CLASS D - SENSITIVE LEAK TEST GAS AND BUBBLE METHOD. 1.1 To provide definitive requirements for PNEUMATIC pressure testing of piping systems.

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1 Page 1 of 7 CLASS D - SENSITIVE LEAK TEST GAS AND BUBBLE METHOD 1. SCOPE 1.1 To provide definitive requirements for PNEUMATIC pressure testing of piping systems. 1.2 The piping system as used herein is intended to include the pipe, valves and fittings. Vessels, process equipment, instruments and relief devices are not included Option: Flanged connections, packings of valves, and instruments which can produce leaks to the environment, may be included in this test, at the owner s discretion. 1.3 The acceptance of piping systems under this specification is for pressure tightness only. 1.4 This Leak Test procedure qualifies as a Sensitive Leak Test as per ASME B31.3, para CLASS D-- SENSITIVE LEAK TEST GAS AND BUBBLE METHOD: 2.1 This test is performed by pressurizing the system with a gas, to 1 BAR (15 psig). This creates a pressure differential across a leak. Leaks are detected by applying a commercial bubble forming solution to all joints. The locations of leaks are indicated by the formation of bubbles This test may be performed at pressures greater than 1 BAR (15 psig). However, all conditions of G4S and G4Q shall be met when a higher pressure is used. 2.2 A complete line or section of line containing several valves and branches may be tested at one time. 2.3 CAUTION: PNEUMATIC TESTING should be used only as a last alternative. Carefully planned and supervised procedures shall be used to guard against the hazards of latent energy of compressed gases. 2.4 The Owner is responsible to assure that all conditions and safety concerns identified in G4D are addressed. 3. TEST MATERIALS AND SERVICES

2 Page 2 of The detection fluid shall be a commercial bubble forming test fluid, such as SNOOP or SHERLOCK, or equivalent. Soaps, detergents and/or industrial compounds that are designated specifically to be used as cleaning agents shall not be used in bubble forming solutions. SNOOP is a registered trademark of the Nupro Co., Willoughby, Ohio.SHERLOCK is a registered trademark of Winton Products Company, Inc., Charlotte, North Carolina For testing of stainless steel, nickel or chromium alloys, the fluid shall have a sulfur and halogen content of less than 10 ppm of each For testing of parts made of polyethylene or structural plastic, the test fluid shall not promote environmental stress cracking (E.S.C.) For testing of oxygen systems, the test fluid shall meet the requirement of MIL-L-25567D. 3.2 Air compressors shall be equipped with discharge filters for removal of water, oil and foreign matter. Maximum discharge temperature of lubricated air compressors shall be 150C (300F). 3.3 Pneumatic tests shall be made with air, nitrogen or other gases, as specified in the technical job instructions, work order or construction order. 4. PREPARATION FOR TEST 4.1 The line schedule issued should give the Common Product Piping Specification for each line and may include material, size, insulation, etc., and the required Test Pressure, Test Class (Method) and other requirements of the pipe specifications A set of marked-up or highlighted Piping and Instrument Drawings (P&ID s) may be used. The purpose is to identify the boundaries of separate piping systems to be tested, the locations of isolation blanks, valve positions, double block and bleed valve arrangements, location of pressure injection or connection points, location of pressure gauge(s), recorders for pressure, temperature and other instrumentation used to validate the test. 4.2 In the absence of a line schedule, the Test Pressure and Test Class (Method) required may be covered in the job Piping Material Specification, contract technical job instructions, construction order, or for maintenance jobs, by Work Order. If not specified, refer to the appropriate Common Product Pipe Specification.

3 Page 3 of Prior to testing, a thorough visual inspection shall be made for defects such as improper materials, poor gasket installation and loose joints. All bolts shall be made up tight in the system to be tested. The surface of the piping to be tested shall be clean and free of oil, grease, paint, weld slag, or other contamination. Weld joints shall not be painted or covered before performing this test. 4.4 Pneumatic testing shall be done before hydrostatic testing (Class C), if hydrostatic testing is also specified. 4.5 Flanged joints may be taped shut using a suitable adhesive coated paper tape such as duct tape or masking tape When tape is used, the tape shall be applied very carefully to insure an airtight seal all around both flanges. A small vent hole shall be punched in the tape, at a location preferably on top. 4.6 Piping systems connected to equipment shall be isolated from the equipment by means of a line blind, prior to cleaning and testing. If a valve is connected to the equipment, the blind shall be between the valve and the equipment, with the valve in the open position Where piping can not be isolated from equipment for testing, or it is desirable to include equipment in leak testing, the equipment may be included in the test provided: The piping system Test Pressure does not exceed either manufacturer s test pressure or a pressure limit imposed by the position and condition of the equipment The equipment does not contain any internals or materials that may be damaged by testing No rotating equipment may be included in any piping system leak test. 4.7 Valves shall be left open during the testing. If a valve is located at the end of a line, a blind flange or plug shall be installed. Where a valve can not be tested in the open position, consider: Blank the upstream side of the valve Remove the valve and install a blind flange Remove the valve and install a flanged test spool where continuity of the line is required for purpose of the test.

4 Page 4 of Test blinds shall be installed between existing piping and new piping to prevent introducing cleaning and testing medium into existing lines, or pressurizing the existing system Test blinds shall be capable of withstanding the test pressure. 4.9 Leak tests shall include as much instrument process piping as possible. Where an instrument process line contains more than one block valve, all valves shall be open except the one nearest the instrument Instruments and similar special equipment shall be protected against overpressure during cleaning and testing by disconnecting the piping between the closed block valves and the instruments. Direct operated or self-contained regulators and float actuated devices are to be removed or blocked and vented Control valves, pressure reducing valves, level controllers, level switches, orifice plates, turbine meters, massflow meters, vortex meters and other instruments or fittings designated by the Owner, shall be removed from the lines before cleaning and replaced before testing. All such items shall be cleaned separately after removal. Where control valves are closed, the line shall not be tested until the valve has been opened by the Owner. The line bore orifice spacers and gaskets or spare rings furnished with meter runs shall be installed prior to cleaning and remain in place during testing Check available drawings for any specific installation or operating instruction pertaining to expansion joints. Test pressure shall not exceed the maximum allowable specified test pressure of the expansion joint Expansion joints having tie-rods shall be tested as part of the piping system unless otherwise specified. The tie-rod nuts must be hand tight, with no slack under the outside nuts Expansion joints not having tie-rods may be removed or isolated from the test Insulation will not be allowed on systems under test except on those parts which have had a documented certified shop or mill test Spring support travel stops shall not be removed until all testing has been completed Prior to administration of the test visually observe the

5 Page 5 of 7 piping system to assure it is properly prepared. 5. ADMINISTRATION OF TEST 5.1 All tests shall be witnessed and accepted by the Owner or Owner designee The presence of the Owner or Owner designee is not necessary while initial checking of lines for leaks is in progress. 5.2 Special precautions shall be taken if testing is to be performed in the open air, with regard to weather such as wind or rain or other influences which may affect the accuracy of the test results Portable shields may be erected around areas to be tested, if necessary to prevent weather conditions from interfering with bubble leak tests The surface temperature of the piping or component to be tested shall be from 4 Deg C (40 Deg F) to 52 Deg C (125 Deg F) inclusive, throughout the test. Local heating or cooling is permitted provided the surface temperature remains within the stated range during the test. Bubble leak testing may be performed when the surface temperature is colder than 4 Deg C (40 Deg F) provided that a commercial bubble forming solution is used that is specifically manufactured for bubble leak testing at the coldest surface temperature that will be encountered during the test. 5.3 Illumination at the specific test area shall be a minimum of 1000 lux (100 footcandles). Verification of illumination is not required for external bubble leak tests performed during daylight hours. Otherwise, the light source, technique and illumination verification by light meter shall be demonstrated one time and documented. 5.4 Access to the area being bubble leak tested shall be sufficient to place the eye within 0.6 m (24 inches) of the surface under immediate observation. The angle between the line of sight and the surface under immediate examination shall not be less than 30 degrees. Mirrors may be used to improve the angle of vision. 5.5 Pressure gauges shall be of a suitable scale capacity for the Test Pressure, having a dial at least 115 mm (4-1/2 ) in diameter. The Test Pressure should be approximately 60% of full scale. The maximum pressure capacity shall not exceed three times the particular Test Pressure. Gauges will have established traceable identities and shall be accurate to within 1% of full scale. There

6 Page 6 of 7 shall be a minimum of two pressure gauges for each test Pressure gages used for testing shall be calibrated at least every six months. Calibration shall be traceable to individual gages for verification. Records of calibration shall be made available upon request. 5.6 The pressure differential should be created before the fluid is applied, to prevent clogging of small leaks. Prior to the beginning of bubble testing, the test pressure shall be held for a minimum of 15 minutes A commercial bubble test fluid shall be applied to all joints under examination, including each vent hole for taped flanges, flanged joints, valves stems, packing glands, and completely coat each threaded or welded joint Care shall be used in applying the fluid, to prevent the formation of bubbles; the bubble forming solution shall be applied by spraying, brushing or flowing the solution onto the test area such that a thin film of solution covers the area The surface shall be examined at the time of the solution application for the presence of large leaks, and after 2 minutes for the presence of small leaks Leaks detected shall be marked for correction and the subsequent inspection. 5.7 The first leakage check shall be made at 0.3 BAR (5 psig) MAXIMUM. Any detectable leaks shall be eliminated before proceeding. The leakage test may be repeated at higher pressures not to exceed 1 BAR (15 psig) or the specified test pressure, whichever is lower, as approved by the Owner. 5.8 Variations of pressure and volume due to temperature changes will be taken into account in determining whether the pressure during test is satisfactory, at the end of the test. All attempts shall be made to stabilize the temperature of the test, prior to starting the test. 5.9 Over tightening of a valve in an effort to make it hold may be cause for rejection of the valve by the Owner.

7 Page 7 of 7 6. RETESTS 6.1 In the event that a piping system or any part fails to pass the test prescribed, a new test shall be applied after repairs and corrections have been made. This retest shall include all parts of a connected system which may have passed a test previously, but have been affected by the corrections made or by a delay attending to the corrections. 7. POST TEST 7.1 At the completion of the test, all blinds, plugs and caps used to isolate equipment, vessels and instruments shall be removed, flange faces and threads inspected for damage, and piping reconnected. Special care is required when reconnecting these points to avoid leaks. 7.2 New gaskets shall be used when re-installing flanged items or reconnecting to flanged equipment. Gaskets removed after tests shall not be reused. 7.3 Vent and drain connections shall be capped, plugged or blanked after completion of test according to pipe specifications or technical job instructions. 7.4 All valves shall be placed in the open or closed position as determined by the Owner.