FITOK products are widely used across industries including semiconductor, hydrogen, oil & gas, chemical, power and liquid cooling, each with its own specialist terminology and technical abbreviations.

FITOK has compiled this glossary of commonly used technical abbreviations to help customers and partners better understand the terminology and support clear, accurate technical communication.

Available through NVFCL, FITOK’s only authorised distributor in the UK & Ireland.

FITOK Technical Abbreviations

ALD – Atomic Layer Deposition
A thin-film deposition process that deposits material one atomic layer at a time. Widely used in semiconductor and microelectronics manufacturing.

ALE – Atomic Layer Etching
A highly precise etching process that removes material one atomic layer at a time. Generally regarded as the reverse process of ALD.

AOD – Argon Oxygen Decarburization
A stainless steel refining process that reduces carbon content by blowing a mixture of argon and oxygen while minimising alloy loss.

BA – Bright Anneal
A heat treatment process performed in a protective atmosphere to produce a bright, oxide-free metal surface.

BSPP – British Standard Pipe Parallel
A British standard 55° parallel pipe thread that typically seals with a gasket or O-ring rather than the threads themselves.

BSPT – British Standard Pipe Taper
A British standard 55° tapered pipe thread that achieves sealing through thread interference.

CDA – Clean Dry Air
Oil-free, moisture-free, highly filtered compressed air used in semiconductor, pharmaceutical and other clean manufacturing processes.

CFOS – Clean for Oxygen Service
Indicates that a product has been specially cleaned to remove contaminants that could create fire or explosion hazards in oxygen service.

CHSS – Compressed Hydrogen Storage System
Equipment or systems designed for storing compressed hydrogen in hydrogen energy applications.

CPT – Critical Pitting Temperature
The lowest temperature at which stable pitting corrosion initiates under specified test conditions. An important indicator of a material’s pitting corrosion resistance.

CVD – Chemical Vapor Deposition
A process that deposits solid thin films through chemical reactions of gaseous precursors on a substrate surface. Widely used in semiconductor, photovoltaic and surface coating industries.

DESO – Double-End Shutoff
Both ends of the coupling are equipped with self-closing valves, allowing fluid flow on both sides to be shut off simultaneously when disconnected.

EP – Electropolish
An electrochemical finishing process that improves surface smoothness, cleanliness and corrosion resistance.

ESR – Electroslag Remelting
A remelting process that improves material cleanliness, microstructure and mechanical properties.

FLNG – Floating Liquefied Natural Gas Facility
An offshore floating facility integrating natural gas production, liquefaction, storage and offloading.

FPSO – Floating Production Storage and Offloading
An offshore floating production facility that integrates oil production, storage and offloading functions.

HPU – Hydraulic Power Unit
A system that supplies pressurised hydraulic fluid to hydraulic equipment.

IGS – Integrated Gas System
An integrated system used to control gas in the semiconductor industry, incorporating valves, fittings, piping components and measuring and control instruments.

LOTO – Lockout & Tagout
A safety procedure used to prevent accidental operation or unintended startup of equipment that has been shut down.

LRV – Log Reduction Value
A logarithmic measure of filtration efficiency. For example, 99.9999% removal efficiency equals 6 LRV.

MP – Mechanical Polish
A mechanical finishing process used to reduce surface roughness and improve surface finish.

NPT – National Pipe Thread
A U.S. standard 60° tapered pipe thread typically used with thread sealant or PTFE tape.

OS&Y – Outside Screw and Yoke
A valve design with an externally threaded rising stem supported by a yoke, commonly used in gate and globe valves.

POU – Point of Use
The location where gases, fluids or chemicals are ultimately delivered for consumption by equipment or processes.

ppm – Parts Per Million
A concentration unit representing one part per million parts of a substance.

PREN – Pitting Resistance Equivalent Number
A calculated index based primarily on chromium, molybdenum and nitrogen content that estimates the pitting corrosion resistance of stainless steels.

PSI – Pounds per Square Inch
An imperial unit of pressure.

PSIA – Pounds per Square Inch Absolute
Pressure referenced to absolute vacuum.

PSID – Pounds per Square Inch Differential
The pressure difference between two measurement points.

PSIG – Pounds per Square Inch Gauge
Pressure measured relative to atmospheric pressure.

PVD – Physical Vapor Deposition
A process in which materials are deposited onto a substrate through physical methods such as evaporation and sputtering.

SCCS – Standard Cubic Centimeters per Second
A gas flow unit commonly used to express leak rates under standard reference conditions.

SCFM – Standard Cubic Feet per Minute
A gas flow rate expressed in standard cubic feet per minute under specified reference conditions.

SESO – Single-End Shutoff
A quick-disconnect design in which only one side automatically closes upon disconnection.

SLPM – Standard Liters per Minute
A gas flow rate expressed in standard litres per minute under specified reference conditions.

SPE – Supply Pressure Effect
The degree to which changes in inlet pressure affect the outlet set pressure of a pressure regulator.

UHP – Ultra High Purity
Refers to extremely high-purity gases, fluids or systems used in contamination-sensitive industries.

UHP – Ultra High Pressure
Refers to fluid systems operating at pressures significantly higher than conventional industrial pressure ranges.

UQD – Universal Quick Disconnect
A tool-free quick-disconnect coupling designed primarily for liquid cooling systems.

UQDB – Universal Quick Disconnect Blind-Mate
A quick-disconnect coupling featuring blind-mating and self-alignment functionality, ideal for limited-space or hard-to-reach applications.

VAR – Vacuum Arc Remelting
A remelting process using an electric arc in a vacuum to improve material purity, density and microstructural uniformity.

VCR – Vacuum Coupling Radius
A metal face-seal connection commonly used in semiconductor process systems and suitable for applications ranging from cryogenic to high-temperature and high-vacuum to high-pressure conditions.

VIM – Vacuum Induction Melting
A melting process in which metal is melted by electromagnetic induction in a vacuum, improving material purity.

VMB – Valve Manifold Box
A gas distribution enclosure integrating valves, regulators, filters and monitoring devices, commonly used for hazardous specialty gases.

VMP – Valve Manifold Panel
A valve control panel used to distribute and control process gases in centralised gas supply systems.

Find the Right FITOK Solution with NVFCL

As FITOK’s only authorised distributor in the UK & Ireland, NVFCL provides access to FITOK’s extensive range of valves, fittings and fluid control solutions, alongside product information and technical support.

Whether you’re looking for a solution for a demanding industrial application or require guidance on selecting the right product for your system, our team can help.

Get in touch with NVFCL to discuss your requirements and find the right FITOK solution for your application.