GB2599141A

GB2599141A - Ceiling mountable sensor device

Info

Publication number: GB2599141A
Application number: GB2015242.7A
Authority: GB
Inventors: D Parfitt Anthony
Original assignee: Connected Innovations Ltd
Current assignee: Connected Innovations Ltd
Priority date: 2020-09-25
Filing date: 2020-09-25
Publication date: 2022-03-30
Anticipated expiration: 2040-09-25
Also published as: GB202015242D0; GB2599141B

Abstract

A ceiling mountable sensor device 100 comprises a probe member 103 that extends through a ceiling of a room and into a ceiling cavity above when the sensor device 100 is mounted to the ceiling. The probe member 103 comprises a first sensor 120 for detecting the presence of water within the ceiling cavity. The sensor device 100 further comprises a second sensor 110-b arranged to detect a parameter within the room below the ceiling. The sensor device 100 may monitor for and detect a water leak in a ceiling cavity, and simultaneously monitor for and detect a hazard, for example fire, gas, smoke, carbon monoxide, in a room below the ceiling. The probe member 103 may further comprise a camera 125 and an illumination device 127 to obtain images within the ceiling cavity. The probe member 103 may further comprise a thermal sensor 110-a for detecting temperatures within the ceiling cavity indicative of a fire condition. An alert may be provided locally or remotely. The sensor device 100 may form a mesh network with one or more remote devices.

Description

Intellectual Property Office Application No G1320152427 RTM Date:18 February 2021 The following terms are registered trade marks and should be read as such wherever they occur in this document: Bluetooth Wi-Fi Intellectual Property Office is an operating name of the Patent Office www.gov.uk/ipo

CEILING MOUNTABLE SENSOR DEVICE

BACKGROUND TO THE INVENTION

Water leaks within the home can cause large amounts of damage and, in some instances, pose a threat to life. Leaks into the cavities between the ceiling and floor above are particularly damaging, given that they are difficult to trace and repair and therefore often cause the most damage. Water leaks can be particularly hazardous in combination with an electrical fault, for example. There is a significant threat to life from electrical fires whereby fire can start in wall, ceiling cavity and crawl spaces, where US studies show almost 1 in 10 residential fires start behind walls due to electrical faults and these fires are amongst the most dangerous to life, due to the fact that they spread unseen at the early stages.

One approach to mitigate the hazards posed by water leaks and other hazards is to install a sensor within the household in order to detect the presence of water or other hazard and sound an alarm. However, often by the time the water has been detected, it is too late to completely prevent damage to the building and eliminate the danger to the occupants of the building. Furthermore, if the resident of the household is absent, there is often no way to know what is happening in the household, and it may be weeks before the resident actually finds out about the detected leak and the subsequent damage.

There is therefore a need to improve the detection of water leaks and other hazards at an earlier stage, and preventing or mitigating the effects of the leak 25 once detected.

SUMMARY OF THE INVENTION

In accordance with a first aspect of the present invention there is provided a ceiling mountable sensor device comprising: one or more probe members arranged to extend through the ceiling and into a ceiling cavity above a ceiling when the sensor device is mounted to the ceiling, wherein the one or more probe members comprise one or more first sensors for detecting the presence of water within the ceiling cavity during use; and wherein the sensor device further comprises one or more second sensors arranged to detect a parameter within a room below the ceiling.

In this way, the ceiling mountable sensor device may monitor for and detect a water leak in a ceiling cavity, and simultaneously monitor for and detect a hazard (e.g. fire, gas, smoke, carbon monoxide) in a room below the ceiling. Such simultaneous monitoring of potential hazards in separate areas of a property may advantageously mitigate loss of life and damage to the property. The detection of water within the ceiling cavity is particularly advantageous, since this area of a building is usually out of sight in day to day life, and therefore hazards caused by water or moisture within the ceiling cavity may ordinarily go undetected before substantial damage has been caused. The present invention therefore allows for water leaks and other hazards developing in the ceiling cavity to be accurately identified and monitored to allow the hazard to be addressed and targeted repairs made with much lower cost and disruption than known methods.

The one or more probe members comprise one or more first sensors for detecting the presence or water (including moisture) within the ceiling cavity. As the one or more probe members extend through the ceiling and into the ceiling cavity, this ensures that the first sensor(s) are located within the ceiling cavity when the sensor device is mounted to the ceiling and thereby able to detect the presence of water within the ceiling cavity.

Preferably, the one or more first sensors are arranged to be positioned proximal to (e.g. in contact with, or at the same level as) the floor of the ceiling cavity when the sensor device is mounted to the ceiling. In this way, water within the ceiling cavity (e.g. from a pipe or roof leak) that drips or flows on to the floor of the ceiling cavity (in other words, the lower surface of the ceiling cavity) may be rapidly detected by the one or more first sensors.

The one or more probe members is typically an elongate member that extends upwards (typically substantially vertically) from the ceiling into the ceiling cavity. The first sensor(s) may be arranged so as to extend along the elongate dimension of the probe member so as to maximise the surface area of the sensor, and thereby maximise the sensitivity of water detection. The term "probe member" is used herein to refer to any structure that allows the one or more first sensors to be located within the ceiling cavity when the sensor device is mounted to the ceiling.

The sensor device further comprises one or more second sensors arranged to detect a parameter within a room below the ceiling. Thus, the one or more second sensors are positioned so as to be located below the ceiling when the device is mounted to the ceiling. In other words, the one or more first sensors and the one or more second sensors are arranged so as to be positioned on opposing sides of the ceiling when the sensor device is mounted to the ceiling.

Herein, the term "room" is used to encompass all internal areas within a building which have a ceiling below a ceiling cavity, including hallways, corridors, stairwells etc. The term "ceiling cavity" is used to refer to the space defined "above" the ceiling between the ceiling, walls and roof of the building.

In embodiments, the one or more probe members further comprise: a camera arranged to obtain images within the ceiling cavity during use; and an illumination device for illuminating the ceiling cavity above the ceiling during use. The use of such a camera advantageously allows images of the ceiling cavity to be recorded in order to ascertain the extent of a detected hazard such as a water leak. Such images may be transmitted to a remote device (such as a user smart phone or other smart device) in order that the hazard may be assessed remotely and appropriate action taken so as to minimise disruption and damage to the ceiling.

This is particularly useful if the building residents are not present at the property at the time of the leak. An illumination device (such as one or more LEDs) is provided in order to illuminate the ceiling cavity such that the images may be recorded.

The camera and illumination device may be configured to continuously record images of the ceiling cavity. However, preferably, the camera and illumination device are configured to obtain images and illuminate the ceiling cavity, respectively, in response to the one or more first sensors detecting the presence of water within the ceiling cavity. In this way, the camera and illumination device are only actuated when required, reducing power and data storage requirements.

The one or more first sensors, the camera and the illumination device may be located on separate probe members that each extend into the ceiling cavity.

Typically however, the one or more first sensors, the camera, and the illumination device are located on or integrated with the same probe member. In such embodiments, the ceiling mountable sensor device may comprise a single probe member that comprises each of the one or more first sensors, the camera, and the illumination device.

In embodiments, the one or more probe members may further comprise a thermal sensor for detecting elevated temperatures within the ceiling cavity that are indicative of the presence or risk of a fire. Therefore, in addition to being capable of detecting the presence of a water leak or other hazard within the ceiling cavity, the sensor device of the present invention may simultaneously monitor and detect a fire hazard within the ceiling cavity. For example, the one or more thermal sensors may be able to detect the presence of a flame (due to a local increase in infrared radiation emitted by the flame), or a rise in ambient temperature that is indicative of the presence or risk of a fire. Such a thermal sensor may be located on or integrated with its own respective probe member, or in another example the sensor device may comprise a single probe member that comprises each of the first sensor(s), thermal sensor(s), camera and illumination device.

A thermal sensor, such as an IR thermal sensor, preferably directed into the ceiling cavity, can detect a wall or attic fire which may often go unseen in the early stages. An IR thermal sensor will detect the hazard at a much earlier stage due to the heat being conducted or transported via convection into the ceiling cavity, even if there is little or no smoke escaping into the cavity.

It is envisaged that the one or more probes may comprises further sensors for detecting respective parameters within the ceiling cavity. Examples of such further sensors include a smoke sensor, a gas sensor, and a carbon monoxide sensor.

The ceiling mountable sensor device according to the present invention comprises one or more second sensors arranged to detect a parameter within a room below the ceiling. In general, the one or more second sensors may be configured to detect any parameter. In preferred embodiments, the one or more second sensors comprise a thermal sensor for detecting elevated temperatures within the room below the ceiling that are indicative of the presence or risk of a fire. In the same manner as discussed above with relation to a thermal sensor located within the ceiling cavity, the thermal sensor may detect elevated temperatures as a consequence of increased IR radiation that is emitted from a spark or flame.

The thermal sensor(s) of the sensor device according to the invention may each comprise an infrared detector such as an infrared camera. Preferably, each thermal sensor is an infrared camera comprising an array of thermopile detector pixels. In this way, a highly accurate reading of the temperature of the environment surrounding the sensor may be obtained in order that a fire hazard may be determined. The use of thermal imaging allows for the distribution and change in thermal temperature to be measured, allowing for more information to be gathered so as to provide a more reliable identification of a fire hazard at an earlier stage.

Typically, the thermal sensors comprise a lens providing a field of view of greater than 30 degrees. This advantageously provides a wide field of view, allowing for reliable detection of a fire hazard. Such a wide field of view advantageously allows monitoring of large areas such as the ceiling cavity and the room below the ceiling.

Preferably, the thermal sensors comprise a lens providing a field of view of between 30 and 90 degrees, preferably around 60 degrees.

A preferred thermal sensor that may be used in the sensor device of the present invention is a Panasonic grid-EYE sensor, generally used for movement detection, occupancy detection, people counting and lighting control.

The one or more second sensors may comprise one or more of: a smoke sensor for sensing the presence of smoke in the room below the ceiling during use; a gas sensor for sensing the presence of methane and/or carbon monoxide in the room below the device. The sensor device may comprise an ionisation smoke sensor and/or a photoelectric smoke sensor. The positioning of a smoke and/or gas sensor on the ceiling mountable sensor device advantageously provides accurate detection of such hazards since gas and smoke present within a room typically rises towards the ceiling.

Thus, the ceiling mounted sensor device according to the invention enables simultaneous monitoring and detection of a number of potential hazards in addition to the monitoring and detection of water leaks within a ceiling cavity. The invention therefore makes progress over known devices, where multiple individual devices may be required to detect different hazards, particularly in relation to a ceiling cavity environment which may typically be difficult to access and monitor.

The sensor device preferably comprises an internal battery. In this way, if the mains electricity fails or is switched off (e.g. in response to a detected hazard), the sensor device continues to operate for a certain amount of time.

In embodiments, the one or more probe members may be further configured for mounting the sensor device to the ceiling. For example, the probe member(s) may be integrated with one or more screws for fixing the device to the ceiling. In other embodiments, the one or more probe members are separate to mounting means (e.g. screws) for mounting the sensor device to the ceiling.

Preferably, the sensor device further comprises a processing unit configured to receive data obtained from the one or more first sensors and the one or more second sensors, and determine when the received data is indicative of a hazard. Typically, the data received from the first and second sensors is analysed to determine whether the sensed parameter (e.g. water, temperature, smoke, gas) is greater than a predetermined threshold value that is indicative of a hazard. For example, if the data from the water sensor indicates that the amount of water within the ceiling cavity is greater than a predetermined threshold, or greater than a predetermined rate of flow, then the amount of water within the ceiling cavity is determined to have reached a level deemed to be hazardous.

Each parameter to be sensed by the sensor device may have a corresponding threshold or behaviour that is indicative of the presence of a hazard. The device may include a memory which stores data comprising such threshold values and behaviour change patterns such that the processing unit can compare the sensed data against the corresponding stored data in order to identify the presence of a potential risk. Similarly, the processor can compare the behaviour of a combination of sensed parameters against response data stored in the memory to more reliably identify the presence of a hazard than when based on the output of a single sensor In some examples the sensed parameters are sent for processing at a remote location. For example the parameters may be stored and accessed on a distributed system. The storage and processing of the parameters may take place within the cloud.

The processing unit may be provided locally within the sensor device.

Alternatively, the data analysis may be undertaken by processors in a network in order to reduce the processing power requirements within the sensor device.

In preferred embodiments, the sensor device comprises means to provide an alert to a user. In some embodiments, the sensor device comprises an alarm device, wherein the processing unit is configured to actuate the alarm device in response to determining that the received data is indicative of a hazard. The alarm device may be an audible alarm sounder or visual alarm to notify a user when the processing unit determined that a sensed parameter exceeds a threshold value.

The sensor device may comprise a communications link for transmitting a signal (such as an alert) to one or more remote devices. The communications link may be provided by one or more of: a narrow band radio frequency network, WI-Fi, and Bluetooth. The communications link is preferably configured to transmit a signal to the one or more remote devices to provide an alert of the detected hazard and/or to control one of the said remote devices to take an action to mitigate the detected hazard. The remote device may be adapted to provide an alert of the detected hazard, for example a smart phone, tablet, voice assistant device or other smart user device. For example, a smart phone may run software configured to operate with the sensor device. The software may display alerts to a user, identify the location of an identified hazard, provide details of the identified risk, allow a user to choose an option to address the risk such as shutting off a mains or local supply of gas, water, electricity, activate a sprinkler system, call the fire brigade or turn an appliance off. One or more remote devices may comprise a virtual device, for example a virtual device within the cloud.

The remote device may be adapted to take an action to mitigate the detected hazard. Examples of such remote devices include an isolation unit comprising a remotely controlled valve connected to a mains water or gas supply and operable to shut off the supply on receipt of a signal from the sensor device, a fire alarm, a smoke alarm, and a sprinkler system. Such remote device may take action automatically on receipt of a signal from the sensor device, or may take action in response to a signal received from a user remote device.

The isolation units may take several different forms. In one example, at least one isolation unit comprises a local water isolation unit arranged for installation at the local water connection to an electrical appliance; the local water isolation unit comprising: a cabled or wireless connection for connecting to the electrical safety device; and a motorised valve; wherein the local water isolation unit is configured to close the motorised valve to restrict the water supply to the electrical appliance upon receiving a signal from the ceiling mountable device. In this way, the water supply to a particular appliance, group of appliances or region of a building can be restricted to prevent flooding or an electrical fault, which may present a fire or shock hazard, from happening due to escape of water onto an electrical supply or circuit.

Preferably at least one isolation unit comprises a mains supply isolation unit comprising: at least one motorised valve arranged for installation in a mains water feed, a header water tank or mains gas supply; wherein the mains supply isolation unit is configured to close the motorised valve to restrict the mains supply upon receiving a signal from the ceiling mountable device or a remote device.

Preferably at least one isolation unit comprises a mains electrical isolation unit comprising: a mains electrical shut off switch; wherein the electrical isolation unit is configured to actuate the electrical shut off switch to shut off the mains electricity upon receiving a signal from the electrical safety device. Using these mains isolation units the further supply of gas, electricity or water throughout the building or to a specific zone in a building can be stopped to prevent a hazard escalating.

The main electrical isolation unit may be connected to a mains consumer unit and is configured to actuate a main switch on the mains consumer unit to shut off the main electricity supply. Alternatively the mains electrical isolation unit may be integrated within the consumer unit or fuse box.

The isolation unit may include one or more local sensors to identify a local hazard.

Preferably the isolation unit comprises a processor and one or more of: a thermal sensor; a smoke and/or gas sensor; a carbon monoxide sensor; a moisture and/or water sensor; a current sensor; wherein the isolation unit is configured restrict a flow of water, gas or electricity when the processor determines that a parameter sensed by a local sensor exceeds a predetermined threshold.

In some embodiments, the alert transmitted to a remote device may comprise an image obtained by the camera. For example, in response to the processor detecting that the amount of water sensed within the ceiling cavity exceeds the predetermined threshold, the processor may actuate the camera and illumination device in order to record one or more images of the ceiling cavity. These images may then be transmitted to a remote device such as a smart phone in addition to the notification that the water levels had exceeded the predetermined threshold. In this way, the potential hazard detected within the ceiling cavity may be quickly analysed using the transmitted image(s) with minimal invasive work required, and the appropriate action taken.

The ceiling mountable sensor device according to the invention may be provided as a standalone unit. However, the sensor device provides further advantages when provided as part of a hazard safety system. Accordingly, a second aspect of the present invention provides a hazard safety system comprising: one or more sensor devices as described above in accordance with the first aspect of the invention; and one or more remote devices configured to receive a signal transmitted from the one or more sensor devices.

In this way, the remote device can either alert a user of a potential hazard, or take action to address a potential hazard. As discussed hereinabove, such remote devices may include a sensor device, a smart phone, tablet, voice assistant device or other smart user device, an isolation unit configured to restrict a flow of water, gas or electricity through the isolation unit, a fire alarm, a smoke alarm, and a sprinkler system. One or more remote devices may be virtual devices.

In some examples the remote devices may comprise additional ceiling mountable sensor devices. In particular a further aspect of the invention comprises a plurality of ceiling mountable sensor devices as described in relation to the first aspect, where the ceiling mountable sensor devices are connected together within a network.

The communications link by which the sensor device may communicate with the remote devices typically comprises a wireless communications link, preferably provided by one or more of: a narrow band radio frequency network, Wi-Fi, and Bluetooth. In preferred embodiments, the sensor device and remote devices are in communication by two networks such that if one network goes down, the devices can still communicate in order to provide an alert or automatically perform mitigating actions such as shutting off a mains water supply or sounding an alarm.

Preferably, the one or more sensor devices and one or more of the remote devices form a mesh network in which one or more sensor devices and one or more remote devices can communicate.

In certain preferable examples, the ceiling mountable sensor device provides a local network hub to which one or more remote devices are connected. In some examples the ceiling mountable sensor device and remote devices are connected within a local network and the ceiling mountable device is connected to the internet such that the remote devices can access the internet via the ceiling mountable sensor device. Preferably the ceiling mounted sensor device and the remote devices are connectable to form a mesh network, wherein the ceiling mounted sensor device is additionally connectable to the internet.

In certain preferable embodiments one or more remote devices comprise a sensor device, wherein the sensor devices comprise a sensor for sensing a parameter associated with a hazard and a communications link for sending data relating to the parameter to a remote device. Preferably the sensor devices are configured to send data relating to the parameter to the ceiling mountable sensor device. Preferably the ceiling mountable sensor device is configured to collect data from a plurality of sensor devices. Preferably the ceiling mountable sensor device is configured to send the collected data to a processing unit to determine the presence of a hazard based on the collected data. The processing unit may be a processing unit, within the ceiling mountable sensor device, a local processing unit to which the mountable ceiling device is connected within a local network.

Preferably the ceiling mountable sensor unit comprises an internet connection for uploading the collected data for remote processing, for example in a platform in the cloud.

One or more remote devices may comprise electrical safety devices, for example as described in WO 2020/016570. The electrical safety devices may comprise a sensor configured to sense a parameter, wherein the electrical safety devices further comprise a communications link for sending information on the sensed parameter to the ceiling mounted sensor device. The sensor may preferably comprise a thermal sensor, preferably an IR sensor In some examples one or more remote device comprise an electrical safety device comprising a socket arranged to receive an electrical plug of an electrical appliance to connect a current supply to the electrical appliance; a thermal sensor arranged to detect the surface temperature of an electrical plug when received in the socket, the thermal sensor preferably comprising an infrared camera comprising an array of thermopile detector pixels; and a wireless communications link for communicating with the ceiling mountable sensor device and, preferably, one or more remote devices.

In some examples one or more remote devices comprise an electrical appliance comprising a housing; internal electrical components within the housing configured to provide a function of the electrical appliance; a thermal sensor arranged to detect the surface temperature of the electrical components, the thermal sensor preferably comprising an infrared camera comprising an array of thermopile detector pixels; and a wireless communication link configured to allow communication with the ceiling mountable sensor device and, preferably, one or more remote devices. The electrical appliance may comprise a microwave, a gas or electric oven, a boiler, a consumer unit, a dishwasher, a fridge and/or freezer, a washing machine, a tumble drier or a charger.

In some examples one or remote devices comprise a light switch device comprising: a switch for connecting to electrical circuitry to operate a room light; a first sensor for sensing a parameter within the room; a wireless communications interface for sending a signal to the ceiling mountable sensor device or a remote device. The light switch device preferably comprises a smoke sensor for sensing the presence of smoke in the room. The light switch device preferably comprises a thermal sensor for detecting elevated temperatures in the room, wherein the thermal sensor is preferably an infrared sensor.

In some examples of the invention the light switch device comprises: a probe member arranged to extend through the wall into a wall cavity, the probe member comprising a second sensor for detecting a parameter within the wall cavity during use. The second sensor of the light switch device may comprise one or more of: a smoke sensor for sensing the presence of smoke within the wall cavity; a thermal sensor for detecting elevated temperature within the wall cavity.

In preferable embodiments, the ceiling mountable sensor device and the remote sensor devices are connectable to form a mesh network. The hazard safety system may additionally comprise one or more isolation units configured to restrict a flow of water, gas or electricity through the isolation unit, where the isolation unit are also connectable within the mesh network. The hazard safety system may additionally comprise a user device, for example a smart phone. The user device is preferably connected to the hazard safety system through the internet (through a broadband connection or wirelessly using GPRS). The user device may be connected via the internet to the ceiling mountable sensor unit, which provides a hub within the mesh network. In particular the user device may be connected to a cloud based platform which allows data collected within the hazard safety system to be viewed and further allows the user device to send signals to the hazard safety system to implement actions to control the devices within the hazard safety system Although in the first aspect of the invention described above the one or more first sensors of the ceiling mountable sensor device are configured sensors for detecting the presence of water within the ceiling cavity, with one or more additional optional sensors, in other examples the one or more first sensors may comprise solely a thermal sensor or a thermal sensor in combination with one or more additional sensors.

In particular, in a further aspect there is provided a ceiling mountable sensor device comprising: one or more probe members arranged to extend through the ceiling and into a ceiling cavity above a ceiling when the sensor device is mounted to the ceiling, wherein the one or more probe members comprise one or more first sensors for elevated temperatures within the ceiling cavity that are indicative of the presence or risk of a fire; and wherein the sensor device further comprises one or more second sensors arranged to detect a parameter within a room below the ceiling. In this way, the ceiling mountable sensor can detect the risk of electrical fires starting in the ceiling cavity, which would otherwise go unseen in the early stages.

The ceiling unit of this aspect may comprise any of the features described above in relation to the first aspect of the invention. In particular the thermal sensor may comprise an infrared detector, preferably directed into the ceiling cavity.

Preferably, the thermal sensor comprises an infrared camera comprising an array of thermopile detector pixels. In this way, a highly accurate reading of the temperature of the environment surrounding the sensor may be obtained in order that a fire hazard may be determined. The use of thermal imaging allows for the distribution and change in thermal temperature to be measured, allowing for more information to be gathered so as to provide a more reliable identification of a fire hazard at an earlier stage.

In the case of a wall or attic fire, which may often go unseen in the early stages, an 1k thermal sensor will alert to fire hazard much quicker because it will detect heat build-up, even if the is little or no smoke escaping into the cavity, from the heat escaping up the wall cavity and being conducted or by convection into the ceiling cavity.

In a further aspect of the invention there is provided a light switch device for mounting on a wall of a room, the light switch device comprising: a switch for connecting to electrical circuitry to operate a room light; a first sensor for sensing a parameter within the room; a probe member arranged to extend through the wall into a wall cavity, the probe member comprising a second sensor for detecting a parameter within the wall cavity during use; and a wireless communications interface for sending a signal to a remote device.

The light switch device may comprise any of the features described above in relation to the ceiling mountable sensor device.

The light switch device preferably comprises a smoke sensor for sensing the presence of smoke in the room. The light switch device preferably comprises a thermal sensor for detecting elevated temperatures in the room, wherein the thermal sensor is preferably an infrared sensor. The second sensor of the light switch device may comprise one or more of: a smoke sensor for sensing the presence of smoke within the wall cavity; a thermal sensor for detecting elevated temperature within the wall cavity, a water sensor for detecting the presence of water in the wall cavity.

Preferably the thermal sensor comprises an infrared sensor, for example an infrared camera comprising an array of thermopile detector pixels. Preferably the thermal sensor has a field of view between 30 and 90 degrees, preferably around 60 degrees.

In a further aspect of the invention there is provided a mountable sensor device for mounting to the wall or ceiling of a room, the mountable sensor device comprising one or more probe members arranged to extend through the wall or ceiling and into a cavity behind the wall or ceiling when the sensor device is mounted to the wall or ceiling, wherein the one or more probe members comprise one or more first sensors for detecting a parameter within the ceiling cavity during use; and wherein the sensor device further comprises one or more second sensors arranged to detect a parameter within the room.

The mountable sensor device may have any of the features or functionality described herein with respect to the ceiling mountable sensor device or the light switch device. Preferably the first sensors comprise a thermal sensor, preferably an IR sensor, for detecting the presence of an elevated temperature in the cavity and/or a smoke sensor for detecting the presence of smoke within the cavity.

Preferably the second sensors comprise a thermal sensor, preferably an IR sensor, for detecting the presence of an elevated temperature in the room.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a side view of a ceiling mountable sensor device according to an embodiment of the invention; Figure 2 is a plan view of a ceiling mountable sensor device as seen from the room below the ceiling to which it is mounted; Figure 3 is a schematic diagram illustrating how the ceiling mountable sensor device of the present invention may be fixed to a ceiling; and Figure 4 is a schematic diagram illustrating a hazard safety system according to an aspect of the present invention.

DETAILED DESCRIPTION

Figure 1 is a side view of a ceiling mountable sensor device 100 according to an embodiment of the invention. The device 100 comprises a main body 101 which has a substantially square profile in plan form (see Figure 2), and comprises an upper surface 101b and a lower surface 101a. Here, the term "upper surface" is used to refer to the surface of the main body that is uppermost when the device is fixed to a ceiling, and the term "lower surface" is used to refer to the surface of the main body that is lowermost when the device is fixed to the ceiling. The device 100 further comprises an elongate probe member 103 that extends from an upper surface 101b of the main body.

In this way -and as schematically illustrated in Figure 3 -when the sensor device 100 is mounted to a ceiling 1, the probe member 103 extends through the ceiling 1 and into a ceiling cavity 5 above the ceiling. The ceiling cavity is defined by the upper part of the ceiling 1, the roof 3 of the building, and any building walls. As further shown in Figure 3, when the device 100 is fixed to the ceiling, the lower surface of 101a of the main body is located within the room 7 below the ceiling. The lower surface 101a may sit proud of the ceiling (as shown in Figure 3), or may be positioned flush with the ceiling. The upper surface 101b of the main body may be positioned so as to abut the ceiling (as shown in Figure 3), or the device 100 may be mounted such that the upper surface is within the ceiling structure, or within the ceiling cavity. The sensor device 100 is typically fixed to the ceiling using screws (not shown).

The probe member 103 and the main body 101 are typically integrally connected, although in some embodiments the probe member 103 and the main body 101 may be removably attachable in order to aid mounting of the device to the ceiling.

The probe member 103 in this embodiment has a cylindrical, or "rod" geometry, although other geometries are envisaged such that at least a part of the probe member 103 is located within the ceiling cavity when the device is mounted to the ceiling. Thus, the probe member has a length that is greater than the thickness of the ceiling to which the sensor device is mounted. A typical length of the probe member 103 is 5 mm to 50 mm, preferably 10 mm to 20 mm, preferably around 14 mm.

The probe member 103 comprises a water sensor 120 positioned on the outer surface of the probe member, as shown in Figure 1 and schematically illustrated in Figure 3. The water sensor 103 comprises a plurality of elongate parallel conductor elements whose resistance varies dependent on the level of water in contact with the conductors. The elements of the sensor typically extend along the length of the probe member 103 so as to maximise the surface area of the water sensor within the ceiling cavity.

The water sensor 120 is located at a proximal end of the probe member with respect to the upper surface 101b of the main body. In this way, a part of the water sensor is positioned so as to be in contact with, or at the same level as, the floor 5a of the ceiling cavity (i.e. the upper surface of the ceiling) when the device 100 is fixed to the ceiling. This allows the build-up of water within the ceiling cavity 5 to be quickly detected. In this way, water-based hazards (such as water leaks) occurring within the ceiling cavity may be detected at an early stage, and quickly mitigated in order to avoid substantial damage or even loss of life.

An example of a water sensor that may be used in the present invention is a sensor comprising two electrically conductive probes arranged such that the presence of water between the electrically conductive probes creates a circuit indicating the presence of water.

The probe member 103 further comprises a camera 125 and an illumination device 127 that are each mounted at a distal end of the probe member 103 with respect to the upper surface 101b of the main body 101. In this way, the camera 125 may cover a wide field of view within the ceiling cavity. Upon determination of a water leak by the device 100, the illumination device 127 (here in the form of a plurality of LEDs) is actuated in order to illuminate the ceiling cavity. An image of the ceiling cavity may then be recorded by the camera 125. In the example device illustrated in Figure 1, a single camera 125 is shown. However, a plurality of cameras 125 mounted around the circumference of the probe member 103 may be used in order that an images of substantially the entire ceiling cavity may be obtained in response to a detected water hazard.

The probe member 103 further comprises a plurality of thermal sensors 110-a positioned at a distal end of the probe member 103 with respect to the upper surface 101b of the main body 101. The plurality On this example four) of thermal sensors 100-a are mounted around the circumference of the probe member 103 so as to be configured to detect elevated temperatures from substantially all angles within the ceiling cavity. By detecting the presence of elevated temperatures within the ceiling cavity, a potential fire hazard may be detected at an early stage. Further information on the thermal sensors is provided below.

In the example illustrated in Figure 1, the device 100 comprises a single probe member 103 that comprises each of the water sensor 120, thermal sensors 110a, camera 125 and illumination device 127. This allows for a compact device that may be easily installed. However, in other embodiments, the device may comprise two or more sensor probes, each comprising one or more sensors.

The sensor device 100 of the presently described embodiment further comprises a plurality (in this example four) of thermal sensors 110-b integrated with the lower surface 101a of the main body 101 and arranged to face outwardly away from the lower surface 101a of the device. In this way, when the device 100 is fixed to the ceiling, the thermal sensors may detect the temperature of the room 7 below the ceiling 1. More specifically, the lower surface 101a of the housing comprises a domed portion 112 having a substantially hemispherical geometry, and the thermal sensors are located within laterally spaced recesses within the domed portion.

Therefore the plurality of thermal sensors 100-b in combination provide a wide thermal coverage of the room 7 below the ceiling.

In particular, the thermal sensors 110 are capable of detecting elevated temperatures that are indicative of a spark or flame, and therefore indicative of a potential fire hazard. The thermal sensors 110-a provided on the probe member 103 are the same type of thermal sensor 110-b that are provided on the lower surface 101a of the housing. Each thermal sensor of the device 100 is provided by an infrared sensor, in particular an infrared camera comprising an array of infrared detector pixels. The infrared array sensor may comprise an 8x8 grid array of thermopile elements that detect absolute temperature by measuring the emitted infrared radiation. This infrared array sensor is able to provide thermal images by measuring actual temperature and temperature gradients, allowing highly precise measurements of surface temperature and identification of changes in temperature.

The infrared array sensor preferably also includes a lens to provide an increased viewing angle such that a large area (e.g. of the ceiling cavity or the room below the ceiling) can be imaged. The lens may comprise an integral silicon lens which provides a viewing angle of around 60 degrees. The thermal sensors are preferably configured to detect temperature changes over a range of -20°C to 100°C. This allows for tracking of the temperature distribution within the field of view in the ceiling cavity or room. The thermal sensor 110 may be for example a Panasonic grid-EYE sensor, generally used for movement detection, occupancy detection, people counting and lighting control.

The thermal sensor can be configured to determine when the ambient temperature rises above a threshold, for example 55 degrees Celsius, to determine the presence of a potential hazard. An infrared array sensor also provides for the possibility of more complex processing carried out on the thermal image received by the sensor. For example, machine learning based algorithms can be used to detect temperature change patterns within the field of view which are indicative of a fire or risk of fire.

The main body 101 of the sensor device 100 comprises further sensors that are arranged to detect corresponding parameters in the room 7 below the ceiling.

More specifically, as shown in Figure 2, the sensor device 100 comprises smoke sensors 140a, 140b configured to detect smoke in the vicinity of the device, for example from a fire that has broken out in room 7. Smoke sensor 140a is an ionisation smoke sensor, and smoke sensor 140b is a photoelectric smoke sensor.

The sensor device 100 also comprises a carbon monoxide sensor 150 configured to detect carbon monoxide in the vicinity of the device, for example from gas fires or boilers. The device 100 further comprises a gas sensor 130 for detecting gas in the vicinity of the device.

Each of the sensors of the device 100 (whether located on the probe member 103 so as to detect water and other parameters within the ceiling cavity, or located on the main body 101 so as to detect a parameter in the room 7 below the ceiling) is electrically connected to processing unit 107 within the main body 101, such that the processing unit can determine whether any of the sensed parameters are indicative of a potential hazard. The processing unit 107 is configured to determine the presence of a potential hazard by identifying when the value of a sensed parameter exceeds a predetermined threshold value. For example, in the case of the water sensor 120, the sensed water level within the ceiling cavity may exceed a predetermined value stored in memory, and consequently the processing unit determines the presence of a potential water leak. In such a scenario, the processing unit 107 is further operable to control the illumination device 127 and the camera 125 so as to record an image of the ceiling cavity in response to the determined hazard.

The processing unit 107 may be capable of performing more complex processing operations to identify the presence of a hazard, for example by identifying a rate of change of a sensed parameter or where the sensed parameter change displays a particular behaviour or pattern associated with an increased risk of a hazard.

The processing unit can also be configured to determine the presence of a hazard based on a combination of sensor outputs in order to identify a risk more reliably. For example, the processing unit 107 may use more complex algorithms, such as machine learning based algorithms, which take the output from multiple sensors in order to determine an elevated risk. For example, in a situation where a thermal sensor 110-b reading and a smoke sensor 140a reading from the room below the ceiling are both lower than their corresponding thresholds, the behaviours of the sensor readings in combination may signify a developing hazard which may therefore be detected at an earlier stage than with a single sensor.

In this way, the ceiling mountable sensor device 100 according to the invention is capable of simultaneously monitoring and detecting a water hazard within a ceiling cavity, as well as a potential fire risk or other hazard in the room below the ceiling.

When the processing unit 107 determines the presence of a potential hazard based on the data received from the plurality of sensors, it may actuate internal alarm sounder 105 in order to alert an occupant of the building of the hazard. The internal alarm sounder may have different forms depending on the detected potential hazard. For example, if a water leak is detected based on the data received from the water sensor 120, a different alarm may be sounded compared to if a potential fire hazard is detected based on the data obtained from one or more of the sensors arranged to sense a parameter within the room below the ceiling.

The sensor device 100 is typically powered by a connection to the mains power supply within the building. However, the device further comprises an internal battery 190 such that the device may continue to operate for a certain period of time should the mains power supply fail or be shut off. In particular, the internal battery 190 allows the water sensor and other sensors to continue to obtain data relating to the environment in the vicinity of the device, and to actuate the alarm sounder 105 in the event of a detected hazard, ensuring the safety of the building occupants.

Figure 4 illustrates an example hazard safety system 1000 according to the present invention. The hazard safety system of this example a ceiling mountable sensor device 100as described above, and a plurality of remote devices. In this example the ceiling mountable sensor device 100 acts as a hub for a local network in which the remote devices are connected to the ceiling mountable sensor device 100. Since it is a requirement within safety regulations for homes and buildings to be fitted with a smoke alarm on the ceiling, providing the hub within the ceiling unit 100 provides an efficient system in which the number of required devices is reduced, since it removes the need for a separate hub unit. The remote devices may also be interconnected so that the ceiling mountable sensor device 100 and the remote devices together form a mesh network.

As described in more detail below, the ceiling mountable sensor device 100 may be connected to the internet 400 to allow for uploading of data for processing and remote control of the devices. Preferably the system 1000 comprises a cloud based platform for monitoring and control of the network. Other remote devices in the network may be directly connected to the internet, as well as within the local network, or may connect via the ceiling unit 100.

In this case the hazard safety system 1000 comprises electrical safety devices 401, 402, 403 for example as described in WO 2020/016570. In particular the system 1000 may comprise safety adaptor devices 401 which are configured to be plugged into the mains sockets with electrical appliances then plugged into the socket of the safety adaptor device 401. The safety adaptor device 401 comprises an infrared sensor arranged to provide a contactless measurement of the plug of an electrical device received in the socket of the adaptor device. The system 1000 of this example also includes a mains socket faceplate device 402. As with the adaptor device 401 the mains faceplate device 402 is comprises one or more IR sensors arranged to provide a contactless measurement of a plug received in a socket of the faceplate device 402. The socket devices 401, 402 also comprise a wireless communications link for sending data relating to the sensed temperature to the ceiling unit.

The socket devices 401, 402 may comprise a processor for processing the sensed data to determine the presence of an electrical hazard such that a signal can be sent to the ceiling unit 100 or another remote device such as a user device 500.

More preferably, processing can take place centrally, either in the hub provided in this case by the ceiling unit 100 or remotely by uploading the data to the internet for processing, for example on a cloud hosted platform. In these examples the socket devices 401, 402 are configured to send the collected data to the ceiling unit, the ceiling unit collecting data from each of the remote devices in the network to upload for processing to determine the presence of an electrical hazard on the cloud platform 400. The platform 400 may then send a signal to a remote device, such as a user device 500 to inform a user or communicate with a further remote device, such as an isolation unit 200, to address the hazard.

The system 1000 of this example also includes a further sensor device in the form of a light switch device 403 comprising at least one sensor for sensing a parameter within a room. The at least one sensor preferably comprises a smoke sensor. The incorporation of a smoke sensor within the light switch device 403 ensures the smoke sensor is placed at an optimal position (around the standard height of a light switch of around 1.5m from floor level) to detect smoke. The at least one sensor may additionally or alternatively comprise a thermal sensor as described for the ceiling unit 100. The thermal sensor may be an IR sensor for sensing the ambient temperature in the room in the field of view in front of the light switch.

The connectivity of the light switch sensor may be as described above for the socket sensors 401, 402. In particular, the light switch device is preferably connected with the ceiling mountable device 100 and the other sensor devices within a mesh network and configured to send data on the sensed parameters to the ceiling mountable device 100. The ceiling mountable device is configured to send the data for processing (at a processor within the network or to a processing unit in the cloud 400) to determine the presence of an electrical hazard In other examples the light switch device 403 may have its own local processing unit for processing the data collected within the one or more sensors to determine the presence of a hazard.

The light switch device 403 may also have a similar sensor arrangement as that of the ceiling mountable sensor device 100 shown in Figure 1. In particular the light switch sensor may comprise a a probe member arranged to extend through the wall on which the light switch device is mounted into a wall cavity. The probe member comprises a second sensor for detecting a parameter within the wall cavity during use, in a similar manner to the ceiling unit 100. The second sensor on the probe can include a thermal sensor, preferably an IR sensor, for detecting elevated temperatures within the wall cavity. As explained above, a significant proportion of electrical fires start within the wall and ceiling cavities where they cannot be immediately identified. The light switch sensor 403 with a wall cavity probe therefore allows for elevated temperature indicative of a potential hazard to be detected at an earlier stage. The probe may additionally or alternatively include a smoke sensor for detecting the presence of smoke in the wall cavity which otherwise would not be possible.

As with all sensor devices described herein, the light switch sensor may comprise one or more optional additional sensors such as gas, carbon monoxide, current and/or water/humidity sensor, positioned so as to measure a parameter within a room or extending through the wall to measure the parameter within the wall cavity.

The system 1000 of Figure 4 includes a number of further remote devices, in addition to sensor devices 401, 402, 403. In particular, in this examples the system 1000 also includes an isolation unit 200, and a fire alarm 250. In some arrangements the system may also include multiple ceiling mountable devices 100 fixed to the ceilings in different parts of a building. For example, a first device 100 may be fixed to the ceiling of a kitchen, whereas a second device 100 may be fixed to the ceiling of a hallway. The isolation unit 200 (described in more detail below) is installed in a water supply such as a mains water feed or a header water tank. The fire alarm may be installed within a separate room within the building, such as a bedroom.

Each of the one or more ceiling mountable sensor devices 100 comprises a communications link 109 so as to be able to communicate via wireless connectivity with each of the remote devices, including the sensor devices 401, 402, 403 and also the isolation unit 200 and alarm 250, for example by radio narrow band frequency, Wi-Fi or Bluetooth. Preferably, the sensor devices 100, 401, 402, 403 and other remote devices 200, 250 are configured to communicate over two communications channels such that all of the devices can operate on two different types of network as a failsafe. In this example, the devices can communicate via Wi-Fi 301 and a radio mesh network 303, for example 868MHz. By providing two communications networks, if one network goes down, the device may still be able to communicate with each other.

As explained above, in this preferable example, the mountable ceiling device provides a hub, although in other examples the hub could be provided as a separate unit. The connectivity of each of the devices in the local network may be managed by the hub which is connected to a central router (not shown) within the building. . In Figure 4, the lines connecting devices 401, 402. 403. 500, 200, 250 and the ceiling unit 100 represent a mesh network.

During the course of operation the sensor devices 401, 402, 403, 100 collect data on a sensed parameter using the sensors described above. The data is passed within the mesh network to the hub, in this case provided within the ceiling unit 100. Processing of the data may take place in respective processors of the sensor units, centrally at the hub but most preferably is uploaded to a cloud based platform 400 for processing. A processing unit is configured to analyse the collected data to determine whether the variation in the sensed parameter is indicative of a hazard. The platform is accessible by a user device to monitor data collected by the sensor devices and the current status of all devices within the system 1000. The user can also submit commands via the user device, for example to shut off a particular appliance or to operate an isolation unit to shut off a mains supply.

In particular if the processing unit, provided locally or within the cloud 400, detects the presence of a hazard, for example a water leak in a ceiling cavity determined by the sensor of the mountable ceiling device 100, a signal may be transmitted over the local network 301, 303 to the isolation unit 200, 201. The isolation unit comprises a motorised valve 200 and a wireless receiver 201 configured to receive a signal. In this case, the motorised valve lies in the main supply line, for example a mains water feed or a header water tank. On receipt of a signal received from one of the ceiling mountable sensors devices by the wireless receiver 252, the motorised valve 251 actuates to shut off the water supply. In this way, upon detection of a water leak within the ceiling cavity of the building, further potential damage to the occupants of the building and the building itself may be avoided. This process can be automated or may be confirmed by a user command on a user device once notified by the system.

Similarly, if the processing unit detects a potential fire hazard either in the ceiling cavity or in the room below the ceiling to which the device is mounted based on the sensor data recorded by the mountable ceiling device 100 or one of the sensor devices 401, 402, 403, the sensor device may send a signal over the local network 301, 303 to the fire alarm 250. The fire alarm 250 may thus be actuated in addition to the local alarm 105 located on the sensor device in order to increase the safety of the occupants within the building. As explained above, in the preferable implementation data is collected from the sensor devices 100, 401, 402, 403 at the hub within the mountable ceiling device 100 which then sends the data to a processing unit within the cloud 400. When the processing unit determines the presence of behaviour indicative of a potential risk, it communicates via the hub with the fire alarm 250 and also possibly a user device. The user device may be part of the mesh network, for example when present within the building, or may be contacted directly via an internet connection from the cloud based platform 400.

The local VVi-Fi/mesh network 301, 303 may include one or more further devices that may comprise sensors for hazard detection, or are configured to perform an action in response to a detected hazard. Examples include an electrical appliance with integrated thermal sensor for sending the temperature of the internal electrical components or other such further devices as set out in W02020/016570.

Referring back to Figure 4, the ceiling mountable sensor device 100 may be in communication with one or more remote user devices 500 such as a smart phone or other smart user device. Data obtained from the water sensor and other sensors of the devices 401, 402, 403, 100, 201 may be transferred, via the smart hub 300, to one or more remote user devices 500 via a wireless communication network such as the internet 400. For example, the remote user device may be a smart phone or other smart device that runs software configured to operate with the sensor devices and other remote devices within the network. In particular, the user device may run software in which the data from the system is presented and providing a user interface with which the user can interact to control the various functionality of the system. The system preferably comprises a cloud-based platform 400 in which the data is stored and processed. Alerts and information, such as images collected by the camera of the ceiling mountable sensor unit 100 are preferably sent directly to the user device 500 over an internet connection.

In this way, a user may be alerted as to the detection of a hazard via a notification received on his/her smart phone or other smart device 500. In particular, an image of the ceiling cavity automatically recorded by the camera 125 in response to a detected water hazard may be transmitted to a user's smart device. The image may be analysed by the user in order to determine appropriate next steps.

In addition to displaying alerts to a user, the software may allow a user to choose an option to address the hazard, such as activating the camera 125 or activating the isolation unit 200 by sending a signal to the relevant device via the smart hub 300. These actions are particularly advantageous if the user is not within the building at the time the hazard is detected.

In some embodiments, the data obtained by the sensors of the sensor device(s) may be transmitted to a remote server (e.g. Cloud server) via the smart hub 300 for processing and analysis. This may reduce the computational resources required locally at the sensor device.

Thus, the hazard safety system of the present invention allows a potential water hazard within a ceiling cavity to be identified at an early stage, and appropriate mitigating actions to be taken, such as automatically shutting off a mains water supply and notifying a user. The ceiling mountable sensor device further allows the simultaneous detection of a potential hazard within the room below the ceiling (such as a fire) to be identified and mitigating actions to be taken. In this manner, multiple hazards within a building may be detected at an early stage and appropriate mitigating actions performed in order to minimise building damage and increase the safety of the building occupants.

Claims

CLAIMS1. A ceiling mountable sensor device comprising: one or more probe members arranged to extend through the ceiling and into a ceiling cavity above a ceiling when the sensor device is mounted to the ceiling, 5 wherein the one or more probe members comprise one or more first sensors for detecting the presence of water within the ceiling cavity during use; and wherein the sensor device further comprises one or more second sensors arranged to detect a parameter within a room below the ceiling.
2. The sensor device of claim 1, wherein the one or more first sensors are arranged to be positioned proximal to the floor of the ceiling cavity when the sensor device is mounted to the ceiling.
3. The sensor device of claim 1 or claim 2, wherein the one or more probe members further comprise: a camera arranged to obtain images within the ceiling cavity during use; and an illumination device for illuminating the ceiling cavity above the ceiling during use.
4. The sensor device of claim 3, wherein the camera and illumination device are configured to obtain images and illuminate the ceiling cavity, respectively, in response to the one or more first sensors detecting the presence of water within the ceiling cavity.
5. The sensor device of claim 3 or claim 4, wherein the one or more first sensors, the camera, and the illumination device are located on or integrated with the same probe member.
6. The sensor device of any of the preceding claims, wherein the one or more probe members further comprise a thermal sensor for detecting elevated temperatures within the ceiling cavity that are indicative of the presence or risk of a fire.
7. The sensor device of any of the preceding claims wherein the one or more second sensors comprise a thermal sensor for detecting elevated temperatures with the room below the ceiling that are indicative of the presence or risk of a fire.
8. The sensor device of claim 6 or 7 wherein the thermal sensor comprises an infrared sensor. 10
9. The sensor device of any of the preceding claims, wherein the one or more second sensors comprise one or more of: a smoke sensor for sensing the presence of smoke in the room below the ceiling during use; a gas sensor for sensing the presence of methane, natural gas and/or carbon monoxide in the room below the device.
10. The sensor device of any of the preceding claims, wherein the one or more probe members is further configured for mounting the sensor device to the ceiling.
11. The sensor device of any of the preceding claims, further comprising an internal battery.
12. The sensor device of any of the preceding claims, further comprising a processing unit configured to receive data obtained from the one or more first 25 sensor and the one or more second sensors, and determine when the received data is indicative of a hazard.
13. The sensor device of claim 12, further comprising a communications link for transmitting a signal to one or more remote devices.
14. The sensor device of claim 13, wherein the communications link is configured to transmit a signal to one or more remote devices to provide an alert of the detected hazard and/or to control one of the said remote devices to take an action to mitigate the detected hazard.
15. The sensor device of claim 14 when dependent on claim 3 or claim 4, wherein the alert comprises an image obtained by the camera.
16. The sensor device of any of claims 12 to 15, further comprising an alarm device, wherein the processing unit is configured to actuate the alarm device in response to determining that the received data is indicative of a hazard.
17 A hazard safety system comprising: one or more ceiling mountable sensor devices according to any of claims 13 to 16-and one or more remote devices configured to receive a signal transmitted from 15 the one or more sensor devices.
18. The hazard safety system of claim 17, wherein the communications link comprises a wireless communications link, preferably provided by one or more of: a narrow band radio frequency network, Wi-Fi, and Bluetooth
19. The hazard safety system of claim 17 or claim 18, wherein the one or more sensor devices and one or more of the remote devices form a mesh network in which the one or more sensor devices and one or more remote devices can communicate.
20. The hazard safety system of claim 19 wherein: one or more remote devices comprise a sensor for measuring a parameter associated with a hazard and the one or more remote devices are each configured to send data relating to the parameter to the ceiling mounted sensor device through the mesh network; wherein the ceiling mountable sensor device is connectable to the internet and configured to upload the data received from the remote devices for processing.
21. The hazard safety system of any of claims 17 to 20 wherein one or more remote devices comprise a light switch device, the light switch device comprising: a switch for connecting to electrical circuitry to operate a room light; and a first sensor for sensing a parameter within the room; a wireless communications interface for sending a signal to the ceiling mountable sensor device or a remote device.
22. The hazard safety system of claim 21 wherein the light switch device comprises a smoke sensor for sensing the presence of smoke in the room.
23. The hazard safety system of claim 21 or 22 wherein the light switch device comprises a thermal sensor for detecting elevated temperatures in the room, wherein the thermal sensor is preferably an infrared sensor.
24. The hazard safety system of any of claims 21 to 23 wherein the light switch device comprises: a probe member arranged to extend through the wall into a wall cavity, the probe member comprising a second sensor for detecting a parameter within the wall cavity during use.
25. The hazard safety system of claim 24 wherein the second sensor of the light switch device comprises one or more of: a smoke sensor for sensing the presence of smoke within the wall cavity; a thermal sensor for detecting elevated temperature within the wall cavity.