A tracer-gas leak testing method is a

nondestructive testing Nondestructive testing (NDT) is any of a wide group of analysis techniques used in science and technology industry to evaluate the properties of a material, component or system without causing damage. The terms nondestructive examination (NDE), n ...

method that detects gas leaks. A variety of methods with different sensitivities exist. Tracer-gas leak testing is used in the

petrochemical industry file:Jampilen Petrochemical Co. 02.jpg, 300px, Jampilen Petrochemical co., Asaluyeh, Iran The petrochemical industry is concerned with the production and trade of petrochemicals. A major part is constituted by the plastics industry, plastics (poly ...

, the

automotive industry The automotive industry comprises a wide range of company, companies and organizations involved in the design, Business development, development, manufacturing, marketing, selling, Maintenance, repairing, and Custom car, modification of motor ve ...

, the

construction industry Construction are processes involved in delivering buildings, infrastructure, industrial facilities, and associated activities through to the end of their life. It typically starts with planning, financing, and design that continues until the ...

and in the manufacture of

semiconductors A semiconductor is a material with electrical conductivity between that of a conductor and an insulator. Its conductivity can be modified by adding impurities (" doping") to its crystal structure. When two regions with different doping levels ...

, among other uses.

Types

Several tracer-gas leak testing methods exist, including: * Detection of leaks using

helium mass spectrometer A helium mass spectrometer is an instrument commonly used to detect and locate small leaks. It was initially developed in the Manhattan Project during World War II to find extremely small leaks in the Gaseous diffusion, gas diffusion process of enri ...

, which provides high sensitivity * Hydrogen leak testing, which provides the best mobility * Refrigerant gas leak detection, for refrigeration applications

Method selection

Typical leakage rates

The nature of the product or the process and the process gases will set the leak rate requirement:

Sensitivity of methods

Based on the target leak rate, the table below will help to choose the most suitable method.

Applications

Typical applications of tracer-gas leak testing include: * In petrochemical plants, hydrocracking, vapocracking,

catalytic reforming Catalytic reforming is a chemical process used to convert petroleum naphtha, naphthas from crude oil into liquid products called reformates, which are premium "blending stocks" for high-octane gasoline. The process converts low-octane linear hydr ...

, and

steam reforming Steam reforming or steam methane reforming (SMR) is a method for producing syngas (hydrogen and carbon monoxide) by reaction of hydrocarbons with water. Commonly, natural gas is the feedstock. The main purpose of this technology is often hydrogen ...

are all

hydrogen Hydrogen is a chemical element; it has chemical symbol, symbol H and atomic number 1. It is the lightest and abundance of the chemical elements, most abundant chemical element in the universe, constituting about 75% of all baryon, normal matter ...

-based processes, in which were hydrogen leak testing is required. * When manufacturing

, all processes taking place in a process chamber at atmospheric pressure or under vacuum – diffusion, oxidation, LPCVD, PECVD, PVD and

ion implantation Ion implantation is a low-temperature process by which ions of one element are accelerated into a solid target, thereby changing the target's physical, chemical, or electrical properties. Ion implantation is used in semiconductor device fabrica ...

– require helium or hydrogen leak testing. * In vehicles, airbags have to be tested for leaks so they remain functional for a long time. As well as airbags, the

air conditioning Air conditioning, often abbreviated as A/C (US) or air con (UK), is the process of removing heat from an enclosed space to achieve a more comfortable interior temperature, and in some cases, also controlling the humidity of internal air. Air c ...

system, fuel system, and exhaust system require testing for leaks. * Pacemakers and

catheters In medicine, a catheter ( ) is a thin tube made from medical grade materials serving a broad range of functions. Catheters are medical devices that can be inserted in the body to treat diseases or perform a surgical procedure. Catheters are man ...

have to be tested for efficacy and longevity. * On planes, tracer-gas leak testing is used to quickly and safely locate fuel leaks, as well as to check oxygen distribution devices and

cabin pressurization Cabin pressurization is a process in which conditioned air is pumped into the aircraft cabin, cabin of an aircraft or spacecraft in order to create a safe and comfortable environment for humans flying at high altitudes. For aircraft, this air i ...

systems. * Refrigeration and air conditioning must have the lowest possible rate of loss of

refrigerant A refrigerant is a working fluid used in the cooling, heating, or reverse cooling/heating cycles of air conditioning systems and heat pumps, where they undergo a repeated phase transition from a liquid to a gas and back again. Refrigerants are ...

gases (contributing to

ozone depletion Ozone depletion consists of two related events observed since the late 1970s: a lowered total amount of ozone in Earth, Earth's upper atmosphere, and a much larger springtime decrease in stratospheric ozone (the ozone layer) around Earth's polar ...

). * Sewage and drinking water networks, to reduce loss of water and make sure drinking water is not contaminated by sewage.

Standards

Several standards apply to leak testing and more specifically to tracer-gas leak testing methods, for example: * BS EN 1779:1999; leak tightness by indication or measurement of gas leakage, * BS EN 13185:2001 Non-destructive testing. Leak testing. Tracer gas method, * BS EN 13192:2002 Non-destructive testing. Leak testing. Calibration of reference leaks for gases.

References

{{DEFAULTSORT:Tracer-Gas Leak Testing Method Tests Nondestructive testing Hydrogen technologies