DPCNews 024 - Definitions for EN 1330-7:2005 standard

Written by Administrator
Saturday, 01 May 2010 10:20

May 2010
Document updated in January 2013

Suggested definitions of some MT terms left out of the EN 1330-7:2005 standard

In our paper titled "MT Lexicon (English/French)" published in March 2010 on our Website, we gave a translation in French of many terms used in MT. 

Definition of some of them is given in the EN 1330-7:2005 standard.

Due to technical improvements of MT, such as new magnetisation techniques or new devices to make MT a more reliable method, we think it useful to introduce new terms.

Readers may find underneath definitions we suggest for some entries "forgotten" in the standard.

Some terms are used for both PT and MT, especially those relating to lighting and viewing conditions.



Blue haze/Brouillard bleu

Shady view due to the fluorescence emitted by organic molecules in the vitreous humour of the eye under the influence of UV-A if UV blocking goggles are not worn.

Combined radiometer-luxmeter/Combiné radiomètre-luxmètre

Digital meter used to measure both the (UV-A or blue light) irradiance and the (visible light) illuminance.


Ratio between the illuminance given by a discontinuity indication and that by the surrounding background.

Cut-off wavelength - Cut-off/Coupure

Frequency or wavelength where the measurement efficiency of an instrument device drops below a specified value, close to zero, under defined conditions.
Also, frequency or wavelength where a physical parameter (often a sound, a light, an electric signal) has dropped by √2/2 .

Demagnetizing unit/Démagnétiseur

Equipment used to set the residual magnetization to an acceptable figure.

Digital luxmeter/Luxmètre numérique

Digital meter used to measure the (visible light) illuminance.

Digital radiometer/Radiomètre numérique

Digital meter used to measure the (UV-A or blue light) irradiance.

Dry powder dispenser/Pulvérisateur de poudre sèche

Hand-held item used to spray dry powders.

Dual purpose detection media/Produit indicateur mixte

Detection media visible both under UV-A radiation and white light.

Flash magnetization/Aimantation éclair

Magnetization by a current impulse of short duration obtained by capacitor discharging.

Fluorescent transparent comparator/Comparateur d’indications fluorescentes

Transparent stiff plastic ruler containing drawings of geometrical shapes (lines, circles, etc.) of generally green colour in visible light and fluorescent under UV-A radiation allowing for assessing the dimensions of indications.

Full width spectral at half maximum (FWSHM)/Largeur spectrale à mi-hauteur (LSMH)

Band width of wavelengths for which the irradiance or the illuminance (as appropriate) is at 50% of the peak value.

Headstock/Épanouissement polaire fixe

Mass in full or laminated ferromagnetic material being a part of the magnetic circuit (or electromagnet) of a magnetic bench and which is used as interface with the part under inspection to provide an adequate magnetic flux circuit. A bench comes with two stocks, generally one fixed (headstock) and one mobile (tailstock: see this term).

Induced light source/Lampe à induction

UV-A radiation or white light source fitted on portable electromagnets which lights on by induction.

Lift test bar/Barreau pour test de soulèvement

Ferromagnetic parallelepipedic steel block, whose mass is 4.5 kg (for AC magnetic fields) or 18 kg (for DC or AC rectified magnetic fields), used to carry out the periodic functional test of permanent magnets and portable electromagnets.

Longitudinal magnetization/Aimantation longitudinale

Magnetization where the magnetic field lines are essentially parallel to the longitudinal axis of a part under inspection, allowing for detecting transverse discontinuities.

Magnetic flux density indicator/Indicateur d’induction magnétique

Compass-like item with a pointer or an analog or digital display to measure residual magnetisation. The pointer-equipped version cannot be calibrated.

Non-contact technique by induced current flow/Technique d’aimantation sans contact par passage de courant induit

Technique in which the part (ring or pipe-shaped part for instance) is considered as the secondary of a transformer. The primary circuit is a cable, going through the hole of the part.  The primary of the transformer is generally the magnetic circuit or the electromagnet of the magnetic bench.

Pear shaped centrifuge tube/Poire - tube de sédimentation - ampoule à décanter

Graduated tube to measure the solid content of a liquid. It DOES NOT measure the magnetic particle content of a magnetic ink. . It is designed only to check that the content of solid particles of a brand-new magnetic ink meets the supplier's or prime's specification.

Permanent magnet/Aimant permanent

Set of two magnetic (North and South) poles which, spaced out one from the other one and applied on the test surface, induce a true DC magnetic field in the area of the part between both poles.

Reference photography baseline - Reference picture baseline/Photographie initiale de référence

Photograph taken on BRAND NEW reference test block or panel.
This photograph will be the ONLY one used for all the lifetime of this reference test block or panel.

Residual or remanent magnetization/Aimantation résiduelle ou rémanente

Magnetization remaining in a part after the shut-off of the magnetising field/current.

Swinging field technique/Technique d’aimantation par champ tournant

Technique in which the magnetization vector turns very quickly to allow for the detecting of all defects (regardless of their direction) in a single shot. This is generally achieved by using 2 phases of a 3-phase main power source. A phase gives the longitudinal magnetization while the second phase gives the transverse magnetization. Both magnetizations shall be balanced. Due to the delay between phases, the magnetization vector scans all the directions on 360°. Equipment may be either a magnetic bench with the current flow technique for the transverse magnetization and with the magnetic flow technique for the longitudinal magnetization, or a non-contact unit (multidirectional magnetization chamber or an inspection equipment by induced current).

Tailstock/Épanouissement polaire mobile

The mobile stock of a magnetic bench, allowing for fitting parts of a large range of lengths. See the"headstock" entry.

Transverse magnetization/Aimantation transversale

Magnetization where magnetic field lines are essentially perpendicular to the longitudinal axis of the part under inspection. If the part is cylinder-like, this magnetisation is also called circular magnetisation. It allows for detecting longitudinal discontinuities.

UV-A or blue light source/Projecteur UV-A ou de lumière bleue

Source of UV-A radiation or of blue light.

(UV-A or blue light) irradiance/Éclairement énergétique (UV-A ou lumière bleue)

Power of (UV-A or blue light) electromagnetic radiation received per surface area unit to be inspected.

UV-A overhead source/Plafonnier UV-A

UV-A source secured to the ceiling or overhanging the inspection area.

(Visible light) illuminance/Éclairement lumineux (lumière visible)

Quantity of (visible light) luminous flux received per surface area unit to be inspected.

Wood's glass filter/Filtre de Wood

UV-B and UV–C blocking filter letting violet and infrared radiations pass through along with UV-A radiation.

Of course this list is not all-comprehensive and it will be updated when needed.

We hope that the Technical Group in charge of the EN 1330-7:2005 standard revision will eventually consider our suggestions.


• EN 1330-7:2005 Non-destructive testing Terminology Part 7: Terms used in magnetic particle testing, European Committee for Standardization, Brussels, Belgium, 2005.

We, Pierre CHEMIN and Patrick DUBOSC, welcome any comment, any idea. If you have some examples you would like to see discussed here, please give us all the useful indications. If you require confidentially, we would modify locations, names and some parameters to prevent any traceability.
Nevertheless, we are convinced that our site may be a kind of surge-valve: the topic is NOT to target this company, or that auditor; but it is always to make users think, to make them ask themselves, or others, the right questions.

We may also give advice, once again on a confidential basis if needed: please, feel free to ask questions, to document our data basis: about Material Safety Data Sheets (MSDS), about environment, a chemical name you don't understand, a Penetrant process you have heard about, etc.
We have plenty of examples, some being out of all the specifications/standards, which led to the discontinuities detection, when the "current, normal, processes" prevented discontinuity finding.

Last Updated ( Thursday, 13 June 2013 16:42 )