Glossary of terms used on this site

A sensor in which galvanic corrosion is used to determine the concentration of a target gas. Galvanic corrosion occurs when two dissimilar metals are in contact with each other in the presence of an electrolyte, such as salt water, forming a galvanic cell with hydrogen formation on the more noble metal. The resulting electrochemical potential then develops an electric current that electrolytically dissolves the less noble material. By measuring the electric current, the concentration of the target gas can be calculated.

One of the four fundamental states of matter (the others being solid, liquid, and plasma). A pure gas may be made up of individual atoms (e.g. a noble gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or compound molecules made from a variety of atoms (e.g. carbon dioxide). A gas mixture, such as air, contains a variety of pure gases. What distinguishes a gas from liquids and solids is the vast separation of the individual gas particles. This separation usually makes a colorless gas invisible to the human observer.

A pressure vessel for storage and containment of gases at above atmospheric pressure. Generally used the gas detection field for storing and carrying calibration and/or bump test gases.

See: Colorimetric Gas Sampling Tube

A device that monitors the atmosphere for gases, typically oxygen, combustible gases and/or toxic gases. A portable detector sounds an alarm when concentrations cross threshold values.

A device to generate specific gases. For gas detection purposes, gas generators are typically used to generate a precise concentration of gas with which to calibrate or test gas detectors. Gas generators are used when the calibration gas is highly unstable in a gas cylinder, e.g. by its corrosiveness in contact with the gas cylinder wall.

In gas detection: To detect a gas and to quantify the concentration of that gas in the air.

Althoug many values are appropriate when discussing any gas, in gas detection, gas value means the concentration of a specific gas in a gas cylinder or in an environment.

Used to regulate the flow of gas from a gas cylinder. Various types are available, for example manually operated valves and demand flow regulators. Automatic bump test- and calibration stations are generally equipped with an electrically operated valve.

Calculates soil humidity by measuring the conductivity of the soil between two rod-shaped electrodes that are inserted into the ground. While normally an instrument in the agricultural industry to aid decision making about irrigation, they are also used at soil remediation sites: to prevent hazardous concentrations of contaminated dust in the air, ground moisture meters are used to assess the risk of this happening, enabling operators to prevent dust by spraying water on the remediation site.

A colourless, highly toxic, highly flammable gas with a characteristic pungent odour of rotten eggs. Hydrogen sulfide is most tightly associated with oil and gas extraction and refinement because H2S occurs naturally in crude oil in small amounts, while it can also occur in natural gas in large concentrations. Also, petroleum is desulfurized by converting the sulfuric compounds into H2S by adding hydrogen. While most people are able to smell H2S at concentrations as low as 0.47 ppb (0,00047 ppm), at concentrations above 100-150 ppm it quickly deadens the sense of smell, so victims may be unaware of its presence until it is too late. H2S is detectable with colorimetric tubes that are available from many manufacturers in a wide range of target concentrations. There are many electronic instruments available that can measure the concentration of H2S through an electrochemical cell. Hydrogen sulfide sensors are among the most widely used sensors for toxic gases in multigas instruments, in addition to oxyge- and combustibles sensors.

Generally, compounds that do not include carbohydrates.

Cause someone to lose control of their faculties or behaviour. See: Alcohol meter.

A temperature scale with absolute zero as its null point indicated with K, with the same magnitude as the Celsius scale. As the Kelvin scale is defined absolutely, it is an SI standard.

An easy-to-use pump system that allows for quick sampling with suitable colorimetric gas sampling tubes.

Any system that was designed or is used to detect leaks in vessels, ducts, lines and the like. Leak detection systems include detectors for the leaking substance, ultrasound faults finding systems, and specialized (thermal) imaging systems. 7Solutions distributes a number of leak detection solutions.

A contract by which 7Solutions conveys the use of its gas detectors to its customer for a specified term in return for a periodic payment. 7Solutions offers financial and operational lease solutions for almost any gas detection instrument imaginable. Usually, lease is used for terms that span the economic life of gas detection instruments. For shorter term contracts, see Rental.

The minimum concentration of a combustible in air to be ignitable.

Any action that has the goal of keeping a piece of equipment in perfect working order or returning it to perfect working order. 7Solutions has its own maintenance and repair departments with decades of experience maintaining and repairing any type and brand of gas detection equipment.

An information sheet that describes the safety properties of a material, including guidelines for its safe handling, storage and transport. Includes toxicity information, usually along with maximum exposure warnings (TWA, STEL and/or ceiling values).