1 hvacr116 – trade skills testing for co troubleshooting testing for co troubleshooting

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HVACR116 – Trade SkillsHVACR116 – Trade Skills

Testing for COTroubleshooting

Testing for COTroubleshooting

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Test InstrumentsTest Instruments

• Test instruments calibrate either manually or automatically.

• Automatic calibration tells the instrument to calibrate to 0 regardless of CO levels.

• Manual calibration requires the technician to manually press a calibration button.

• TURN OFF AUTOMATIC CALIBRATION!

• Test instruments calibrate either manually or automatically.

• Automatic calibration tells the instrument to calibrate to 0 regardless of CO levels.

• Manual calibration requires the technician to manually press a calibration button.

• TURN OFF AUTOMATIC CALIBRATION!

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Test instrumentsTest instruments

• Should be calibrated per manufacturer’s instructions to a known quantity of CO.

• A False reading of 0 on a CO test instrument is usually caused by high levels of CO outside the building.

• Should be calibrated per manufacturer’s instructions to a known quantity of CO.

• A False reading of 0 on a CO test instrument is usually caused by high levels of CO outside the building.

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Carbon Monoxide AlarmsCarbon Monoxide Alarms

• CO Alarms are warning devices.• Where we place these alarms are determined by

building air movement and duct systems.• Every building that we enter that has external

influences on the combustion system should have a CO Alarm.

• CO Alarms are warning devices.• Where we place these alarms are determined by

building air movement and duct systems.• Every building that we enter that has external

influences on the combustion system should have a CO Alarm.

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Carbon Monoxide AlarmsCarbon Monoxide Alarms

• Any building that uses, or has the presence of Hydrocarbon fuels should have a CO alarm installed.

• However you must be aware that alarms manufactured and sold under the UL 2034 may not provide enough protection of individuals with health problems. You may need a low level alarm.

• Any building that uses, or has the presence of Hydrocarbon fuels should have a CO alarm installed.

• However you must be aware that alarms manufactured and sold under the UL 2034 may not provide enough protection of individuals with health problems. You may need a low level alarm.

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UL2034 StandardUL2034 Standard

• The standard for CO Alarms requires that the alarm sound when the CO levels exceed a set amount for a period of time.

• These times and levels coincide with a 10% COHb when breathed by healthy individuals.

• Remember COHb is the amount of CO in the bloodstream.

• The standard for CO Alarms requires that the alarm sound when the CO levels exceed a set amount for a period of time.

• These times and levels coincide with a 10% COHb when breathed by healthy individuals.

• Remember COHb is the amount of CO in the bloodstream.

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Low Level AlarmsLow Level Alarms

• There are alarms available (and recommended for more sensative individuals) that sound at lower levels of CO. These alarms are not UL listed and are more expensive.

• This is what I would install (and have) in my house.

• There are alarms available (and recommended for more sensative individuals) that sound at lower levels of CO. These alarms are not UL listed and are more expensive.

• This is what I would install (and have) in my house.

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UL2034UL2034

• The standard alarms may not provide adequate protection for children, the elderly, or persons with deteriorated health.

• The standard alarms may not provide adequate protection for children, the elderly, or persons with deteriorated health.

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CO AlarmsCO Alarms

• Realize CO alarms can also have a reading because of several household chemicals and you may have to use a more sensitive test instrument to be sure of an actual problem. (See manual page 29).

• Most test instruments will pick up on hydrogen, such as from a charging battery.

• Realize CO alarms can also have a reading because of several household chemicals and you may have to use a more sensitive test instrument to be sure of an actual problem. (See manual page 29).

• Most test instruments will pick up on hydrogen, such as from a charging battery.

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UL2034 April 30, 1992UL2034 April 30, 1992

CO Level Time

15 ppm 8 hours or

100 ppm No more than 90 minutes or


400 ppm No more than 15 minutes

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UL2034 After Oct. 1995UL2034 After Oct. 1995

CO Level Time

15 ppm No less than 30 days or



400 ppm No more than 15 minutes and

Alarms had to have a reset button that alarmed if 100ppm or more was present for at least 6 minutes.

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UL2034 After Oct. 1, 1998UL2034 After Oct. 1, 1998

CO Level Time

30 ppm No less than 30 days or

70 ppm No less than 60 and no more than 189 minutes or

150 ppm No less than 10 and no more than 50 minutes or

400 ppm No less than 4 and no more than 15 minutes and

Alarms had to have a reset button that alarmed if 70 ppm or more was present for at least 6 minutes.

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UL2034 EffectsUL2034 Effects

• The effect of these changes was to increase the exposure at low levels and cut down on false alarm calls. However, low levels of CO exposure affect non-healthy adults and children the most.

• The lower levels of alarms may have caused false alarms but it did save lives.

• The effect of these changes was to increase the exposure at low levels and cut down on false alarm calls. However, low levels of CO exposure affect non-healthy adults and children the most.

• The lower levels of alarms may have caused false alarms but it did save lives.

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UL2034 EffectsUL2034 Effects

• The most significant update to the UL 2034 listing in October, 1998 was the addition in the instructions stating that individuals with medical problems may consider using a device that provides an audible and visual warning signal for carbon monoxide concentrations under 30ppm.

• The most significant update to the UL 2034 listing in October, 1998 was the addition in the instructions stating that individuals with medical problems may consider using a device that provides an audible and visual warning signal for carbon monoxide concentrations under 30ppm.

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UL 2034 EffectsUL 2034 Effects

• The other effect of the UL 2034 changes was to increase the amounts of other gasses before they cause an alarm condition.

• One of these gasses is Carbon Dioxide.• Carbon dioxide is now allowed up to 5,000 ppm.

• The other effect of the UL 2034 changes was to increase the amounts of other gasses before they cause an alarm condition.

• One of these gasses is Carbon Dioxide.• Carbon dioxide is now allowed up to 5,000 ppm.

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Carbon DioxideCarbon Dioxide

• Carbon Dioxide levels in a building of 2,000 ppm to 4,000 ppm can be harmful to the most healthy individuals.

• Carbon Dioxide levels are most often caused by lack of ventilation and over-sealing buildings for energy efficiency.

• Carbon Dioxide is also measured in PPM.

• Carbon Dioxide levels in a building of 2,000 ppm to 4,000 ppm can be harmful to the most healthy individuals.

• Carbon Dioxide levels are most often caused by lack of ventilation and over-sealing buildings for energy efficiency.

• Carbon Dioxide is also measured in PPM.

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Carbon DioxideCarbon Dioxide

• Excessive CO2 in the air may cause illness symptoms similar to those of CO such as drowsiness, sinus stuffiness, or breathing difficulty.

• These symptoms can be compounded by warmer room temperatures.

• A CO2 and CO measurement upon entering a building can give good safety and IAQ information.

• Excessive CO2 in the air may cause illness symptoms similar to those of CO such as drowsiness, sinus stuffiness, or breathing difficulty.

• These symptoms can be compounded by warmer room temperatures.

• A CO2 and CO measurement upon entering a building can give good safety and IAQ information.

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Carbon Dioxide LevelsCarbon Dioxide Levels

350-450 Normal Outside Levels

< 600 ppm Acceptable Levels

600-1000 Complaints of stiffness and odors

1000 ASHRAE and OSHA standards

1000 - 2500 Increased complaints of drowsiness

2500 - 5000 Adverse health effects

5000 ppm Maximum allowed for 8 hour period

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TestingTesting

• It is important to remember that testing by HVAC/R service personnel on entering EVERY building will reduce the frequency of CO poisoning.

• By documenting potential hazards on service forms helps identify problems and provides a reasonable method of repair and re-inspection.

• It is important to remember that testing by HVAC/R service personnel on entering EVERY building will reduce the frequency of CO poisoning.

• By documenting potential hazards on service forms helps identify problems and provides a reasonable method of repair and re-inspection.

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TestingTesting

• How many technicians enter a home and do not test?

• How many installers do not test?• How many estimators and sales people enter a

home and do not test?

• How many technicians enter a home and do not test?

• How many installers do not test?• How many estimators and sales people enter a

home and do not test?

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Response to a CO CallResponse to a CO Call

• When a consumer calls with a CO call they should be instructed to leave the building.

• Do not have them open doors and windows as this will not allow you to find the problem.

• When a consumer calls with a CO call they should be instructed to leave the building.

• Do not have them open doors and windows as this will not allow you to find the problem.

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• The caller should be instructed to wait outside the building. All others should go to a neighbors house.

• If for some reason the caller and others are not waiting outside the building the first responder must enter the building using a self contained breathing device. SCBA.

• The caller should be instructed to wait outside the building. All others should go to a neighbors house.

• If for some reason the caller and others are not waiting outside the building the first responder must enter the building using a self contained breathing device. SCBA.

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• SCBA are not to be used by untrained personnel.

• Most emergency responders must wear a SCBA if the inside atmosphere is over 35-50 ppm of CO.

• Confusion is one of the symptoms of CO poisoning. Even if caller said everyone is outside look for pets and people again.

• Measure indoor levels and document.

• SCBA are not to be used by untrained personnel.

• Most emergency responders must wear a SCBA if the inside atmosphere is over 35-50 ppm of CO.

• Confusion is one of the symptoms of CO poisoning. Even if caller said everyone is outside look for pets and people again.

• Measure indoor levels and document.

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Response to CO CallsResponse to CO Calls

• A breath test should be administered even if no CO is in the building. The breath test may confirm there was a presence long after it is ventilated.

• A breath test should be administered even if no CO is in the building. The breath test may confirm there was a presence long after it is ventilated.

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Response to CO CallsResponse to CO Calls

• Remember the two circumstances that make CO a hazard are:– A concentration produced that can harm someone.– A way for it to get into the breathable air.

• Remember the two circumstances that make CO a hazard are:– A concentration produced that can harm someone.– A way for it to get into the breathable air.

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Investigation of CO CallsInvestigation of CO Calls

• Once CO presence has been established a thorough investigation of all combustion systems and their interactions within the building must be performed.

• You must find the source prior to allowing the occupants back into the building.

• Once CO presence has been established a thorough investigation of all combustion systems and their interactions within the building must be performed.

• You must find the source prior to allowing the occupants back into the building.

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Safety – yours and your customer’sSafety – yours and your customer’s

Is it safe for me to be working here?

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Understand how your instrument calibrates

Manual verses Automatic

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InvestigationInvestigation

• In warm temperatures CO will rise.• At freezing temperatures CO is heavier than air

and will sink.• It is important to remember that on cold days

outdoor CO levels because of automotive activity are higher than on warm days.

• In warm temperatures CO will rise.• At freezing temperatures CO is heavier than air

and will sink.• It is important to remember that on cold days

outdoor CO levels because of automotive activity are higher than on warm days.

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InvestigationInvestigation

• It is important to know:– What fuel is being used?– How many BTU’s per cubic foot or gallon?

• 1000 cubic foot of natural gas• 140,000 per gallon of oil

– How much is being used?

• It is important to know:– What fuel is being used?– How many BTU’s per cubic foot or gallon?

• 1000 cubic foot of natural gas• 140,000 per gallon of oil

– How much is being used?

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Verify proper combustionVerify proper combustion

• Measure the fuel flow• Verify that combustion air is adequate and to

code.• Verify that systems with vents draft properly and

without interruption.

• Measure the fuel flow• Verify that combustion air is adequate and to

code.• Verify that systems with vents draft properly and

without interruption.

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How much CO is too much?How much CO is too much?

• Many different numbers exist. Always make sure you know what is expected from the Authority Having Jurisdiction.

• Some interesting numbers are:

• Many different numbers exist. Always make sure you know what is expected from the Authority Having Jurisdiction.

• Some interesting numbers are:

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ASHRAEASHRAE

• American Society of Heating, Refrigeration, and Air Conditioning Engineers

• 9 ppm over 24 hours is the maximum exposure.

• American Society of Heating, Refrigeration, and Air Conditioning Engineers

• 9 ppm over 24 hours is the maximum exposure.

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EPAEPA

• Environmental Protection Agency

• 9 ppm over 8 hours.


• 9 ppm over 8 hours.

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Common Action LevelCommon Action Level

• Most often used in the U.S. in most municipalities for further testing

• 9 PPM or more above what is measured outside.

• Most often used in the U.S. in most municipalities for further testing

• 9 PPM or more above what is measured outside.

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BPIBPI

• Building Performance Institute

• 10 to 35 PPM when seen with un-vented appliances. Unacceptable from vented appliances.

• Building Performance Institute

• 10 to 35 PPM when seen with un-vented appliances. Unacceptable from vented appliances.

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ULUL

• Underwriters Laboratory

• 30 ppm for 30 days minimum.

• Underwriters Laboratory

• 30 ppm for 30 days minimum.

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EPAEPA


• 35 PPM for 1 hour


• 35 PPM for 1 hour

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OSHAOSHA

• Occupational Health and Safety Administration

• 50 PPM for workers in an 8 hour day.

• Remember this is for HEALTHY ADULT WORKING MALES.

• Occupational Health and Safety Administration

• 50 PPM for workers in an 8 hour day.

• Remember this is for HEALTHY ADULT WORKING MALES.

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What is too much?What is too much?

• Be safe - 9ppm seems to be the magic number with all we know about CO poisoning and its long term health effects.

• Be safe - 9ppm seems to be the magic number with all we know about CO poisoning and its long term health effects.

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Air Free StandardsAir Free Standards

• The following are standards used to test flue gasses in and Air Free CO test.

• These may also be over-ridden by local codes.

• The following are standards used to test flue gasses in and Air Free CO test.

• These may also be over-ridden by local codes.

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ANSI Z21ANSI Z21

• American National Standards Institute

• 200 PPM CO Air Free is the maximum concentration from an un-vented space heater or a vented water heater.


• 200 PPM CO Air Free is the maximum concentration from an un-vented space heater or a vented water heater.

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ANSI Z21 and EPAANSI Z21 and EPA

• American National Standards Institute• Environmental Protection Agency

• 400 PPM CO Air Free is the maximum concentration allowed in a furnace flue pipe.

• American National Standards Institute• Environmental Protection Agency

• 400 PPM CO Air Free is the maximum concentration allowed in a furnace flue pipe.

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ANSI Z21ANSI Z21


• 800 PPM CO Air Free is the maximum concentration allowed in gas oven emissions


• 800 PPM CO Air Free is the maximum concentration allowed in gas oven emissions

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Air Free MeasurementsAir Free Measurements

• Without measuring the CO and the O2 content of flue gasses there is no way to come up with an “air free” measurement.

• However, roughly 250ppm is 400ppm air free.

• Without measuring the CO and the O2 content of flue gasses there is no way to come up with an “air free” measurement.

• However, roughly 250ppm is 400ppm air free.

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• <100 PPM CO Air Free– Appliance is usually safe and left in operation.

• <150 PPM CO Air Free– Common high level for Gas Oven emission.– Repair if over this amount.

• <100 PPM CO Air Free– Appliance is usually safe and left in operation.

• <150 PPM CO Air Free– Common high level for Gas Oven emission.– Repair if over this amount.

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• 100 - 400 ppm Air Free– Gas ovens, space, water heaters and boilers require

further testing and correction.– Usually left in service with documented time frame for

correction.

• 100 - 400 ppm Air Free– Gas ovens, space, water heaters and boilers require

further testing and correction.– Usually left in service with documented time frame for

correction.

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• > 400 ppm CO Air Free– Appliance taken out of service for replacement or

correction. – This is above ANSI standard for flue gas.– SHUT IT DOWN!!!

• > 400 ppm CO Air Free– Appliance taken out of service for replacement or

correction. – This is above ANSI standard for flue gas.– SHUT IT DOWN!!!

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Flue Gas Sample LocationFlue Gas Sample Location

• Sample flue gas upstream of the draft diverter or regulator but downstream of the furnace breach.

• If problem found a sample can be taken at the outlet of each furnace tube.

• You do not want diluted flue gasses.

• Sample flue gas upstream of the draft diverter or regulator but downstream of the furnace breach.

• If problem found a sample can be taken at the outlet of each furnace tube.

• You do not want diluted flue gasses.

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Test undiluted flue gasesTest undiluted flue gases

51Gas fired ovensGas fired ovens

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Atmospheric Floor FurnaceAtmospheric Floor Furnace

COAD Graphic

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Atmospheric Space HeaterAtmospheric Space Heater

COAD Graphic

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Mobile Home FurnaceMobile Home Furnace

COAD Graphic

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Gas fired, atmospheric, forced airGas fired, atmospheric, forced air

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Gas fired, atmospheric boilersGas fired, atmospheric boilers

58Gas fired hot water tankGas fired hot water tank

64Gas fired, fan assist, forced airGas fired, fan assist, forced air

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Gas fired, high efficiency, forced airGas fired, high efficiency, forced air

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Gas Fired BoilerGas Fired Boiler

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Commercial BoilerCommercial Boiler

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Oil EquipmentOil Equipment

• Take sample at least six inches upstream from the breech side of the barometric control and as close to the boiler breeching as possible.

• Sample hole should be located twice the diameter of the pipe away from any elbows.

• Take sample at least six inches upstream from the breech side of the barometric control and as close to the boiler breeching as possible.

• Sample hole should be located twice the diameter of the pipe away from any elbows.

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Gas EquipmentGas Equipment

• Locate sampling hole on power fired equipment six inches towards the furnace (upstream) from any barometric dampers or draft diverters and as close to the breeching (connection to boiler or furnace as possible).

• On atmospheric equipment take readings inside the port to the draft hood.

• Locate sampling hole on power fired equipment six inches towards the furnace (upstream) from any barometric dampers or draft diverters and as close to the breeching (connection to boiler or furnace as possible).

• On atmospheric equipment take readings inside the port to the draft hood.

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DiagnosticsDiagnosticsCondition CO

PPMCO Action

Flue Temp

FlueDraft

BurnersAffected

FinalAssesMethod

Air Flow100 CFM/ 10000 BTU

Over fired > 100 Stable High Selective Measure

Under fired >100Or 0-10

Stable Low Selective Measure

Venting Rising Rising High Selective Measure

CombustionAir

Rising Rising Low All Measure

Alignment >100 Stable Selective Visual

Dirt / Rust >100 Stable Selective Visual

Mechanical >100 Stable Selective Visual

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DiagnosticsDiagnostics

• We can not do more diagnostics until we talk about combustion and venting.

• We must also talk about combustion testing procedures and proper combustion air supply.

• We can not do more diagnostics until we talk about combustion and venting.

• We must also talk about combustion testing procedures and proper combustion air supply.

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All EquipmentAll Equipment

• Are your measurements within manufacturers specifications?

• Make sure you do not become the designing engineer.

• Are your measurements within manufacturers specifications?

• Make sure you do not become the designing engineer.

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"The significant problems we face cannot be solved by the same level of thinking that created them"

Albert Einstein

1 hvacr116 – trade skills testing for co troubleshooting testing for co troubleshooting

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