APPARATUS AND METHOD FOR TESTING A FIRE EXTINGUISHING SYSTEM

Abstract

The present invention relates to an apparatus (10) for testing a water sprinkler system (12) having a wet side (16) and a dry side (14) separated by a valve (18), comprising a fan (24) configured to be coupled to an inlet (42) of the water sprinkler system (12). The fan (24) is configured to provide a supply of pressurized air through the water sprinkler system (12) from the inlet (42) to one or more outlets of the water sprinkler system (12). A sensor arrangement (26) is coupled or operatively associated with one or more of the outlets (22) of the water sprinkler system (12) and is configured to measure the air pressure at one or more outlets (22) of the water sprinkler system (12) and then emit one or more output signals indicative of the air pressure at one or more outlets (22).A communication arrangement (34) transmits one or more output signals from the sensor arrangement (26) to a processing system configured to determine from said one or more output signals the air supply flow rate at one or more outlets (22).

Description

APPARATUS AND METHOD FOR TESTING A FIRE EXTINGUISHING SYSTEM FIRES FIELD OF INVENTION This refers to an apparatus and method for testing a fire extinguishing system, in particular, but not exclusively, a water sprinkler system. BACKGROUND OF THE INVENTION Fire suppression systems are a critical safety component of any large building or facility. In the oil and gas industry, for example, the primary suppression system in both offshore and onshore installations typically takes the form of a water sprinkler system capable of rapidly distributing a large volume of water over a given target area. Unlike fire sprinkler systems, which consist of a network of sprinkler outlets held in a closed position until activated, a water sprinkler system has a dry side, comprising a network of pipes and outlets that are kept open, and a wet side connected to a main water line or other water supply. The dry and wet sides of a water sprinkler system are separated by a valve known as a sprinkler valve.When the sprinkler valve opens, water enters the dry side of the water sprinkler system and is dispensed over the target area through the network of pipes and open nozzles until the sprinkler valve closes. Given the safety-critical nature of fire suppression systems, water sprinkler systems must undergo regular testing and maintenance to ensure they can operate effectively when needed. Typical problems with water sprinkler systems include internal corrosion, deposit corrosion, and / or marine growth, any of which can restrict water flow in the piping network and / or block sprinkler nozzles. Conventional testing techniques involve a wet path test, whereby the water sprinkler system is activated for a test period, for example, 30 minutes, and the system is manually checked for blocked or restricted nozzles by operators wearing appropriate personal protective equipment. This may involve placing a number of receptacles beneath specific areas of the water sprinkler system to collect the dispensed water. The collected volume of water is then compared to the expected volume to determine if the system is operating within expected parameters. Modeling systems have also been developed by CQQfren / eznz / q / Y IVIA / computer models the specific water sprinkler system being tested and calculate the expected fluid pressures at the nozzles using pressure sensors. Two locations are checked: near the inlet; and near the nozzle farthest from the inlet. When the wet test is performed, the pressure readings taken are compared to the modeled pressure values ​​to determine if a problem exists. There are a number of disadvantages to conventional techniques and equipment. For example, conventional wet testing techniques—including computer modeling systems—rely on wet tests performed whenever information on the condition of the water sprinkler system is required. However, wet testing, by its very nature, depends on large volumes of water being dispensed in operational areas, typically for a test period of approximately 30 minutes for each region of the facility being tested. As such, it is recognized that wet testing a large facility, such as an oil and gas installation, will involve a significant amount of time during which normal operations are restricted. Before each wet test, sensitive equipment must also be placed in bags to protect it from the water supplied during the test, which is time-consuming and may not be reliable. Exposing such sensitive equipment to water flow risks equipment failure, requiring repair or replacement at significant expense, causing inconvenience and lost revenue. Also, staff are susceptible to being exposed to the flow of water and therefore must wear protective clothing that may impede their mobility and ability to perform their duties. Exposure to water from wet testing can also cause corrosion in the installation, particularly in offshore oil and gas facilities due to the marine environment. In fact, since offshore installations typically use seawater for wet testing, the required regular wet testing regime can actually exacerbate corrosion and influence the choice of water sprinkler system. Furthermore, because seawater contains marine organisms, the use of wet testing also results in marine growth, which can also affect the choice of water sprinkler system. Other fire suppression systems include nitrogen fire suppression systems where nitrogen gas is used to suppress a fire by reducing the oxygen content within the affected area to a certain point. CQQfren / eznz / q / Y in which the fire will be extinguished. SUMMARY OF THE INVENTION The aspects of this description relate to an apparatus and method for testing a fire extinguishing system, such as a water sprinkler system or an inert gas fire suppression system. According to a first aspect, an apparatus is provided for testing a water sprinkler system having a wet side and a dry side separated by a valve; the apparatus comprises: a blower configured to be coupled to a water sprinkler system inlet, the blower configured to provide a supply of pressurized air through the water sprinkler system from the inlet to one or more water sprinkler system outlets; A sensor arrangement coupled or operatively associated with one or more of the water sprinkler system outlets, the sensor arrangement configured to measure the air pressure at the one or more water sprinkler system outlets and output one or more output signals indicative of the air pressure at the one or more outlets; and a communication arrangement configured to carry one or more output signals from the sensor arrangement to a processing system configured to CQQfren / eznz / q / Y IVIA / determine from one or more output signals the flow rate of the air supply at one or more outlets. In use, the apparatus is operable to perform a test on the water sprinkler system by flowing low-pressure gauge pressurized air through the water sprinkler system and measuring the air pressure at one or more outlets, in particular but not exclusively a plurality of outlets, of the water sprinkler system during a selected test time period. The device eliminates the need for regular wet testing to verify that the sprinkler system will operate effectively when and if required. This has several significant benefits. For example, the device eliminates the time, expense, and inconvenience involved in preparing for a wet test, such as setting up receptacles to collect the water dispensed from the sprinkler system and bagging sensitive equipment, as well as the time, expense, inconvenience, and inaccuracies involved in actually performing the wet test. Personnel are also not exposed to the water flow and are therefore not hindered from carrying out their duties. The device's ability to perform a sprinkler system test without the requirement of a wet test also reduces the risk of corrosion in the system. IVIA / water sprinklers and elsewhere in the facility. Furthermore, the device occupies a relatively small footprint on the installation. This is particularly beneficial in offshore oil and gas installations, such as platforms or equipment, where deck space is typically limited and may prevent conventional testing equipment from being permanently installed. The apparatus may comprise or take the form of a permanent installation in the installation to be tested. At least part of the apparatus may be configured to be permanently attached to the water sprinkler system. It shall be acknowledged, however, that at least part of the apparatus may comprise or alternatively take the form of a temporary and / or retrofitted installation in the installation to be tested. At least part of the apparatus may be configured to be removably attached to the water sprinkler system. The apparatus may comprise, be coupled to, or be operatively associated with, the processing system. In some embodiments, the processing system, or part of the processing system, may be part of the apparatus. Alternatively or additionally, the processing system, or part of the processing system, may be coupled or operatively associated with the system. For example, the processing system may be located in one or more remote locations. The remote location may comprise or take the form of a mobile device such as a tablet, mobile phone, or similar. Alternatively or additionally, the remote location may comprise or take the form of a control room. Alternatively or additionally, the remote location may comprise or take the form of a data store, such as an online data store. As described above, the processing system is configured to determine the air supply flow rate at one or more outlets. Testing a water sprinkler system involves evaluating the system's density application rate, that is, whether the system is capable of delivering the required water flow rate to a given application area in order to suppress a fire. The density application rate is given by: Density Application Rate — (flow rate output) (coverage area) The coverage area is fixed and determined by the design of the water sprinkler system and any modifications made after installation. However, the flow rate from the outlet(s) may vary if restrictions are present within the water sprinkler system. At low gauge pressure, air replicates the flow of water. Therefore, when determining the flow rate of the CQQfren / eznz / q / Y air from one or more outlets Q (liters / min) , the sprinkler system can be tested without the wet testing requirement. The upstream flow rate and pressure are unique to the system state; that is, if pressure is plotted against flow rate, all points on the graph are unique to the system state. This is particularly useful when plotting for a clean system. The device can be configured to operate in different modes. For example, the device can be configured to operate in a Constraint Find mode. In Constraint Find mode, the device can collect data from some or all of the instrumentation for processing and subsequent identification of constraints. Alternatively or additionally, the device can be configured to operate in a Flow Assurance mode. In Flow Assurance mode, the device can only analyze input values ​​(e.g., pressure, flow rate, etc.). As described above, the apparatus comprises a blower configured to couple to the water sprinkler system. The device can be connected to the system by any suitable means. In certain configurations, the device can be connected via one or more of the following: a conduit CQQfren / eznz / q / Y IVIA / drainage, a slot clamp type fastening element, or by permanent modification to the sprinkler system. The blower can be configured to admit air at atmospheric pressure and provide exhaust air to the water sprinkler system at a higher air pressure than atmospheric pressure. For example, but not exclusively, the blower can be configured to provide exhaust air at a maximum gauge pressure of 0.7 bar and a flow rate of 0 ft³ / min to 1000 ft³ / min (or 0.47 m³ / s). Beneficially, the blower is able to direct an airflow at a high flow rate and a relatively low gauge pressure, i.e., a pressure higher than atmospheric pressure but lower than high-pressure air systems, into and through the water sprinkler system, and thus avoids or at least reduces the requirement for a gas source such as an accumulator, an air receiver such as a compressed air cylinder bank and / or a pressure regulator skid. The blower can have a relatively small footprint and / or be relatively lightweight. For example, but not exclusively, the blower might occupy a space of approximately 2m by approximately 2m and have a mass of less than 1500 kg. This is particularly advantageous. IVIA / in offshore installations, such as platforms, platforms and the like, due to size and weight limitations for transport to / from the installation and / or where deck space is typically limited and which may prevent conventional test equipment from being installed on a permanent basis. The blower may include a pump. The pump may be a single-stage pump. However, in particular embodiments, the pump is a multi-stage pump, i.e., it has a plurality of impeller stages. For example, the pump may be a four-stage multi-stage pump. Alternatively, the pump may be an eight-stage multi-stage pump. However, it is recognized that the pump may be any suitable number of stages. The pump may be a centrifugal pump. In particular embodiments, the blower is a multi-stage centrifugal pump.Advantageously, the multistage centrifugal pump provides a blower capable of directing airflow at a high flow rate and relatively low gauge pressure—that is, a pressure higher than atmospheric pressure—into and through the water sprinkler system, thus eliminating or at least reducing the need for a gas source such as an accumulator or an air receiver such as an air cylinder bank. IVIA / compressed and / or a pressure regulator skid. This is particularly beneficial in offshore installations, such as platforms, platforms and the like, due to size and weight limitations for transport to / from the installation and / or where deck space is typically limited and may prevent conventional test equipment from being installed on a permanent basis. The blower may include a motor. The motor may be coupled to the pump. The motor may be configured to drive the pump. The motor may be directly coupled to the pump. Alternatively, the motor may be indirectly coupled to the pump, for example, via a transmission system. The transmission system may include, for example, a gearbox, a belt drive, or another suitable transmission system. As described above, the blower is configured to attach to the water sprinkler system. The blower can be configured to connect to a valve (inlet valve) attached to or part of the water sprinkler system. The inlet valve can be configured to control the flow of air between the appliance and the water sprinkler system. The valve may include a non-return arrangement. IVIA / In use, the non-return arrangement can prevent backflow of air from the water sprinkler system. The blower can be configured to connect to the water sprinkler system, for example, the inlet valve, via a fluid conduit. The fluid conduit may consist of or take the form of a hose. Alternatively, the blower can be coupled directly to the water sprinkler system, for example, the inlet valve. The device may include a connector arrangement for directly attaching the blower to the water sprinkler system. The blower may comprise or take the form of an electric blower. Advantageously, providing an electrically powered blower allows the appliance to be connected to the electrical supply of the facility containing the water sprinkler system, thus avoiding the site footprint and transportation requirements associated with a dedicated power supply, such as a generator. However, it will be understood that in some cases the device may include a dedicated power supply, such as a generator. The blower may comprise, be coupled to, or be operatively associated with a variable frequency drive (VFD). Advantageously, the drive of IVIA / variable frequency allows fine control over the pressure or flow rate supplied from the blower. The blower may comprise, or be housed within, an enclosure. Therefore, the device can be used in hazardous environments where, for example, gases, vapors, mists, and dust can form an explosive atmosphere with air. The device can be configured to control the humidity of the air supply. The device can be configured to match the humidity of the air supply to the water sprinkler system when the test is performed at a reference humidity. The reference humidity can be the humidity of the air in the sprinkler system when the sprinkler system has been started or is known to be free of obstructions. The device may comprise an air conditioner configured to control the humidity of the air supply. The unit may include a moisture filter. The moisture filter may be provided at a blower inlet. Advantageously, the provision of a moisture filter allows for control of the humidity of the air supply to the unit. The device, in particular the processing system, can be configured to evaluate any errors that may occur. IVIA / can be induced by humidity and can indicate (if required) the minimum humidity level reduction required at the inlet that the blower can then provide. The device can be configured to determine the probability of condensation of the air blown into the sprinkler system. This can be achieved through mathematical processing of measured values, which may include atmospheric humidity, temperature, and pressure at multiple locations (which may be at the sensor location(s) in the sprinkler system). As described above, the apparatus comprises a sensor arrangement coupled or operatively associated with one or more water sprinkler system outlets, the sensor arrangement being configured to measure the air pressure at the one or more water sprinkler system outlets and to output one or more output signals indicative of the air pressure at the one or more outlets. The sensor arrangement may comprise a sensor configured to be coupled or operatively associated with an outlet of the water sprinkler system. The sensor arrangement comprises a plurality of sensors. At least one of the sensors can be coupled or operatively associated with a system output of IVIA / water sprinklers. The sensor arrangement may comprise sensors coupled or operatively associated with a subset of the water sprinkler system outlets. Alternatively, the sensor arrangement may comprise sensors coupled or operatively associated with all water sprinkler system outlets. The sensor arrangement coupled to, or operatively associated with, one or more water sprinkler system outlets can be configured to measure the air temperature at one or more of the outlets. The sensor arrangement may comprise one or more temperature sensors. At least one of the sensors can be configured to be removable and attached to the water sprinkler system. The sensor may include a connector for connecting the sensor to the associated output. The connector may include a threaded connector, a bayonet-type connector, or another suitable removable connector. At least one of the sensors can be configured to permanently attach to the water sprinkler system. The sensor can be integrally formed or coupled to the associated output. IVIA / The sensor can be attached to the associated output, for example, using an adhesive. The sensor may include a battery, which may be a rechargeable battery. The sensor may comprise a sensor control module. The sensor control module can monitor the sensor's status. For example, the sensor control module can control whether the sensor should be in an awake state or a sleep state. As described above, the sensor arrangement is configured to measure air pressure at one or more outlets of the water sprinkler system. The sensor arrangement may comprise one or more pressure sensors. The sensor arrangement may comprise at least one sensor coupled or operatively associated with the sprinkler system inlet. The sensor arrangement may comprise one or more sensors configured to measure the airflow at the inlet valve. The one or more sensors may comprise or take the form of a flow meter. The sensor arrangement may comprise one or more sensors configured to measure air pressure in the IVIA / inlet valve. The sensor may comprise or take the form of a pressure sensor. The sensor coupled to or operatively associated with the input can be configured to measure temperature. The sensor may comprise a temperature sensor. In use, at the upstream inlet end, one or more sensors configured to measure airflow rate can be used to measure either or both of the volumetric and / or mass flow rate. At the downstream end, by fitting an additional flow device, the pressure sensor measurement can be used to derive the equivalent flow rate at the outlets. The apparatus may include a filter arrangement. For example, the apparatus may include one or more particle filters. At least one, and in certain modes all sensors can be temperature compensated, so that there is therefore no minimum or minimal measurement error as a result of variations in ambient temperature. As described above, the apparatus comprises a communication arrangement configured to carry one or more output signals from the sensor arrangement to the processing system. The communication arrangement may include a communication module. The communication module may be part of the sensor, coupled to the sensor, or operationally associated with the sensor of the sensor arrangement. In certain configurations, the communications module includes a wireless communications module. This module can be configured to communicate via cellular, Wi-Fi, Bluetooth, ZigBee, NEC, IR, satellite, other internet-enabled networks, and / or similar technologies. Alternatively or additionally, the communications module may comprise a wired communications module. The communications module may be configured to communicate via Ethernet or other wired network connections, via a telecommunications network such as FOTS, PSTN, DSL, ADSL, optical carrier line and / or ISDN link or network and / or similar, via the cloud and / or via the Internet, or another suitable data carrier network. The communications module can be configured to communicate via optical communications such as optical wireless communications (OWC), optical free space communications or Li-Fi or via optical fibers and / or similar. The communication arrangement may comprise a receiver configured to receive the output signal from the IVIA / sensor arrangement. The communication arrangement may comprise a transmitter configured to transmit commands to the sensor arrangement, for example, to the sensor control module. The communication arrangement may comprise a transceiver. The communication arrangement may include a communication module. The communication module may be part of the sensor, coupled to the sensor, or operationally associated with the sensor at the inlet valve. In certain configurations, the communications module includes a wireless communications module. This module can be configured to communicate via cellular, Wi-Fi, Bluetooth, ZigBee, NEC, IR, satellite, other internet-enabled networks, and / or similar technologies. Alternatively or additionally, the communications module may comprise a wired communications module. The communications module may be configured to communicate via Ethernet or other wired network or connections, via a telecommunications network such as POTS, PSTN, DSL, ADSL, optical carrier line and / or ISDN link or network and / or similar, via the cloud and / or via the Internet, or another suitable data carrier network. IVIA / The communications module can be configured to communicate via optical communications such as optical wireless communications (OWC), optical free space communications or Li-Fi or via optical fibers and / or similar. The sensor in the inlet valve may comprise a receiver. The sensor in the inlet valve may comprise a transmitter. The sensor in the inlet valve may comprise a transceiver. The communication arrangement may include a receiver configured to receive the output signal from the sensor on the inlet valve. The communication arrangement may include a transmitter configured to transmit commands to the sensor on the inlet valve, for example, to the sensor control module. The communication arrangement may include a transceiver. The apparatus may comprise, be coupled to, or be operatively associated with a data acquisition device. The data acquisition device may be attached to, or communicate with, the sensor array wirelessly. The data acquisition device may be configured to communicate via a cellular, Wi-Fi, Bluetooth, ZigBee, NFC, IR, satellite, or other networks that allow IVIA / Internet and / or similar. Alternatively or additionally, the data acquisition device may communicate via Ethernet or other wired network or connections, via a telecommunications network such as FOTS, PSTN, DSL, ADSL, optical carrier line and / or ISDN link or network and / or similar, via the cloud and / or via the Internet, or other suitable data carrier network. The data acquisition device can be configured to communicate via optical communications such as optical wireless communications (OWC), optical free space communications or Li-Fi or via optical fibers and / or similar. The data acquisition device can be connected to and / or communicate with a control room console at the facility. The communication setup is configured to transmit the output signal to a data acquisition device. Alternatively or additionally, the data acquisition device can be connected to and / or communicate with a remote facility. Alternatively or additionally, the data acquisition device can be connected to and / or communicate with a mobile device, such as a phone, tablet, or similar device. The device can understand, or can communicate with a MA. control system. The control system can determine the condition of the water sprinkler system from the sensor output signals. The control system may be part of the data acquisition device, or it may comprise a separate system located on-site, at a remote facility, and / or it may be a cloud-based system. The control system can be configured to control the operation of the inlet valve. Benefitingly, automatic control of the inlet valve eliminates the need for manual operation, which can lead to inaccuracies in test results. The control system can be configured to control the operation of the sprinkler valve. The processing system can be part of the control system. The apparatus may comprise instrumentation configured to measure one or more of: blower speed, atmospheric temperature, pressure, humidity, temperature, humidity and pressure on the blower inlet side, temperature, pressure and humidity on the blower outlet side, flow rate on the blower outlet side which may be volumetric and mass flow rate; the blower rate may also be used to derive volumetric flow rate and / or mass flow rate. IVIA / Multiple redundancy of instrumentation may be provided. For example, the apparatus may comprise a plurality of instruments for measuring at least one of the above properties of the apparatus. The instruments for measuring at least one of the above properties of the apparatus may be located in one or more locations, and in particular in each location where instrumentation is provided. The device can be configured to record data from the described instrumentation at a fixed air flow rate or air pressure at a variable flow rate or pressure. An example of the latter would be a device that records instrumentation data as the flow rate varies continuously between a lower and an upper limit. This can be applied equally to one or both tests of a new, unrestricted system or a system that may be restricted. The device can be configured to provide pressure zoning. For example, this may involve analyzing a section of the sprinkler system by analyzing test results where the pressure at an upstream location is compared to the pressure at the same location for the sprinkler system when it was unrestricted / uncleaned. Beneficially, this pressure zoning simplifies the analysis of sprinkler system testing. IVIA / water. The sensor arrangement may comprise one or more sensors located at the junctions or intersections of the water sprinkler system's pipe network. This can facilitate the pressure zoning described above. According to a second aspect, a water sprinkler system comprising the apparatus of the first aspect is provided. The water sprinkler system comprises a dry side and a wet side separated by a sprinkler valve, the dry side of the water sprinkler system having a network of pipes and outlets that are kept in an open condition. The water sprinkler system may comprise a plurality of outlets. The outlet or outlets of the water sprinkler system may comprise or take the form of nozzles. According to a third aspect, an installation is provided comprising the water sprinkler system of the second aspect. According to a fourth aspect, a method is provided for testing a water sprinkler system, comprising: To provide a supply of pressurized air through a water sprinkler system using a blower IVIA / coupled to the water sprinkler system; measure the air pressure at one or more outlets of the water sprinkler system and output an output signal indicative of the air pressure at the one or more outlets; transport the output signal to a processing system configured to determine from said one or more output signals the flow rate of the air supply at the one or more outlets. The method may involve determining a condition of the water sprinkler system from the output signals of the outlets. The method may include measuring the airflow rate at an inlet, for example, an inlet valve, of the water sprinkler system. The method may include outputting a signal indicative of the airflow rate at the inlet. The method may include transmitting the output signal to the processing system. The method may involve comparing the output signal indicative of the airflow rate at the inlet with the output signal(s) from the outlets. The method may involve determining a condition of the water sprinkler system from the output signals compared from the input and outputs. The method may involve determining a condition of the IVIA / water sprinkler system by comparing the determined airflow rate at one or more outlets with a reference signal. The reference signal can take the form of the airflow rate in the sprinkler system when the sprinkler system has been started or is known to be free of obstructions. The method may comprise attaching the apparatus described in the first aspect to the water sprinkler system. For example, the method may comprise attaching the blower to the dry side of the water sprinkler system. The method may involve attaching the sensor arrangement to the water sprinkler system. The method may involve attaching sensors to a selected subset of the water sprinkler system outlets. The method may involve recording or registering the subset of locations. The trial period can range from 5 seconds to 120 seconds. For example, the trial period can range from 15 seconds to 60 seconds. In certain modes, the trial period may be 30 seconds. The method may involve comparing the test results with a previous wet test. The method may include the subsequent performance of a wet test. IVIA / The method may involve comparing the test results with the subsequent wet test. According to a fifth aspect, a method is provided, comprising: Perform the fourth aspect test method in a first period of time to provide a first set of test data indicative of the condition of the water sprinkler system; Perform the fourth aspect test method or a wet test at a second time period to provide a second set of test data indicative of the condition of the water sprinkler system; and output the first set of data and the second set of data. The method may involve comparing the first set of data and the second set of data to determine the condition of the water sprinkler system. Beneficially, the method allows monitoring the status of the water sprinkler system. According to a sixth aspect, an apparatus for testing a fire suppression system is provided. The fire suppression system may comprise or take the form of a nitrogen fire suppression system. The apparatus may comprise a blower configured IVIA / for connection to a fire suppression system inlet. The blower can be configured to provide a supply of pressurized gas, for example, air, through the fire suppression system from the inlet to one or more fire suppression system outlets. The apparatus may comprise, be coupled to, or be operatively associated with a gas source. The gas source may comprise a high-pressure gas source, such as one or more compressed gas cylinders. The apparatus may include a regulator. The regulator may be configured to reduce the gas pressure to the operating pressure of the fire suppression system. The device may comprise a sensor arrangement. The sensor arrangement may comprise one or more sensors configured to measure the gas flow at the inlet. The one or more sensors may comprise or take the form of a flow meter. In use, the sensor can be configured to measure the gas flow rate at the operating gas pressure. Beneficially, the device provides flow security for a fire suppression system, for example, a nitrogen fire suppression system, under operating conditions. IVIA / The characteristics of aspects one through five can be used in the apparatus in accordance with aspect six, and vice versa. In accordance with a seventh aspect, a fire extinguishing system comprising the apparatus of the sixth aspect is provided. The fire suppression system may comprise or take the form of a nitrogen fire suppression system. In accordance with an eighth aspect, an installation comprising the fire extinguishing system of the seventh aspect is provided. According to a ninth aspect, a method for testing a fire extinguishing system is provided. The method may comprise providing a supply of pressurized gas, for example air, through a fire extinguishing system using a blower coupled to the fire extinguishing system. The pressurized gas supply can be provided from a gas source. The gas source may comprise a high-pressure gas source, such as one or more compressed gas cylinders. The method may involve reducing the gas pressure, for example, to the operating pressure of the fire suppression system. IVIA / The method may involve measuring the gas flow at the inlet. The characteristics of aspects one through eight can be used in the method according to aspect nine, and vice versa. According to a tenth aspect, a method is provided, comprising: Perform the ninth aspect test method in a first period of time to provide a first set of test data indicative of the condition of the fire extinguishing system; Perform the ninth aspect test method or an inert gas test at a second time period to provide a second set of test data indicative of the condition of the fire extinguishing system; and output the first set of data and the second set of data. According to another aspect, a processing system is provided configured to implement one or more of the above aspects. The processing system may comprise at least one processor. The processing system may comprise and / or be configured to access at least one data store or memory. The data store or memory may IVIA / understand or be configured to receive operating instructions or a program that specifies operations for at least one processor. The at least one processor may be configured to process and implement the operating instructions or program. At least one data storage device may comprise, and / or include, a reader, drive or other media configured to access, optical storage or disk such as a CD or DVD, flash drive, SD device, one or more memory chips such as DRAMs, a network-attached drive (NAD), cloud storage, magnetic storage such as magnetic tape or disk or a hard drive, and / or the like. The processing system may comprise a network or interface module. The network or interface module may be connected to or connected to a network or data carrier connection, which may comprise a wired or wireless network or data carrier connection, such as a data cable, power line data carrier, Wi-Fi, Bluetooth, Zigbee, internet connection, or other similar connection. The network interface may comprise a router, modem, gateway, and / or similar device. The system or processing system may be configured to transmit or otherwise provide the audio signal over the network or interface module, for example, over the internet, intranet, network, or cloud. IVIA / The processing system may comprise one processing device or a plurality of processing devices. Each processing device may comprise at least one processor and optionally a memory or data storage and / or a network or interface module. The plurality of processing devices may communicate through their respective network or interface modules. The plurality of processing devices may form, comprise, or be part of a distributed or server / client-based processing system. According to another aspect, a computer program product is provided configured in such a way that when processed by a suitable processing system it configures the processing system to implement one or more of the above aspects. The software product may be provided on or contained within a carrier medium. The carrier medium may be transient or non-transient. The carrier medium may be tangible or intangible. The carrier medium may comprise a signal, such as an electromagnetic or electronic signal. The carrier medium may comprise a physical medium, such as a disk, a memory card, a memory device, and / or the like. According to another aspect, a carrier medium is provided, the carrier medium comprises a signal, the signal IVIA / when processed by a suitable processing system causes the processing system to implement one or more of the above aspects. Those skilled in the technique will understand that while some methods can implement certain functionality through a computer program containing machine-readable instructions that are executable to carry out the desired operations, the functionality of the computer program could be implemented in hardware (for example, by means of a CPU or one or more ASICs (application-specific integrated circuits)) or by a combination of hardware and software. Although particular pieces of apparatus have been described herein, in alternative embodiments, the functionality of one or more of those pieces of apparatus may be provided by a single unit, processing resource, or other component, or the functionality provided by a single unit may be provided by two or more units or other components in combination. For example, one or more functions of the processing system may be performed by a single processing device, such as a personal computer or the like, or one or more, or each, function may be performed in a distributed manner by a plurality of processing devices, which may be connected locally or IVIA / remotely distributed. The invention is defined by the appended claims. However, for the purposes of this description, it shall be understood that any of the features defined above or described below may be used individually or in combination. For example, the features described above in relation to one of the preceding aspects or below in relation to the detailed description below may be used in any other aspect, or together they may form a new aspect. BRIEF DESCRIPTION OF THE FIGURES These and other aspects will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a schematic view of an apparatus for testing a water sprinkler system; Figure 2 shows an enlarged view of part of the apparatus shown in Figure 1; Figure 3 shows an enlarged view of another part of the apparatus shown in Figure 1; Figures 4, 5 and 6 show a sensor of the sensor arrangement of the apparatus shown in Figure 3; Figure 7 shows an enlarged view of another part of the apparatus shown in Figure 1; IVIA / Figure 8 shows a schematic view of another sensor in the sensor arrangement of the apparatus shown in Figure 1; Figure 9 shows an installation that includes the apparatus shown in Figure 1; Figure 10 shows another installation that includes the apparatus shown in Figure 1; Figure 11 shows a schematic view of an apparatus for testing a fire extinguishing system; Figure 12 shows an enlarged view of part of the apparatus shown in Figure 11. DETAILED DESCRIPTION OF THE INVENTION Referring first to Figure 1 of the accompanying drawings, an apparatus 10 for testing a water sprinkler system 12 is shown. As shown in Figure 1, the water sprinkler system 12 comprises a dry side 14 and a wet side 16 separated by the sprinkler valve 18. The dry side 14 includes a network of pipes 20 and a number of outlets 22, which in the illustrated water sprinkler system 12 take the form of discharge nozzles. With reference now also to Figure 2 of the accompanying drawings, the apparatus 10 comprises a blower 24, a sensor arrangement, generally denoted by 26, and a digital acquisition (DAQ) module 28 that communicates with a control console 30. The control console 30 in turn IVIA / communicates with a console 31 in the control room 32. In the apparatus illustrated 10, the control console 30 is integral to the apparatus 10. However, it is understood that the control console 30 may alternatively be located away from the apparatus 10. Alternatively or in addition to the console 30, the apparatus 10 may comprise a mobile device 33 that communicates with one or more of the control console 30, the control console 31, the sensor array 26, or other components of the apparatus 10. In the apparatus illustrated 10, the mobile device 33 takes the form of a tablet. However, it is recognized that the mobile device 33 may alternatively comprise any suitable mobile device such as a mobile phone or the like. During use, the apparatus 10 may, for example, relay information relating to the sprinkler system 12, the dry-test process, or recommended corrective actions to a user via the mobile device 33.The apparatus 10 further comprises a wireless communication arrangement, which is represented in Figure 1 by arrows 34. In use, and as will be described later, the blower 24 is operable to provide an air supply at a pressure higher than atmospheric pressure to and through the water sprinkler system 12. The sensor arrangement 26 can be operated to measure the air pressure at the outlets 22 of the water sprinkler system 12 and output a signal indicative of the air pressure at the associated outlet 22, which is then wirelessly communicated by the communication arrangement 34 to the data acquisition device 28 via the wireless receiver 36. The data acquisition device 28 communicates with the console 31, in the apparatus illustrated 10, by the optical line 38, although it will be recognized that any suitable means may be used to communicate with the console 31. The ability of Apparatus 10 to perform a water sprinkler system test 12 without requiring a wet test has several significant benefits. For example, Apparatus 10 eliminates the time, expense, and inconvenience involved in preparing for a wet test, such as arranging receptacles to collect the water dispensed from the water sprinkler system 12 and on bagging-sensitive equipment, as well as the time, expense, inconvenience, and inaccuracies involved in performing the wet test. Personnel are also not exposed to the water flow and are therefore not impeded from performing their duties. The ability of Apparatus 10 to perform a water sprinkler system test 12 without requiring a wet test also reduces the risk of corrosion. As shown in Figures 1 and 2, the blower 24 is arranged on a movable skid 40 which has wheels 42 and CQQfren / eznz / q / Y IVIA / is coupled to an inlet valve 42 through a fluid conduit 44. In the illustrated apparatus 10, the blower 24 comprises a pump 46 in the form of a multi-stage centrifugal pump and a motor 48. In use, blower 24 is configured to admit air at atmospheric pressure and provide an exhaust air supply to water sprinkler system 12 at an air pressure higher than atmospheric pressure. Beneficially, the blower 24 is able to direct an airflow at a high flow and a relatively low gauge pressure, i.e., a pressure higher than atmospheric pressure but lower than high-pressure air systems, into and through the water sprinkler system 12, and therefore avoids or at least reduces the requirement for a gas source such as an accumulator, an air receiver such as a compressed air cylinder bank and / or a pressure regulator skid. The Blower 24 occupies a relatively small footprint compared to conventional test equipment. This is particularly beneficial in offshore installations, such as platforms, platforms, and the like, due to size and weight limitations for transport to / from the installation and / or where deck space is typically limited, which may prevent conventional test equipment from being installed on a permanent basis. IVIA / As described above, the apparatus 10 comprises a sensor arrangement 26 operable for measuring the air pressure at the outlets 22 of the water sprinkler system 12 and outputting an output signal indicative of the air pressure at the associated outlet 22. As shown in Figure 1 and referring now also to Figures 3, 4, 5 and 6 of the accompanying drawings, the sensor arrangement 26 comprises a series of sensors 50 coupled to an associated subset of the outlets 22 of the water sprinkler system 12, the sensor arrangement 26 being configured to measure the air pressure at the outlet of the water sprinkler system 12 and to output a signal indicative of the air pressure at the outlet 22 with which the sensor 50 is associated. Although in the illustrated apparatus 10 the sensors 50 are provided in a selected subset of outlets 22, the apparatus 10 may alternatively comprise sensors 50 at each outlet 22. As shown in Figure 4, the sensor 50 comprises a pressure sensor 52, a sensor control module 54, a rechargeable battery 56, and a wireless communications transceiver 58. The pressure sensor 52 is configured to measure the air pressure at outlet 22, which is wirelessly communicated to the data acquisition device 28 by the transceiver 58. IVIA / The sensor control module 54, among other control functions, can determine whether the sensor 50 should be in an on-call or sleep state. The illustrated sensor 50 further comprises a temperature sensor 59 for temperature measurement, and this data can also be transmitted to and used by the device 10 for useful analysis purposes, such as calculating the dew point temperature of the air at the sensor 50. As shown in Figure 1, and referring now also to Figures 7 and 8 of the accompanying drawings, the sensor arrangement 26 further comprises a sensor 60 coupled to the inlet valve 42 of the water sprinkler system 12, the sensor 60 being operable to measure the air pressure in the inlet valve 42 of the water sprinkler system 12 and output an output signal indicative of the air pressure in the inlet valve 42. As shown in Figure 8, the sensor 60 comprises a pressure sensor 62, a sensor control module 64, a rechargeable battery 66, and a wireless communication transceiver 68. The pressure sensor 62 is configured to measure the air pressure at the inlet valve 42 of the water sprinkler system 12 and communicates wirelessly to the data acquisition device 28 via the transceiver 68. The sensor control module 64, among other control functions, can determine whether the sensor should be in an active or sleep state. The illustrated sensor 60 further comprises a temperature sensor 69 for temperature measurement, and this data can also be transmitted to and used by the apparatus 10 for useful analysis purposes, such as calculating the dew point temperature of the air at the sensor 50. Transceivers 58, 68, together with wireless receiver 36 form the communication arrangement 34 of apparatus 10, the communication arrangement 34 configured to carry the output signal indicative of air pressure at outlets 22 and / or inlet valve 42 to the data acquisition device 28. When the test is to be carried out, the blower 24 is activated to provide a supply of air at a pressure higher than atmospheric pressure to and through the dry side 14 of the water sprinkler system 12 for a test period. As the blower 24 in the illustrated apparatus 10 comprises a multi-stage centrifugal pump 24, the blower 24 is capable of supplying air at a high flow rate. Because the air is at a higher pressure than the atmospheric air present within the open dry side 14 of the water sprinkler system 12, the air flows through the network of pipes 20 to the outlets 22 CQQfren / eznz / q / Y where it exits system 12. IVIA / Sensor 60 is configured to measure the air pressure measurement at the inlet valve 42 of the water sprinkler system 12, which is wirelessly communicated to the data acquisition device 28 by transceiver 68. As air exits outlets 22, the air pressure is measured by sensors 50 arranged in the selected subset of outlets 22, although as noted above, in some cases all outlets 22 may be provided with a sensor 50. The transceivers 58 of the sensors 50 are then operable to transmit an output signal to the data acquisition device 28 via the wireless receiver 36, which in turn communicates to the console 30 via the optical line 38. The method may then involve determining the condition of the water sprinkler system 12 from the acquired data. This may involve comparing the data at the inlet valve 42 with the data measured at the outlets 22. Alternatively, or additionally, the air pressure data measured at the outlets 22 may be compared with a previous test using apparatus 10 or with previous wet test data. In this way, the condition of the water sprinkler system can also be monitored over time, either periodically or continuously, in a manner not previously possible. IVIA / As described above, the ability of Apparatus 10 to perform a water sprinkler system test 12 without requiring a wet test has several significant benefits. For example, the apparatus eliminates the time, expense, and inconvenience involved in preparing for a wet test, such as arranging receptacles to collect the water dispensed from the water sprinkler system 12 and on bagging-sensitive equipment, as well as the time, expense, inconvenience, and inaccuracies involved in performing the wet test. Personnel are also not exposed to the water flow and are therefore not impeded from performing their duties. The ability of Apparatus 10 to perform a water sprinkler system test 12 without requiring a wet test also reduces the risk of corrosion in the water sprinkler system 12 and elsewhere in the facility. Furthermore, the apparatus 10 occupies a relatively small footprint in the installation. This is particularly beneficial in offshore oil and gas installations, such as on a platform or rig, where deck space is typically limited and may prevent conventional test equipment from being permanently installed. It will be acknowledged that device 10 can be used in a variety of different installations, but it is particularly IVIA / beneficial in offshore installations. For example, Figures 9 and 10 show installations 100, 100 which include water sprinkler system 12 and apparatus 10 (system 12 and apparatus 10 are of course not shown to scale). In Figure 9, installation 100 takes the form of an offshore platform. In Figure 10, installation 100 takes the form of a tunnel. A sample calculation explaining how the water flow rate can be determined by measuring air pressure is provided below for a simplified system. For incompressible flow, the pressure drop in a pipe is typically given by the Darcy-Weisbach equation. The tests presented here are performed at very low pressures, typically with nozzle outlet pressures of less than 0.1 bar above atmospheric pressure. At these low pressures, the Mach number is very low, for example, less than 0.1. At very low Mach numbers, the air can be said to be in an incompressible flow regime. There is indeed compression, but the difference between using more complex compressible flow calculations and incompressible flow calculations is less than 1% error. Therefore, incompressible flow calculations can be used to simplify the analysis. Consider a simple tube with a nozzle at its end. The pressure loss across this tube is IVIA / calculated by: x ff x L 1 ΔRαβ=---------x - xpx μ2 Where: L = Length of the pipe D = Pipe diameter μ = Fluid velocity p = Fluid density ff = Pipe friction factor To determine the relationship between water pressure loss and air pressure loss constants, xffxL 4 ΔRPLβ=-------x7X p X μ can be eliminated Therefore, it is given ΔΡαβ water _ Pagua - X pagua 2 ΔRaβ air P water'xPair 2 Typically, seawater is used for sprinkler testing, therefore: Pagua = 1027 kg / m3 PAre = 1.225kg / m3 pagua = 6m / sec (typically fire systems are designed to avoid flow velocities greater than 6m / s paire 25m / sec (equivalent air speed for IVIA / dry flow test) Therefore: ΔRaβ water _ ΔRaβ air The following is a simplified demonstration of the comparison between air and water pressure losses. Condition Pressure at A (bar) Pressure loss through pipe (bar) Pressure at B (bar) Initial Wet Test / Hydraulic Simulation (Example values) 2 0.2 1.8 Master Dry Test (Example values) 0.04 0.004 0.036 An initial wet test is performed to commission system 12. During this time, the density application rate is verified and the spray pattern is checked for fit. Typically, the test is performed against the expected outputs from a hydraulic modeling package. IVIA / Once system 12 has been verified and the water pressure losses determined for the pipe network, a dry test is performed using apparatus 10 which then determines the air losses; this is known as the 5 master signature. After a period of time, for example 1 year, an additional dry test is performed using apparatus 10; however, there is now debris built up inside the line (for example, a spurious release swept marine debris 10 into the pipe). With the same inlet pressure, pressure losses are greater due to the restriction within the line, leading to a lower outlet pressure. Condition Pressure at A (bar) Pressure loss through pipe (bar) Pressure at B (bar) Second dry flow test (example values) 0.04 0.028 0.012 The pressure at B for the same inlet pressure at A would now be: PAB water = ~ 50 X PAB Air PAB Water = X 0.012 0.6 bar IVIA / If the nozzle at B had a typical K factor of 25, the flow rate at B during the initial test was: p,™ \ =23γ X min )* íhtros \[ Q I----) = 23vL8 = 30L / min \ min / But now / / z7ros \, Q ---- = 23VÓÍ6 = 17L / mÍn \ min ) Therefore, the above allows the condition of the sprinkler system to be verified. The following describes an example of a test regime that uses the device. In the first application, a wet test and / or inspection of the sprinkler system is carried out to ensure it is in good condition, to determine if the nozzles are seeking the correct pressures, to determine how long it takes the most remote nozzle to reach the desired pressure, to determine if the spray pattern is correct, and to determine if the flow rate in L / m² / min is correct. The drains (not shown) may also be checked to ensure they are functioning properly. The pressure at the inlet and outlet nozzles at which the sensor arrangement 26 of apparatus 10 is measured. Apparatus 10 is operated to remove water by blowing on IVIA / a maximum speed, for example, for 5 minutes to 20 minutes depending on the size of the sprinkler system 12. The blower 24 slowly sweeps through the flow until it reaches maximum pressure. The sensor array 26 monitors the pressure, and the communication array relays the detected pressure data to the processing system, control station, and / or data storage. This forms a master signature for system 12. Apparatus 10 is operable to check for problems in the piping or nozzles by breaking down system 12 into sections. By breaking down system 12 into distinct sections, the apparatus creates a priority list for operators if problems are found, based on the severity of a given restriction. It will be recognized that the inlet pressure recorded during the master signature ramp is a unique property of a clean system. Therefore, if a new signature pressure response is matched to the master signature, then there are no restrictions. The pressure outlet of blower 24 is then reduced so that blower 24 enters the incompressible flow regime. Apparatus 10 is then operated and the flow for the particular test is determined as described above. The airflow requirement for the test IVIA / will change for different systems, however, for an example nozzle system 12, it is estimated that approximately 200 ft3 / min (0.09 m3 / s) of compressed air will be required at 0.25Bar at the nozzles. The pressure loss through the nozzles will be approximately hp.U2 regardless of the fluid (assuming incompressible fluids). Therefore, for the same pressure drop in both fluids, (hp.U2)» » (Ap.U2)awhere w » = water ya» air Therefore Ua / Uw» (1000 / 1.2)½ »29 [U » speed] Therefore Va / V?; » (1000 / 1.2)½ »29 [V » volumetric flow rate] The nozzles are designed for a water flow rate of 285 l / min with a pressure drop of 0.5 bar. This equates to 202 l / min of water with a pressure drop of 0.25 bar, and therefore approximately 5860 l / min of air for a pressure drop of 0.25 bar. 5860 in » 5.86 m3 / min » 200 ft3 / min (0.09 m3 / s) @0.25bar Although this estimate will allow for planning, each system will be fully simulated in software to understand what the expected air pressure at each nozzle will be for a fully compliant system. It will also be recognized that the apparatus described above is merely exemplary and that various modifications may be made without departing from the scope of the IVIA / claimed invention. For example, Figures 11 and 12 of the accompanying drawings show an alternative apparatus 110. Apparatus 110 is similar to apparatus 10 described above, and similar components are represented by similar reference signs increased by 100. Although apparatus 10 has been described above with respect to a water sprinkler system 12, apparatus 110 is configured to perform a flow test and / or assurance on a fire suppression system 112 that uses inert gas fire suppression. The illustrated system 112 takes the form of a nitrogen gas fire suppression system. As shown in Figures 11 and 12, the fire suppression system 112 comprises a network of pipes 120 and several outlets 122, which in the illustrated system 112 take the form of discharge nozzles. The apparatus 110 comprises a blower 124, a sensor arrangement, generally denoted as 126, and a digital acquisition (DAQ) module 128 that communicates with a control console 130. The control console 130, in turn, communicates with a console 131 in the control room 132. In the illustrated apparatus 110, the control console 130 is integral to the apparatus 110. However, it is understood that the control console 130 may alternatively be located away from the apparatus 110. As IVIA / Alternatively or in addition to the console 130, the apparatus 110 may comprise a mobile device 133 that communicates with one or more of the control console 130, the control console 131, the sensor arrangement 126, or other components of the apparatus 110. In the illustrated apparatus 110, the mobile device 133 takes the form of a tablet. However, it is recognized that the mobile device 133 may alternatively comprise any suitable mobile device such as a mobile phone or the like. In use, the apparatus 110 may, for example, relay information relating to system 12, the dry-test process, or recommended corrective actions to a user via the mobile device 133. The apparatus 110 further comprises a wireless communication arrangement, which is represented in Figure 10 by the arrows 134. The communication arrangement 134 communicates with the data acquisition device 128 via the wireless receiver 136. The data acquisition device 128 communicates with the console 131, in the apparatus illustrated 10, by the optical line 138, although it will be recognized that any suitable means may be used to communicate with the console 131. As shown in Figures 11 and 12, the blower 124 is arranged on a movable skid 140 which has wheels 142 and is coupled to an inlet valve 142 through a IVIA / fluid conduit 144. In the illustrated apparatus 110, the blower 124 comprises a pump 146 in the form of a multi-stage centrifugal pump and a motor 148. Apparatus 10 and the methods described above for finding restrictions and / or providing flow assurance are applicable to apparatus 110. However, the equivalent flow calculation (extrapolation of the flow rate for low-pressure gas to high-pressure gas) cannot be used. For this application, another flow assurance test can be performed. This involves connecting apparatus 112 to a high-pressure gas source 170, such as compressed gas cylinders, reducing the gas pressure to the operating pressure of the gas suppression system using a regulator 172, and measuring the gas flow rate at the lower operating gas pressure (by regulation). In this way, final flow assurance under operating conditions for a gas suppression system 112 is provided, supplementary to the method(s) described above.

Claims

1. An apparatus for testing a water sprinkler system having a wet side and a dry side separated by a valve, the apparatus comprising: a blower configured to be coupled to an inlet of the water sprinkler system, the blower configured to provide a supply of pressurized air through the water sprinkler system from the inlet to one or more outlets of the water sprinkler system; a sensor arrangement coupled or operatively associated with one or more of the outlets of the water sprinkler system, the sensor arrangement being configured to measure the air pressure at the one or more outlets of the water sprinkler system and to output one or more output signals indicative of the air pressure at the one or more outlets;and a communication arrangement configured to carry one or more output signals from the sensor arrangement to a processing system configured to determine from said one or more output signals the flow rate of the air supply at one or more outlets.; 2. The apparatus according to claim 1, wherein the apparatus comprises, is coupled to, or is operatively associated with, the processing system.

3. The apparatus according to claim 1 or IVIA / 2, wherein the blower is configured to be coupled to an inlet valve coupled to or forming part of the water sprinkler system.

4. The apparatus according to claim 1, 2 or 3, wherein the blower comprises or takes the form of an electric blower.

5. The apparatus according to any preceding claim, wherein the blower comprises, is coupled to, or is operatively associated with, a variable frequency drive (VED) 6. The apparatus according to any preceding claim, comprising at least one of: an air conditioner configured to control the humidity of the air supply; a humidity filter provided at a blower inlet.

7. The apparatus according to any preceding claim, wherein the sensor arrangement comprises sensors coupled or operatively associated with a subset of the water sprinkler system outlets.

8. The apparatus according to any of claims 1 to 6, wherein the sensor arrangement comprises sensors coupled to or operatively associated with all outlets of the water sprinkler system. IVIA / 9. The apparatus according to any preceding claim, wherein the sensor arrangement comprises one or more temperature sensors coupled or operatively associated with one or more outlets of the water sprinkler system and configured to measure the air temperature at said one or more of the outlets.

10. The apparatus according to any preceding claim, wherein at least one of the sensors of the sensor arrangement is configured to be removably coupled to the water sprinkler system.

11. The apparatus according to any of claims 1 to 9, wherein at least one of the sensors of the sensor arrangement is configured to be permanently coupled to the water sprinkler system.

12. The apparatus according to any preceding claim, wherein the sensor arrangement comprises at least one sensor coupled or operatively associated with the sprinkler system inlet.

13. The apparatus according to claim 12, wherein the arrangement comprises at least one of: one or more sensors configured to measure the air flow at the inlet valve; one or more sensors configured to measure the air pressure at the inlet valve; IVIA / one or more sensors configured to measure the temperature at the inlet valve.

14. A water sprinkler system comprising the apparatus of any preceding claim.

15. A method for testing a water sprinkler system, comprising: providing a pressurized air supply through a water sprinkler system using a blower coupled to the water sprinkler system; measuring the air pressure at one or more outlets of the water sprinkler system and producing an output signal indicative of the air pressure at one or more outlets; and conveying the output signal to a processing system configured to determine from said one or more output signals the flow rate of the air supply at one or more outlets.

16. The method according to claim 15, comprising determining a condition of the water sprinkler system from the output signals of the outlets.

17. The method according to claim 15 or 16, comprising at least one of: measuring the airflow rate at an inlet valve of the water sprinkler system; producing an output signal indicative of the airflow rate at the inlet valve; and transmitting the output signal to the processing system; comparing the output signal indicative of the airflow rate at the inlet with the output signals from the outlets; and determining a condition of the water sprinkler system by comparing the determined airflow rate at one or more outlets with a reference signal.

18. The method according to claim 15, 16 or 17, comprising at least one of: comparing the results of the test method of any of claims 15 to 17 with a prior wet test; subsequently carrying out a wet test and comparing the results of the test method of any of claims 15 to 17 with the subsequent wet test 19. A method, comprising: performing the test method of any of claims 15 to 18 in a first time period to provide a first set of test data indicative of the condition of the water sprinkler system; performing the test method of any of claims 15 to 18 or a wet test in a second time period to provide a second set of IVIA / test data indicative of the condition of the water sprinkler system; and outputting the first set of data and the second set of data.

20. The method may involve making a comparison of the first set of data and the second set of data to determine a condition of the water sprinkler system.

21. An apparatus for testing a fire extinguishing system, the apparatus comprising: a blower configured to be coupled to an inlet of the fire extinguishing system, the blower configured to provide a supply of pressurized gas through the fire extinguishing system from the inlet to one or more outlets of the fire extinguishing system; a sensor arrangement coupled or operatively associated with one or more of the outlets of the fire extinguishing system, the sensor arrangement being configured to measure the gas pressure at the one or more outlets of the water sprinkler system and to output one or more output signals indicative of the gas pressure at one or more outlets;and a communication arrangement configured to carry one or more output signals from the sensor arrangement to a processing system configured to IVIA / determine from said one or more output signals the flow rate of the gas supply at the one or more outlets; 22. The apparatus according to claim 21, wherein the fire suppression system comprises or takes the form of a nitrogen fire suppression system, and the pressurized gas comprises or takes the form of nitrogen gas.

23. A fire extinguishing system comprising the apparatus according to claim 21 or 22.

24. A method for testing a fire extinguishing system, comprising: providing a pressurized gas supply through a fire extinguishing system using a blower coupled to the fire extinguishing system; measuring the pressure of the pressurized gas at one or more outlets of the fire extinguishing system and outputting a signal indicative of the pressurized gas pressure at one or more outlets; and conveying the output signal to a processing system configured to determine from said one or more output signals the flow rate of the pressurized gas supply at one or more outlets.

25. A method comprising: performing the test method according to claim 24, in a first time period to provide a first set of test data indicative of the condition of the fire suppression system; performing the test method according to claim 24 or an inert gas test in a second time period to provide a second set of test data indicative of the condition of the fire suppression system; and outputting the first set of data and the second set of data.