GB2294794A - Fuel leak monitoring apparatus - Google Patents

Fuel leak monitoring apparatus Download PDF

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Publication number
GB2294794A
GB2294794A GB9522492A GB9522492A GB2294794A GB 2294794 A GB2294794 A GB 2294794A GB 9522492 A GB9522492 A GB 9522492A GB 9522492 A GB9522492 A GB 9522492A GB 2294794 A GB2294794 A GB 2294794A
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GB
Grant status
Application
Patent type
Prior art keywords
apparatus
gas
fuel
means
sensor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
GB9522492A
Other versions
GB9522492D0 (en )
Inventor
William Michael Sheret
Original Assignee
William Michael Sheret
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date

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Classifications

    • AHUMAN NECESSITIES
    • A62LIFE-SAVING; FIRE-FIGHTING
    • A62CFIRE-FIGHTING
    • A62C2/00Fire prevention or containment
    • A62C2/04Removing or cutting-off the supply of inflammable material
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B21/00Alarms responsive to a single specified undesired or abnormal operating condition and not elsewhere provided for
    • G08B21/02Alarms for ensuring the safety of persons
    • G08B21/12Alarms for ensuring the safety of persons responsive to undesired emission of substances, e.g. pollution alarms
    • G08B21/16Combustible gas alarms

Abstract

Apparatus for monitoring an area for gas leaks includes a fuel gas detector 12 and a carbon monoxide detector 10, a control unit 13 for receiving control signals from the detectors, and a valve control 6 which shuts off the gas supply in the event of a gas leak being detected. The apparatus may include fire detectors 11 and motion detectors 9, [e.g. for detecting earthquakes] and an alarm 14, 15. <IMAGE>

Description

MONITORING APPARATUS This invention relates to a monitoring apparatus which is adapted to detect a hazard and then take steps to reduce or eliminate the hazard. The invention has particular application in relation to the detection and cessation of leaks of fuel and the detection and cessation of leaks of fuel or exhaust gases from domestic or other appliances.

A fuel gas leak within an enclosed area can be very dangerous, and there have been numerous occasions when explosions following gas leaks have resulted in loss of life and extensive damage. Similarly, leakage of exhaust gases, particularly carbon monoxide, from fuel burning appliances has led to numerous deaths and injuries. Such leaks may occur due to a number of reasons, including incorrect appliance or pipework installation, equipment failure or wear, accidental damage or subsidence. In some localities the occurrence of earthquakes may also result in, for example, the fracture of gas supply pipes.

It is among the objects of this invention to provide an apparatus capable of detecting an undesirable leak, or con tions likely to lead to such a leak occurring, and which will respond to the detected condition to minimise further hazard.

Accordingly, in its broadest aspect, the present invention provides apparatus comprising a sensor for detecting at least one of a fuel, gas or exhaust gas leak or a condition likely to lead to the occurrence of such a leak; and means for acting upon such detection to reduce or eliminate further leakage or the risk of such leakage.

In the interest of brevity and ease of understanding, the presence of a gas leak or conditions likely to lead to the occurrence of such leak, including earthquake and fire, may be collectively referred to hereinafter as an "environmental inconsistency".

In a first aspect the present invention provides apparatus comprising a sensor for detecting at least one of a fuel or exhaust gas within an area; and means for shutting off the supply of fuel to that area in the event of such fuel or gas being detected.

In a second aspect the present invention provides apparatus comprising a sensor for detecting earthquake induced motion within an area; and means for shutting off the supply of fuel to that area in the event of such movement being detected.

These aspects may be provided individually or combined in a single apparatus or system.

Preferably, the apparatus includes a plurality of sensors for detecting the presence of different gases and conditions. The sensors may be grouped together or spaced apart. Sensors may be provided at appropriate locations within an area or building, for example adjacent individual appliances, or may be centrally located with sampling intakes positioned at appropriate locations throughout the building and linked to the sensors by conduits.

Preferably also, the means for shutting off the fuel supply includes a valve actuator. Conveniently, the valve actuator operates an existing gas valve or gas cock where the gas supply enters the area or building or where the gas supply enters an existing appliance. This allows the apparatus to be retro-fitted in an existing building without interfering with the existing gas supply pipework.

In many jurisdictions this will permit the system to be fitted by an electrician or other tradesman and does not require the services of an approved or licensed gas fitter.

Alternatively, the means may include a valve to be fitted in a gas supply pipe.

Preferably also, the apparatus includes a control unit for receiving detection signals from the sensors and for producing a control signal to activate the fuel supply shut off means.

Preferably also, the apparatus includes means for producing an alarm signal in response to a detection by a sensor. The alarm means may provide a local alarm to alert building occupants, for example an audible or visual alarm signal, or may transmit an alarm signal to a remote location to alert the emergency services, the gas supplying or distributing utility, or the superintendent of an apartment building in which individual apartments are provided with sensors.

Preferably also, the apparatus includes means for ventilating the area in response to a detection by a sensor. Thus an extractor fan may be switched on or a vent opened on a leak being detected, reducing the risk of explosion in the event of a fuel gas leak, and reducing the risk of poisoning or suffocation in the event of an exhaust gas leak.

These and other aspects of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a schematic representation of a building provided with apparatus in accordance with a first embodiment of the present invention; Figure 2 is a schematic representation of a building provided with apparatus in accordance with a second embodiment of the present invention; and Figures 3, 4, 5 and 6 are schematic representations of aspects of other apparatus in accordance with further embodiments of the present invention.

Reference is first made to Figure 1 of the drawings, whch illustrates a building 1 provided with apparatus in accordance with a first embodiment of the present invention. A weatherproof gas meter box 2 is mounted on an outer wall of the building 1 and includes an inlet from the mains gas supply 3. Within the box 2 there is provided a conventional gas cock 5 and gas meter 4, and a solenoid operated gas valve 6 forming part of the apparatus of the invention. Gas supply pipework 7 leads from the valve 6 to gas appliance, which may be a boiler, cooker, refrigerator or heater. n normal conditions the gas cock 5 and valve 5 are open, allowing flow of gas therethrough.

Four sensors or detectors 9, 10, 11 and 12 are provided within the building 1: a motion detector 9 for sensing movement such as caused by earthquakes or earth tremors; a gas detector 10 for sensing carbon monoxide gas which may be generated by a malfunction in the appliance 8, such as a leak in the exhaust flue; a sensor 11 for detecting heat or smoke or flame, indicating the presence of fire; and a gas detector 12 for sensing the presence of hydrocarbon fuel gas, including the components of the gas supplied to the building 1, as may be caused by a leak in the gas pipe 7 or the appliance 8. Appropriate sensors are readily available from a number of manufacturers, though in this embodiment the individual sensors are contained within a single housing. Each sensor produces an electrical output or control signal on detecting the appropriate stimulus, which signal is transmitted to the input side of a control unit 13, while the output of the control unit 13 is connected to the solenoid operated valve 6. The sensors may be spaced from or housed within the control unit 13.

On receiving a signal from one or more of the sensors 9, 10, 11, 12, the control unit 13 activates the valve 6 to shut off the supply of gas to the pipe 7, thereby, for example, preventing gas within the building 1 reaching an explosive level.

The control unit 13 includes LED displays 18 indicating the status of the sensors 9, 10, 11, 12, a set of green LEDs being illuminated when each sensor is operating correctly and one of a series of red LEDs being illuminated when the respective sensor 9, 10, 11, 12 has produced or is producing control signals. The control unit 13 also includes an appropriate self-test circuit.

In the event of a control signal being generated and the valve 6 closed, the LED display 18 is illuminated on the control unit 13 to show that the valve has been closed and a buzzer in the unit 13 will sound continuously. A reset control is also provided so that the valve 6 will not be opened once closed unless an appropriate reset button 20 is pressed. Resetting the system also silences the buzzer.

This prevents opening of the valve 6 in the event of an environmental inconsistency apparently clearing; for example, gas could clear from the area around the sensor 12 but still remain in localised explodable pockets elsewhere within the building 1. Also, the source of the fault may still exist.

In this example an audible alarm 14 and a visual alarm 15 are provided to indicate that the control unit 13 has received one or more control signals from the sensors. The control unit 13 and alarms 14, 15 may be mounted on a wall of the building 1 and the alarms 14, 15 are remotely sited from the unit 13 for best effect. Also, further alarms may be connected to the unit 13. The audible alarm 14 is arranged to give off a different sound, typically a coded repeating tone, depending on the different environmental inconsistency sensed, and this is of particular assistance t the visually impaired. Similarly, the visual alarm 15 provides a corresponding coded output for each environmental inconsistency and this is of particular assistance to the hard of hearing. The audible alarm 14 runs on a timer but may be silenced at any time by the user.

The sensors 9, 10, 11, 12, the control unit 13 and the alarms 14, 15 are normally powered from the mains electricity supply, through a suitable step down transformer so that all the apparatus thereafter operates at low voltage, typically 12V, but also include an independent power source in the form of rechargeable batteries located within the control unit 13. Accordingly, the apparatus may still operate in the event of the mains electricity supply failing, for example when a power cut occurs or if a fire damages the mains electricity supply.

To minimise the energy requirements of the solenoid valve 6 the valve may be biased into the closed position by a spring, but normally held open by a latch. The valve solenoid thus operates to withdraw the latch on receipt on an appropriate signal from the control unit 13 allowing the spring to close the valve.

Reference is now made to Figure 2 of the drawings which illustrates apparatus in accordance with a second embodiment of the second invention The illustrated apparatus shares many of the features of the apparatus illustrated in Figure 1 and as described above, and common reference numerals have been used to indicate the common features.

Rather than providing an additional gas valve 6 as described above, this embodiment includes an actuator 6a which acts upon the existing gas cock 5 provided within the gas meter box 2. This arrangement simplifies retro-fitting of the apparatus, and does not require any cutting of or interference with the existing gas pipe work 7.

Further, in the embodiment illustrated in Figure 2, the individual remote sensors have been replaced with sample air intakes and filters 10a, lla, linked to the control unit 13a by appropriate conduits 30, 31. The appropriate sensors, including a motion detector 9a, are provided within the control unit 13a, which also includes a fan 32 and exhaust 33.

Reference is now made to Figure 3 of the drawings, which illustrates an apparatus 40 for use in relation to a single main appliance, typically a gas boiler (not shown).

The apparatus 40 includes a sensor housing 41, accommodating sensors 42, 43, 44 for detecting the presence of methane gas, fire, and carbon monoxide, respectively.

The sensor housing 41 is located at an elevated position above the boiler. The sensors 42, 43, 44 are hard wired to an appropriate control unit 45, which is itself linked to an actuator 46 mounted on a gas cock 47 on the pipe 48 used to supply gas to the boiler.

In this application it is expected that there will be traces of carbon monoxide present during normal operation of the appliance, such that the sensitivity of the carbon cnoxie sensor 44 must be adjusted such that it will only react te leveis of carbon monoxide that are higher than expected.

Reference is now made to Figure 4 of the drawings, which illustrates an apparatus 50 for use in relation to a domestic appliance, typically a heating boiler utilising liquid petroleum gas (LPG) as fuel. As in the apparatus 40 described above, the fire and carbon monoxide sensors 51, 52 are located above the appliance, whereas the gas sensor 53 is located below the appliance around 60 cm (2 feet) above the floor. This arrangement reflects the fact that LPG is denser than air.

Reference is now made to Figure 5 of the drawings, which illustrate apparatus 60 in accordance with a further embodiment of the present invention suitable for use in a multi-occupancy building, such as an office block or apartment building. Appropriate detector units 61, 62, 63, 64 are sited within each apartment and are linked to a central control unit 65 located in a public area or in, for example, the building superintendent's office. Each apartment is provided with its own gas valve 66, 67, 68, 69 which is controlled from the central unit 65 according to the inputs received from the detector units.

Reference is now made to Figure 6 of the drawings which illustrates an apparatus 70 intended for use in relation to an oil fired boiler. In this apparatus a single carbon monoxide sensor 71 is provided and connected to an appropriate control unit 72. In this example the control unit is linked to an electrical switch 73 which may be operated to cut off the supply of electricity to the boiler in the event of exhaust gas being detected.

It will be clear that various other forms of sensor or detector as known to those of skill in the art may be provided for use with apparatus in accordance with the present invention. Further, although the above-described embodiments generally illustrate single site sensor groupings or single site monitoring, a single occupancy dwelling may contain two or more of each different sensor, which sensors may be wired in loops. In the assembly illustrated in Figure 2, a number of sampling intakes may be provided and the control unit may be arranged to sample the air inputs from the different sensors simultaneously or sequentially.

The arrangements described above may also be provided with additional functions, for example the control unit may be connected to a telephone line to dial an emergency service in the event of an environmental inconsistency being detected. A burglar alarm could also be included in the device and housed within the same housing as the control unit, but of course activation of the alarm would not be used to close the gas supply. In other embodiments the control unit may operate an extractor fan or vent arrangement to vent gas from a room. The audible alarm 14 described above may be linked to the domestic ring mains to operate one or more acoustic devices at various locations where the devices are plugged into electrical sockets through the building.The control unit or meter box may also include switches to allow the user to electrically open and close the gas cock or valve as desired. If desired the control unit may be interfaced to a computer via an appropriate multi-pin socket.

In addition to the "domestic" applications described above, apparatus in accordance with the invention may be used in industrial applications, for example in workshops where combustible gases are used in metal cutting or welding, such as oxy-acetylene equipment; apparatus may be provided which responds to the presence of acetylene or an unusually high percentage of oxygen in the air. Further as noted in the embodiment illustrated in Figure 6, the invention is not limited to use with gased fired appliances, and may be used in relation to other fuels, such as oil. The apparatus may also be adapted for use with solid fuel appliances and may, for example, operate to cut-off the oxygen supply to such an appliance, and thus extinguish the fuel in the event of carbon monoxide being detected. The invention may also have utility in detecting and stopping leaks of other substances, including refrigerants in buildings having large number of refrigerated units, or in detecting undesirable levels of cleaning compounds as used in commercial dry cleaning operations. Battery powered versions of the apparatus may also be utilised in mobile applications, such as caravans and boats.

It will be evident to those of skill in the art that other modifications and improvements may be made to the described embodiments without departing from the scope of the invention.

Claims (14)

CLAIMS:
1. Apparatus comprising a sensor for detecting at least one of a fuel or exhaust gas within an area; and means for shutting off the supply of fuel to that area in the event of such fuel or gas being detected.
2. The apparatus of claim 1 including a plurality of sensors.
3. The apparatus of claim 2, wherein the sensors are capable of detecting a plurality of conditions including the presence of one or more of fuel, fuel gas, fire, exhaust gas and motion.
4. The apparatus of claim 2 or 3, wherein sensors or groups of sensors are positioned at spaced locations in the monitored area.
5. The apparatus of claim 2 or 3, wherein the sensors are centrally located with sampling intakes positioned at spaced locations in the monitored area and linked to the sensors by conduit.
6. The apparatus of any of the preceding claims wherein the means for shutting off the fuel supply includes a valve actuator.
7. The apparatus of claim 6, wherein the valve actuator operates an existing gas valve where a gas supply enters the area.
8. The apparatus of claim 7, wherein the apparatus includes a control unit for receiving detection signals from the sensor and for producing an activating signal to the fuel supply shut off means.
9. The apparatus of any of the preceding claims wherein the apparatus includes means for producing an alarm signal in response to a detection by the sensor.
10. The apparatus of any of the preceding claims including means for ventilating the monitored area in response to a detection by the sensor.
11. The apparatus of any of the preceding claims wherein sensors are provided for location in individual units within a building and the sensor outputs are linked to a master control unit for activating means for shutting off the gas supply to a respective unit.
12. Apparatus comprising a sensor unit including means for detecting the presence of fuel gas, exhaust gas and fire within a monitored area, and means for shutting off the supply of fuel to that area in the event of a detection by the detection means.
13. Apparatus comprising a sensor for detecting earthquake induced motion within an area; and means for shutting off the supply of fuel to that area in the event of such motion being detected.
14. Apparatus comprising a sensor for detecting at least one of a fuel, gas or exhaust gas leak or a condition likely to lead to the occurrence of such a leak; and means for acting upon such detection to reduce or eliminate further leakage or the risk of such leakage.
GB9522492A 1994-11-02 1995-11-02 Monitoring apparatus Withdrawn GB9522492D0 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB9422059A GB9422059D0 (en) 1994-11-02 1994-11-02 Gas isolating device
GB9515406A GB9515406D0 (en) 1995-07-27 1995-07-27 Gas isolation equipment (sniffer)

Publications (2)

Publication Number Publication Date
GB9522492D0 GB9522492D0 (en) 1996-01-03
GB2294794A true true GB2294794A (en) 1996-05-08

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Family Applications (1)

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GB9522492A Withdrawn GB9522492D0 (en) 1994-11-02 1995-11-02 Monitoring apparatus

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Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2310751A (en) * 1996-02-29 1997-09-03 Cyril William Coleman Safety system with a gas supply cut-off valve
EP0814444A2 (en) * 1996-06-22 1997-12-29 Huberg Gasmesstechnik GmbH Safety device
GB2330438A (en) * 1997-10-14 1999-04-21 Willey Robinson Ltd Gas heating apparatus
GB2346000A (en) * 1999-01-21 2000-07-26 Angus Alexander Ferrier Domestic water and liquid fuel/gasses automatic shut off system
GB2355831A (en) * 1999-08-06 2001-05-02 A Fox Systems Ltd Gas supply leak detection and control
FR2804743A1 (en) * 2000-02-08 2001-08-10 Gennaro Antoine Di Automatic safety valve, fitted to gas meter, for protection against gas leaks, uses gas sensor associated to electro-valve of anti-explosive electro-pneumatic type, fed from very low voltage supply
EP1170710A1 (en) * 2000-07-06 2002-01-09 D'Urania Electrodomesticos Decoration Cocinas S.L. Safety device for combustible gases or liquids
GB2370400A (en) * 2000-08-25 2002-06-26 Pittway Corp Multi-sensor detector having communication means used to control functions associated with detected conditions
WO2005017848A1 (en) * 2003-07-28 2005-02-24 Nazzareno Grimaldi System for the control of a gas plant in a building
US6967582B2 (en) 2002-09-19 2005-11-22 Honeywell International Inc. Detector with ambient photon sensor and other sensors
GB2448372A (en) * 2007-04-14 2008-10-15 Terry Steven Page Carbon monoxide and gas leak detection system activating remote gas supply shut off.
CN104332028A (en) * 2014-11-18 2015-02-04 成都博盛信息技术有限公司 Gas leakage control system
CN104332027A (en) * 2014-11-18 2015-02-04 成都博盛信息技术有限公司 Gas leakage monitoring system
GB2539830A (en) * 2016-09-07 2016-12-28 George Iredale Stephen Safety system

Citations (8)

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Publication number Priority date Publication date Assignee Title
US3955186A (en) * 1974-05-17 1976-05-04 Compugraphic Corporation Character image generation apparatus and CRT phototypesetting system
GB2169732A (en) * 1985-01-16 1986-07-16 Rinnai Kk Safety apparatus for equipment incorporating a flame failure safety circuit
WO1989000682A1 (en) * 1987-07-14 1989-01-26 Dan-Taet, Odense A/S Gas-tightness control system
US4916437A (en) * 1987-08-14 1990-04-10 Gazzaz Hesham H Gas monitoring system with leak detection and flow cutoff
GB2237428A (en) * 1989-10-25 1991-05-01 Johnson & Starley Ltd Fire alarm system
GB2246226A (en) * 1990-07-21 1992-01-22 Stoves Ltd Noxious fluid safety system
EP0511582A1 (en) * 1991-04-29 1992-11-04 EUROGIADA S.r.l. Device for detecting atmospheric impurities
GB2255849A (en) * 1991-05-15 1992-11-18 Alan Smith Gas sensor alarm system

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3955186A (en) * 1974-05-17 1976-05-04 Compugraphic Corporation Character image generation apparatus and CRT phototypesetting system
GB2169732A (en) * 1985-01-16 1986-07-16 Rinnai Kk Safety apparatus for equipment incorporating a flame failure safety circuit
WO1989000682A1 (en) * 1987-07-14 1989-01-26 Dan-Taet, Odense A/S Gas-tightness control system
US4916437A (en) * 1987-08-14 1990-04-10 Gazzaz Hesham H Gas monitoring system with leak detection and flow cutoff
GB2237428A (en) * 1989-10-25 1991-05-01 Johnson & Starley Ltd Fire alarm system
GB2246226A (en) * 1990-07-21 1992-01-22 Stoves Ltd Noxious fluid safety system
EP0511582A1 (en) * 1991-04-29 1992-11-04 EUROGIADA S.r.l. Device for detecting atmospheric impurities
GB2255849A (en) * 1991-05-15 1992-11-18 Alan Smith Gas sensor alarm system

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2310751A (en) * 1996-02-29 1997-09-03 Cyril William Coleman Safety system with a gas supply cut-off valve
EP0814444A2 (en) * 1996-06-22 1997-12-29 Huberg Gasmesstechnik GmbH Safety device
EP0814444A3 (en) * 1996-06-22 1998-09-09 Huberg Gasmesstechnik GmbH Safety device
GB2330438B (en) * 1997-10-14 2000-02-16 Willey Robinson Ltd Gas heating apparatus
GB2330438A (en) * 1997-10-14 1999-04-21 Willey Robinson Ltd Gas heating apparatus
GB2346000A (en) * 1999-01-21 2000-07-26 Angus Alexander Ferrier Domestic water and liquid fuel/gasses automatic shut off system
GB2355831A (en) * 1999-08-06 2001-05-02 A Fox Systems Ltd Gas supply leak detection and control
FR2804743A1 (en) * 2000-02-08 2001-08-10 Gennaro Antoine Di Automatic safety valve, fitted to gas meter, for protection against gas leaks, uses gas sensor associated to electro-valve of anti-explosive electro-pneumatic type, fed from very low voltage supply
EP1170710A1 (en) * 2000-07-06 2002-01-09 D'Urania Electrodomesticos Decoration Cocinas S.L. Safety device for combustible gases or liquids
GB2370400B (en) * 2000-08-25 2004-10-27 Pittway Corp Multi-sensor detector
GB2370400A (en) * 2000-08-25 2002-06-26 Pittway Corp Multi-sensor detector having communication means used to control functions associated with detected conditions
US6967582B2 (en) 2002-09-19 2005-11-22 Honeywell International Inc. Detector with ambient photon sensor and other sensors
WO2005017848A1 (en) * 2003-07-28 2005-02-24 Nazzareno Grimaldi System for the control of a gas plant in a building
GB2448372A (en) * 2007-04-14 2008-10-15 Terry Steven Page Carbon monoxide and gas leak detection system activating remote gas supply shut off.
CN104332028A (en) * 2014-11-18 2015-02-04 成都博盛信息技术有限公司 Gas leakage control system
CN104332027A (en) * 2014-11-18 2015-02-04 成都博盛信息技术有限公司 Gas leakage monitoring system
GB2539830A (en) * 2016-09-07 2016-12-28 George Iredale Stephen Safety system
GB2539830B (en) * 2016-09-07 2017-06-14 George Iredale Stephen Safety system

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WAP Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1)