DAkkS-DKD calibration

The DKDcalibration laboratory, D-K-15030-01-00 of JENOPTIK Industrial Metrology Germany GmbH, has been accredited by the German Accreditation Body (DAkkS) in accordance with ISO/IEC 17025 since 1980. The laboratory works independently and has standards that have been set and calibrated by the National Metrology Institute (PTB).

Every single measurement on unknown standards and measurement devices is related to this reference standards, and can therefore be traced back to national standards in accordance with ISO 9000. This is confirmed by the internationally recognized DAkkS-DKD calibration certificate that comes under the ILAC agreement.

To ensure that the systems used to take the measurements produce correct and coherent results, they have to be regularly checked by an accredited calibration laboratory, so they can be traced back to national standards. You can therefore rest assured that the measured values are accurate and that measurement uncertainties are especially small.

Our DAkkS accredited DKD calibration laboratory is operated in accordance with strict quality benchmarks in a climate-controlled and vibration-minimized measurements room.

Accredited experts regularly carry out on-site monitoring visits during which the material and specialist personnel must provide evidence of their suitability.

Our DAkkS accredited DKD calibration laboratory issues DAkkS-DKD calibration certificates for roughness, form, contour and cam standards. Shaft measuring devices and surface profilers for measuring roughness – including on site, at the client's premises – can be calibrated to DAkkS-DKD standards. The calibration certificate documents the condition of the measuring device at the time of calibration.

DAkkS-DKD measurements are taken with the standards that are prescribed by and traced to the PTB. This ensures that the measurement results are uniform and independent. If a standard cannot be calibrated, you can obtain new standards from us.

For some calibrations, no DAkkS accreditation is currently possible, for example for roughness measuring systems with skid probes or for measuring devices. We do, however, also offer high-quality calibration services for these. Our trained staff use only standards that can be traced back to international SI units. 

For non-accredited parameters or as less expensive alternatives, we issue factory calibration certificates or factory test reports. For calibrations that do not come under the area of expertise of our calibration laboratory, we also work with selected external DAkkS-DKD calibration laboratories.

DAkkS-DKD calibration certificate

• Unique reference number
• Short description of the measurement procedure
• Reference standards used
• Standards applied (ISO...)
• Representation of the measurement results with their corresponding measurement uncertainties

DAkkS-DKD calibration certificates are internationally recognized as part of the ILAC agreement (International Laboratory Accreditation Cooperation).

ISO/IEC 17025

DAkkS accredited DKD calibration laboratories are accredited in accordance with the global ISO/IEC 17025 standard. This standard defines the general requirements for competence, quality management systems, impartiality and uniform working methods of these laboratories to promote confidence in the measurement results of DAkkS-DKD calibrations. Each DKD calibration laboratory, therefore, works in accordance with the requirements of this standard.

ILAC

ILAC, short for International Laboratory Accreditation Cooperation, is an international association of accreditation bodies that also include ISO/IEC 17025 accredited calibration laboratories. It manages international agreements with these calibration laboratories in the fields of compliance assessment and creates the framework conditions for international exchange of calibration services.

An ILAC accreditation ensures global acceptance of accredited testing and inspection reports, calibration certificates and the results of qualification tests. The calibration laboratories are permitted to use the combined ILAC-MRA mark (Mutual Recognition Arrangement) on calibration certificates within the scope of DAkkS accreditation.

IATF 16949:2016

IATF 16949 is a quality management system standard (QMS) that lays down the basic requirements for quality management systems in the automotive industry. This QMS standard is not stand-alone; it is only used in conjunction with standard ISO 9001. It clearly states that only accredited calibrations are permitted whenever an accreditation exists for this parameter. Factory calibrations are not permitted in this case.

In chapter 7.1.5.3.2, the standard specifies which requirements external laboratories must meet so they can be permitted to provide testing and calibration services. They are:

• Accreditation in accordance with ISO/IEC 17025 or a comparable standard
• The calibration service must be included in the scope of the accreditation
• The calibration certificate must bear the accreditation mark of the national accreditation body

ISO 21920

ISO 21920 is a new series of standards in the field of roughness measurement technology. It updates and compiles a wide range of roughness standards (ISO 4287, ISO 13565, and others) and replaces them. It simplifies design specifications and can, if necessary, be specified according to function and production needs with a high level of flexibility.

Since, in practice, we will continue to work with the old profiles for a long time, they will remain for existing designs. Modifications and new designs should, however, be issued in accordance with ISO 21920. Modifications to most measurement conditions and roughness parameters are low. When referred to the calibration results of roughness standards, the calibration values only change very slightly, and lie for the most part within the specified measurement uncertainty. The Rmax parameter is replaced by Rzx; measurement conditions can be selected by configuration class; filter designations lc and ls become Nic and Nis.

The DAkkS accredited DKD calibration laboratory of JENOPTIK Industrial Metrology Germany GmbH has been accredited in accordance with the ISO 21920 standards series. This means you can choose according to which standards you wish your standards to be calibrated.

Roughness book

The reference book entitled Roughness Measurement – Theory and Practice gives a thorough overview of roughness techniques based on practice. Dr Raimund Volk, R&D Fundamental Research Manager at JENOPTIK Industrial Metrology Germany GmbH and author of the book, explains roughness parameters, describes the structure of surface measuring devices, helps users, and makes it easier for designers to specify surface parameters. The book is the ideal companion for all those who want to become familiar with roughness measurement.

German National Metrology Institute (PTB)

The PTB in the national metrology institute of the Federal Republic of Germany. It is a research institute and higher federal authority of the Federal Ministry for Economy and Climate Protection that is responsible for measurement issues for science and economy. In Germany, the PTB is responsible for legally binding standards for measurement units that serve as a reference for any necessary calibrations.

The German Calibration Service (DKD) and the German Accreditation Body (DAkkS)

In the DKD, calibration laboratories of industrial companies, research institutes, technical authorities, monitoring and testing institutions founding merged when it was founded in 1977. On 3 May 2011, the DKD was re-founded as the technical committee of the PTB and accredited laboratories. This committee bears the name German Calibration Service (DKD) and comes under the aegis of the National Metrology Institute (PTB).

The guidelines and codes of practice drawn up by the DKD represent the state of the art in the relevant technical field and are available to the DeutschenAkkreditierungsstelleGmbH (German Accreditation Body DAkkS) for the accreditation of calibration laboratories. The accredited calibration laboratories are accredited and monitored by the DAkkS as the legal successor to the DKD. They carry out calibrations of measuring devices and measuring standards for parameters and measurement ranges stipulated in the accreditation. The calibration certificates issued by them are proof of traceability to national standards, as required by the ISO 9000 and ISO/IEC 17025 family of standards.

Source: Guidelines DKD-L 4-1 Test value uncertainty in the compliance assessment, edition of 04/2024, Revision 0, German Metrology Institute, Brunswick and Berlin. DOI: 10.7795/550.20240412

The smallest measurement uncertainty possible can be found in the DAkkS accreditation certificates of DKD calibration laboratories. The laboratory must not provide smaller measurement uncertainties for accreditation. The smallest available measurement uncertainty forms a benchmark for the performance of a laboratory.

The DAkkS accreditation of the calibration laboratory of JENOPTIK Industrial Metrology Germany GmbH demonstrates the following smallest possible measurement uncertainties:

• 12 nm
• 0.012 µm
• 0.000012 mm
• 0.000000012 m

That is 12,500 times smaller that the diameter of a human hair.

The regulations for the length of validity of a DAkkS accreditation have changed several times over the years. Since the judgment of the German federal administrative court (BVerwG) on the time limit of accreditations of 19 September 2018, accreditation certificates are issued without a time limit. They retain their validity until they are revoked, suspended, restricted or changed by the DAkkS, or the site renounces its accreditation.

The current status of the valid and monitored accreditation can be found in the database of accredited sites of the German Accreditation Body (www.dakks.de).

With the roughness, form, contour and shaft measuring systems from HOMMEL ETAMIC, an exceptionally wide range of parameter and characteristics can be measured. All these devices, however, have one thing in common: They measure lengths. To ensure that the values obtained with these measuring systems are also reliable and correct, they must – just like measurement means (standards) – be derived from all current quality standards (traceability).

The term traceability describes the process by which the measured value displayed by a measuring device or standard can be compared with the national standard for the measurement concerned in one or several stages. For HOMMEL ETAMIC, this means that all measuring instruments and standards must be compared with standards calibrated directly (or via several stages) by the PTB.

This ensures the connection to the International System of Units, shortened to SI (from the French: Système international d'unités). It is the unit system based on the International System of Quantities (ISQ). This was introduced in 1960 and is now the most used unit system for physical quantities in the world. To define the seven SI units (time, length, mass, temperature, etc.) as precisely as possible and to reproduce them, an attempt has been made to define all these quantities using an invariable natural constant.

JENOPTIK Industrial Metrology Germany GmbH's DAkkS accredited DKD calibration laboratory has standards for all accredited areas that have been calibrated by the PTB, and are, therefore, linked to and can be traced to the SI units via the PTB as the national metrology institute of the Federal Republic of Germany.

Example: History of the definition of "length"

• 1875 | At first, a meter was meant to be 40 millionths of the circumference of Earth
• 1889 | The Paris National Assembly ordered that a 1-meter-long rod of platinum-iridium be cast (original meter), but it was not accurate enough
• 1960 | The meter was defined as 1,650,763.73 times as the wavelength corresponding to the radiation propagated by atoms of the krypton isotope during their transition from the 5d⁵ state to their 2p¹⁰ state in a vacuum
• 1983 | A meter is defined as the distance that light travels in a vacuum in 1/299,792,458th of a second; the length is therefore defined by the natural constant of the speed of light c