Gas Testing and Purging Certificates
Whether you are building a new natural gas pipeline or installing LPG pipework in a new installation, you will need to have it tested and purged. It is essential to prevent hazardous gases from combining with the air, causing explosions. It is also essential for those workers who are breathing toxic gas.
Two types of purge tests are available: LPG and piping. In a piping purge, a high volume of heavy gas is intermittently injected into the piping system, in order to remove particulate matter. LPG purge is a different process. LPG, however, is more heavy than air. As a result, the purge gas has to be ignited as quickly as possible. Incorrect LPG purge can cause toxic gas buildup that can be dangerous to the health of employees.
A piping purge is an inert gas that is injected into the pipework to clear it of flammable gas and other contaminants. The purge gas is most often nitrogen. If necessary, a small amount can be added to the purge gas. It is important that the purge gas is not left unattended, because it can contain corrosive liquids that can damage the gas detection equipment.
The purging procedures for LPG have changed, to better reflect the current standards. These changes include changes in the size of DN25 and DN28 pipework. There are also changes in the tightness test, including the use of fuel for certain installations. These changes affect the inspection of LPG cylinders.
A safety checklist is also included. This includes the selection of blowpipes, flashback arrestors and gauges. The list also includes instructions on thread directions. The tightness test requires the detector to be calibrated for fuel and gas type. In the case of defective sensors, the environmental range may not be measured.
Gas operatives can use the Gas Testing and Purging Form to document their findings and prepare a Safety Report. This form must be completed in order to register as Gas Safe. The form is also available online via the ServiceM8 App. You can create commercial gas certificates from anywhere with the app. The app can be downloaded and used to create commercial gas certificates on the go.
The purging and tightness test are both a crucial part of ensuring that the installation is safe for use. These tests are performed at specified pressures. It is essential to prepare a complete risk assessment and a method plan before you perform any of these tests.
The IGEM/UP/1B Edition 3 was released recently. It includes significant improvements to tightness testing procedures and direct purging. These changes include changes to DN28 and DN25 pipework, and the method of measuring installation volumes. There is a separate section on tightness testing for fuel gas pipework, detailing the risks associated with working in this area.
The NG purge procedure has also undergone revisions. This includes changes to a sub-section.