Iowa Administrative Code › Agency 661 - Public Safety Department › Chapter 226 - Liquefied Petroleum Gas › Rule 661-226.5 - Pressure Testing

Current through Register Vol. 47, No. 3, July 24, 2024
(1)
			 Pressure testing required. After assembly and after any modification or repair,
			 metallic LP-gas piping and hose shall be pressure-tested as follows:
a. Piping systems having operating pressures
			 greater than 20 psig shall be pressure-tested in accordance with the following:
(1) Prior to acceptance and initial
			 operation, all piping installations shall be visually inspected and
			 pressure-tested to determine that the materials, design, fabrication, and
			 installation practices comply with the requirements of this chapter.
(2) Inspection shall consist of visual
			 examination, during or after manufacture, fabrication, assembly, or pressure
			 tests as appropriate.
(3) When
			 repairs or additions are made following the pressure test, the affected piping
			 shall be tested. Minor repairs and additions are not required to be
			 pressure-tested, provided that the work is inspected and connections are tested
			 with a noncorrosive, leak-detecting fluid or other leak-detecting methods
			 approved by the authority having jurisdiction.
(4) When new branches are installed to a new
			 appliance or appliances, only the newly installed branch or branches shall be
			 required to be pressure-tested. Connections between the new piping and the
			 existing piping shall be tested with a noncorrosive, leak-detecting fluid or
			 approved leak-detecting methods.
(5) A piping system shall be tested as a
			 complete unit or in sections. A valve in a line shall not be used as a bulkhead
			 between gas in one section of the piping system and test medium in an adjacent
			 section, unless a double block and bleed valve is installed. A valve shall not
			 be subjected to the test pressure unless it can be determined that the valve,
			 including the valve-closing mechanism, is designed to safely withstand the
			 pressure applied during the test.
(6) Regulator and valve assemblies fabricated
			 independently of the piping system in which they are to be installed shall be
			 permitted to be tested with inert gas or air at the time of
			 fabrication.
(7) Prior to testing
			 the system, the interior of the pipe shall be cleared of all foreign
			 material.
(8) The test medium shall
			 be air, nitrogen, carbon dioxide, or an inert gas. Oxygen shall not be
			 used.
(9) Test pressure shall be
			 measured with a pressure-measuring device designed and calibrated to read,
			 record, or indicate a pressure loss due to leakage during the pressure test
			 period. The source of pressure shall be isolated before the pressure tests are
			 made. Mechanical gauges used to measure test pressures shall have a range such
			 that the highest end of the scale is not greater than five times the test
			 pressure.
(10) The test pressure to
			 be used shall be no less than 50 psi and shall not exceed 75 psi.
(11) Expansion joints shall be provided with
			 temporary restraints, if required, for the additional thrust load under
			 test.
(12) Appliances and equipment
			 that are not to be included in the test shall be either disconnected from the
			 piping or isolated by blanks, blind flanges, or caps. Flanged joints at which
			 blinds are inserted to blank off other equipment during the test shall not be
			 required to be tested.
(13) Where
			 the piping system is connected to appliances or equipment designed for
			 operating pressures of less than the test pressure, such appliances or
			 equipment shall be isolated from the piping system by disconnecting them and
			 capping the outlet(s).
(14) Where
			 the piping system is connected to appliances or equipment designed for
			 operating pressures equal to or greater than the test pressure, such appliances
			 or equipment shall be isolated from the piping system by closing the individual
			 appliance or equipment shutoff valve(s).
(15) All testing of piping systems shall be
			 performed in a manner that protects the safety of employees and the public
			 during the test.
(16) Test duration
			 shall be not less than one-half hour for each 500
			 ft3(14 m3) of pipe volume
			 or fraction thereof. The duration of the test shall not be required to exceed
			 24 hours.
EXCEPTION: When a system having a volume of less than 10
				ft3(0.28 m3) is tested,
				the test duration shall be a minimum of 10 minutes.