ISO 11240

ISO 11240 – Units of Measurement

What ISO 11240 does:

  • specifies rules for the usage of units of measurement for IDMP
  • specifies requirements for traceability to metrological standards
  • establish reference code system for units
  • provide structures and rules for mapping between different unit vocabularies and language translations
  • linking to existing systems, dictionaries, and repositories

Strength of a medicinal product based on ISO 11240

In the case of strength given on a per dose basis, additional information on the characteristics of the countable dose item
may be required when comparing to strengths of other products.

EXAMPLE 1 Expression “per dose”: Total amount of substance per total amount of solution (200 mg of substance
contained in 10 ml of solution), total mass of ingredient contained in one single dose (500 mg of substance contained in
one tablet). Note that the description of the component (substance, solution, tablet) is not part of the unit of measurement.

EXAMPLE 2 Expression as intensive quantity: Mass concentration 20 mg/ml, activity content 5,000 IU/g.

EXAMPLE 3 Using the unit symbol “U”
The unit “U” of enzymatic activity was defined in 1964 by the International Union of Biochemistry as the
catalytic activity that catalyses the transformation of 1 µmol of the substrate per minute. Typical biological
enzyme activities are in the range of 1 U to 100 U. This unit of measurement can also be expressed explicitly
as “µmol/min”, where enzymatic activity is the property being addressed. Still, some arbitrariness is involved in
the definition of “standard conditions” (e.g. temperature, pH).

This unit denoted by the symbol “U” is not an arbitrary unit. In order to ensure traceability and avoid ambiguities,
it is important to discriminate this meaning against the frequently encountered usage of the same symbol “U”
for other (arbitrary) units. This is especially required to ensure unique meaning of codes used for information
exchange. “U” is assigned to enzymatic activity in the UCUM code system. However, the following description
uses the symbol “U” for a completely unrelated concept. Here “U” stands for an arbitrary unit that is defined
based on a “bioassay”:

e.g. Concentration 5 000 U/ml solution for injection.

Mapping between different unit vocabularies and language translations

ISO 11240 mapping table

ISO 11240 mapping table


SPOR Data Mapping Activities

RMS & OMS Mapping – Impact to Industry

Concerning SPOR Data Mapping Activities the Industry is invited to start now with mapping activities. At the same time be aware, that the RMS and OMS lists are still worked on.

The preparing activities are:

  • SPOR Programme participation & Engagement via SPOR Change Liaisons (IDMP1)
  • Analyse / adapt process to keep data synchronised
  • RMS mapping
  • OMS mapping
  • Synchronise local data with SPOR
  • Request new/updated data prior to regulatory submission
wiki spor data mapping process

How to get access to RMS data

Before RMS go-live

Industry in SPOR Data Mapping Activities does not have access to EUTCT so CSV lists are made available here in the IDMP1 Website.

After RMS go-live

Stakeholders can log on to RMS, browse and download a CSV or XML file

 What data to use from RMS for mapping

  • Identifier
  • Language (En & other languages)
  • Term Name
  • Short Name
  • Description
  • Status
    Provisional – When a Term is created after validation by the EMA Data Steward but prior to approval by the List Owner. The full detail of this Term is visible to all users.
    Current – When a Term is approved by the List Owner for use in new applications/records.
    Nullified – When a Term has been published in error and needs to be removed.
    Non-Current – When a Term is not approved by the List Owner for use in new applications/records and/or refers to legacy data. See also Current Term which contains the indication of the current term(s) that should be used instead.
  • Domain
    Human (H), Veterinary (V), H&V (Human & Veterinary)

Mapping/Matching Referentials data

Matching the following data elements between the RMS list and your data set (manually or using IDMP1 match tool)

wiki spor rms oms mapping


Complete the data in your systems with RMS to facilitate automatic updates/sync.

The mapping exercise enables identification of new/updated terms and preparation for data synchronisation.

You only need the Term ID (and version?)
BUT consider including all/some of the above elements in your database in order to automate the comparisons/synchronisation

There is no requirement to cover translations at this stage.

When to request a change

  1. New Local Term – Term exists in your List but not in RMS
  2. Updated RMS Term – Term exists in RMS and your List, but with some differences

Where to request a change

RMS – please submit your change request (on the English version and main data attributes only) to RMS when it goes live

Synchronisation approach

Decide your synchronisation approach

wiki spor rms oms mapping 3

Download IDMP SPOR Referentials EUTCT (ZIP)

    IDMP Wiki


    UCUM is the short form of the Unified Code for Units of Measure – by the Regenstrief Institute. It  is a system of codes for unambiguously representing measurement units to both humans and machines.

    Systems and Standards (Courtesy of Thomas Balzer (BfArM Germany) – 21.07.2015)
    • International System of Units (French: Système International d’Unités, SI)
    • UCUM sets up rules how to transform units to a machine readable form
    • ISO 11240 shows how to implement a system according to UCUM
    • Referentials: a value set of Units for Measurements regarding ISO 11240 and UCUM
    • Copyright: Regenstrief Institute and „Unified Code for Units of Measure”
    • Board of Advisors: Dr. Simon Cox, Dr. Christof Gessner, Dr. Gunther Schadow, Dr. Daniel Vreeman, NLM Liaison: Dr. Clement J. McDonald
    • Specification:
    Ownership of Dictionary (Courtesy of Thomas Balzer (BfArM Germany) – 21.07.2015)
    • For SI it is the General Conference on Weights and Measures (CGPM)?
    • For UCUM it is the Regenstrief Institute and UNITSOFMEASURE
    • For ISO 11240 it is ISO
    • For a Value Set it is the European Union Network Data Board (EUNDB)
    Copyright and License Terms of Use (Courtesy of Thomas Balzer (BfArM Germany) – 21.07.2015)


    Permission is hereby granted in perpetuity, without payment of license fees or royalties, to use, copy, or distribute the UCUM codes, UCUM Specification, and UCUM table (in all formats in which it is distributed by The Organization and the UCUM Organization) (collectively, the “Licensed Materials”) for any commercial or non-commercial purpose, subject to the following terms and conditions:…

    Articles on UCUM

    Value sets


    UOMo adds Units of Measurement support for IT Systems and Services both to Language and Data.