Simplified Technical English

Developed for precision and accuracy, Simplified Technical English helps keep us safe by preventing ambiguity in technical manuals, adopted across industries worldwide

The international language of many industries is English, and English is the language most used for writing technical documentation. However, it is often not the native language of the readers (or even of the authors) of such documentation. Many readers have limited knowledge of English, and are easily confused by complex sentence structures and by the number of meanings and synonyms which English words can have.

ASD-STE100 (Simplified Technical English, or STE) is a controlled natural language developed in the early eighties (as AECMA Simplified English) to help the users of English-language maintenance documentation understand what they read. It was initially applicable to commercial aviation. Then, it became also a requirement for defence projects, including land and sea vehicles. As a consequence, today, primary texts of maintenance manuals are mostly written in STE.

STE was originally developed during the 1980s by ASD’s predecessor, the European Association of Aerospace Industries (AECMA) at the request of the European airline industry. While Simplified Technical English was initially developed for commercial aviation, it has since been adopted by other industries, and is used widely internationally as a global standard to improve the comprehensibility, consistency, and translatability of technical documentation.

What are the benefits of Simplified Technical English?

  • STE improves the readability of technical documents, making it easier for users to follow and apply;
  • STE reduces the risk of errors, misunderstandings, and accidents, enhancing the safety and quality of technical operations;
  • STE makes it easier to translate technical documentation into other languages; promotes the standardisation and harmonisation of technical terminology across different industries and countries, improving the communication and collaboration.

ASD-STE100 is maintained by the Simplified Technical English Maintenance Group (STEMG), a working group of ASD.

What are the basics of Simplified Technical English?

Simplified Technical English consists of a limited (controlled) vocabulary and restricted writing rules. It has very limited scope for creativity due to its rules, which are designed to achieve clarity in technical documents such as manuals and instructio...
Learn more

Download ASD-STE100

To download the latest ASD-STE100 Issue 9, please visit the official ASD-STE100 website's Downloads page. There, you can request a free copy by following the instructions

Get your copy

STE Maintenance Group

ASD-STE100 is maintained by the Simplified Technical English Maintenance Group (STEMG), a working group of ASD. 
Learn more

ASD-certified courses on STE

UniNettuno University in Rome has a memorandum of understanding with ASD to provide ASD-certified online computer-based training for Simplified Technical English

Learn more

Contact