them with suitable tools. Lastly, make sure that the standpipe is protected from lightning strikes. So, there you have it. You now know everything about standpipes.

Access all the previous parts of this full fire fighting series by clicking the links provided below:

Part 1 --- Click Here!!!

Part 2 --- Click Here!!!

Part 3 --- Click Here!!!

Part 4 --- Click Here!!!