ES&H Manual

Fire Protection Supplement

 

Chapter 4: Fire Protection System

Inspection, Testing, and Maintenance Procedure

 

 

 

Appendix 4:

Procedure for Testing

Gas Detection Systems

 

 

 

1.0          Purpose

 

This document provides a procedure for conducting periodic testing of a fire-detection device required by NFPA 72 National Fire Alarm Code, 2010 Edition Table 14.4.2.2 Device 14(f) and Table 14.4.5 Component 15(g).

 

2.0          Scope

 

This test is to be performed annually on each gas detection system.

 

3.0          Planning

 

3.1            Notify the facility work coordinator using the approved electronic work control notification procedure.  Allow one week for approval of the requested work and be prepared to reschedule the requested work to satisfy the areas production schedule.

3.2            Staff Required:           2

3.3            Time Required:          4 Hours

3.4            Equipment Required

·       Manufacturer’s Manual (See ‘References’ section below.)

·       Calibrated Thermometer

·       Sensor Sample Cape

·       Pressure Regulator, set to flow 1.5 liters per minute

·       Isolation Valve

·       Approx. 4 feet of ¼-inch I.D. Tygon tubing

·       Calibrated Zero Span Gas

·       Calibrated 50% LEL Methane Span Gas

·       Gas Detector Data Sheet

 

4.0          Test Preparation

 

4.1            Establish the fire-detection system impairment using the Fire Protection Supplemental Chapter 5: Fire Protection System Impairment Procedure for detailed instructions on work planning, advanced notification, and administrative controls.

·       Post the ‘Fire Alarm Systems Testing in Progress’ notification signs.

4.2            Invite the SOTR to witness the test.

4.3            Evacuate hazard area of unnecessary personnel.

4.4            Station a knowledgeable technician at the Fire Alarm Control Panel (FACP); disconnect the building audible alarms at the FACP.  The knowledgeable technician is to remain attentive at the FACP at all times that the audible alarms are disconnected.

·       In the unlikely event that an unanticipated fire alarm signal is received on the FACP, the technician must reconnect the building audible devices and join the building evacuation.

 

5.0          Conduct the Test

 

5.1            Record the detector’s serial number and location on the attached datasheet.

5.2            Make sure the instrument has been operating for a minimum of thirty minutes prior to performing a calibration.

5.3            Determine the ambient temperature in the sensor location.

·       Temperature should be between 50ºF and 90ºF. 

·       Calibration is not accurate at temperatures below 50ºF. 

·       Record the temperature and include it on the calibration certification.

5.4            Calibrate Zero Span.

·       Use sections of the Tygon tubing to make several connections.

·       Connect the outlet on the Zero Span gas valve to the isolation valve.

·       Connect the isolation valve to the high-side of the pressure regulator.

·       Connect the low-side of the pressure regulator to the inlet marked on the sample cape.

5.5            Observe the inlet and outlet designations on the isolation valve.

5.6            Insert the gas sensor into the sample cape, as shown in figure I.

5.7            Fully open the Zero Span gas cylinder valve.

5.8            Fully open the isolation valve.

5.9            Wait approximately 15 seconds and, then, observe the VU meter indication.

·       It is normal for the sensor to show a slight 'zero drift' while in operation.

·       If the indication does not represent true zero, use the zero potentiometer located on the right-hand side of the controller to adjust the zero baseline setting.

·       Record the initial and adjusted readings on the calibration certification.

5.10         Fully close the Zero Span gas cylinder valve.

5.11         Disconnect the calibration tubing assembly from the cylinder outlet.

5.12         Adjust 50% Span.

5.13         Use sections of the Tygon tubing to make several connections.

·       Connect the outlet on the 50% LEL Methane Span gas valve to the isolation valve.

·       Connect the isolation valve to the high-side of the pressure regulator.

·       Connect the low-side of the pressure regulator to the inlet marked on the sample cape.

5.14         Observe the inlet and outlet designations on the isolation valve.

5.15         Check the VU meter.

·       Insert the gas sensor into the sample cape, as shown in figure I

·       Fully open the 50% LEL Methane Span gas cylinder valve.

·       Open the isolation valve.

·       Allow the calibration gas to flow across the sensor for approximately 15 seconds.

·       Observe the VU meter indication.

o   The meter should be stabilized between 47% and 55%.

o   If the reading is no more than 15% outside of the high or low point of this range, adjust the Span potentiometer on the right side of the controller to 50%.

·       Repeat this procedure for each sensor to be tested.

5.16         If the indication is outside of the plus or minus 15% tolerance, or if you are unable to set the Span to 50%, proceed to the troubleshooting section (section VIII) of the instrument operational manual.

5.17         If the sensor is over 18 months old, it likely needs to be replaced. The catalytic bead sensor is an organic device, which deteriorates over its operational life in proportion to its exposure to gasses.

5.18         Fully close the 50% LEL Methane Span gas cylinder valve.

5.19         Disconnect the calibration tubing assembly from the cylinder outlet.

5.20         Replace all sensors to their original locations.

5.21         After successful calibration, affix a current, dated, calibration sticker to the controller housing, and a corresponding color-coded dot to each sensor tested.

5.22         Check high and low alarm settings.

5.23         Operate the high and low alarm setpoint switches to the left of the VU meter and verify alarms.

5.24         Verify the setpoints against the factory settings for the original installation. These settings should be recorded on the controller.

5.25         Record high and low alarm setpoints on the calibration certification.

5.26         Observe the condition of each detector for signs of mechanical damage, or anything that may obstruct the sampling process.

5.27         Document results on the attached data sheet.

 

6.0          System Restoration

 

6.1            Reconnect the building audible alarms at the gas alarm control panel.

6.2            Dismiss assisting technician at the gas alarm control panel.

6.3            Remove the ‘Fire Alarm Systems Testing in Progress’ notification signs previously posted.

6.4            Notify the SOTR that the tests are complete and system is on-line and operational.  Allow SOTR to verify that the system is in normal operating condition.

6.5            Allow personnel to return to the area previously designated as hazardous.

 

7.0          Conclusion

 

Upon completion of the procedure, the gas detection system is on-line and operational.

 

8.0          References

 

·       U.S.I's Two-Stage Alarm Gas Detector 0 & M manual; CALIBRATION and MAINTENANCE Sections

 

 

 

ISSUING AUTHORITY

APPENDIX AUTHOR

APPROVAL DATE

EXPIRATION DATE

REV.

 

 

Fire Protection Dept

Tim Minga

06/15/2011

06/15/2016

0

 

This document is controlled as an on line file.  It may be printed but the print copy is not a controlled document.  It is the user’s responsibility to ensure that the document is the same revision as the current on line file.  This copy was printed on 6/16/2011.