ASD-STE100 Simplified Technical English FAQ Home // ASD-STE100 Simplified Technical English FAQ



ASD-STE100 Simplified Technical English

– the standard for accurate & efficient documentation

Frequently Asked Questions



1. The who, what, why and how of ASD-STE100

STE is an international standard that helps to make technical documentation easy to understand. It includes a set of approximately 53 technical writing rules and a basic general vocabulary dictionary of approximately 900 approved words for writing technical documentation. STE helps you:

  • Write clear and translatable documentation for a global audience
  • Save costs for your documentation processes
  • Achieve consistency across all documentation types
  • Minimise maintenance errors and lower human factors risks

The writing rules regulate the use of words, layout, sentence length, and how to write warnings, cautions and notes. The dictionary includes general words that you need to make sentences.

Besides general words in the dictionary, technical writers can also use company-specific terms when writing. These unique terms are classified as Technical Names and Technical Verbs. STE does not restrict the use of these terms. Instead, STE rules help the writer decide if a word qualifies as a Technical Name or a Technical Verb. In this way, companies still have the final say on defining their preferences for their corporate terminology.

STE is no longer a new concept. STE history dates back to the 1930s when Basic English was introduced, and in the 1970s when Caterpillar first used controlled English in the form of Caterpillar Fundamental English (CFE).

The STE project officially commenced in 1979 when there were far more aircraft manufacturers than there are today. Although everyone wrote in English and worked according to the same ATA Specification (known as ATA 100 at the time, Air Transport Association of America, today known as Airlines for America, A4A), writing styles were markedly differently and therefore highly unregulated. As a workaround, some European airlines translated parts of their maintenance documentation into their local language so that their maintenance personnel could understand and carry out their work tasks.

The growing complexity of documentation and increasing proportion of non-native English speakers in the aerospace & defence called for the need of a technical writing standard.

STE addresses difficulties in understanding the English language. Problems related to complex sentence structures, confusing word forms, and unclear vocabulary are identified and resolved using STE technical writing rules.

STE was originally created for the aerospace industry. Initially, it was applicable to commercial aviation, and subsequently became a requirement for military projects. However, the benefits of STE have proven very highly applicable to all industries. This is why 60% of our STE customers today come from industries outside of aerospace & defence.

ASD-STE100 often is a requirement for aerospace and defence projects, so there are many users in these industries for compliance reasons. A roughly equal number of companies outside these industries use STE, mainly to save translation cost and improve translation quality and consistency.

STE users include the following:

  • Compliance managers
  • Customer support managers
  • Documentation managers
  • Editors
  • Engineering managers
  • Engineers and SMEs who create documentation
  • ILS managers
  • Maintenance managers
  • Operation managers
  • Product managers
  • Project managers
  • Quality managers
  • Safety managers
  • Technical writers
  • Translation managers
  • Translators

Although STE was designed to make it easier for readers to more easily understand technical documentation, we at Shufrans TechDocs found that writers with English as a second language also benefit from the guidance given in the ASD-STE100 specification, and especially hands-on training.

No, STE is a controlled language specification that should be used by native and non-native speakers of the English language to promote responsible and unambiguous technical writing practices and clarity in technical content for mutual benefit.

The main difference between STE and the average corporate style guide thus is the addition of general vocabulary, while providing for flexibility regarding company- and industry-specific terminology – a very powerful concept that greatly facilitates adaptation to a company’s specific requirements.

As STE was developed by people from different companies (including for example Boeing and Airbus), countries (USA, Canada, various European countries) and professional background (writers, linguists and engineers), the rule set and vocabulary are rather well-balanced rather than to reflect the views of a single person or company. Moreover, the rules and vocabulary were validated against actual content from relevant manuals.

Since development of the specification started some 30 years ago, it has seen regular updates, in part based on change requests from users in the field. The current release is Issue 7, released in January 2017. The specification is maintained by ASD (formerly AECMA), the AeroSpace and Defence Industries Association of Europe.

2. Training services & software checker tools

No it isn’t, as long as you allow for adequate training by a professional trainer with practical experience, such as our Ms Shumin Chen. Look or ask for relevant testimonials from people in an industry relevant to you. You could also ask the intended trainers to rewrite a sample piece of text (half a page or so) for you.

Shufrans TechDocs is the global leader in STE training and consultancy. We offer the following certified STE training programmes:

  • Customised training workshops conducted on-site
  • Open STE training classes on a per-seat basis. Ideal for small and medium-sized companies.
  • Post training support to facilitate any ongoing STE implementation process

You must have a good technical knowledge of the subject of your writing.

  • A clear and in-depth understanding of the STE writing rules and its dictionary.
  • Trained personnel can identify which words they can use as Technical Names and Technical Verbs.
  • Technical writers will be able to structure thoughts and ideas logically and understand their reader’s needs.

No, in most cases there is no need for this. Training, although only around 10-15 percent of the cost of such supposed “full implementation”, achieves 75% of the benefits and results of a training-only approach. If you want more, we recommend having a custom Technical Name and Technical Verbs dictionary built, which will further improve results. Refer to our page on Terminology Management for more information.

Software without proper training, however, will do more harm than good. A disciplined and well-trained writer does not need checker software.

Yes. Shufrans TechDocs is the authorised reseller for Acrolinx – a flexible checker that supports writers in all industries to write in Simplified Technical English. Acrolinx integrates with: Microsoft Word, Adobe FrameMaker, Adobe InDesign, Adobe CQ, Arbortext Editor, XMetal, oXygen and Serna. Refer to our page on acrolinx STE for more information.

Yes, if the readers already have a basic knowledge of English.

Yes, absolutely. Although STE was created to improve maintenance documentation, its key principles can dramatically improve the reading quality of documents in any industry. Only 7% of the current STE content is related to aerospace, while 93% is applicable to all contexts without the need for adaptation.

3. Let’s try to simplify the rules for you

Rules regulate the choice and use of words, building phrases and sentences, the use of articles, the verb tenses that can be used and (to some extent) the punctuation. Some of the rules are specific to procedural or to descriptive text. Part of the rules is generally known to professional communicators, but the overall set is in general rather nicely balanced while going beyond most corporate and general style guides.

  • Keep procedural sentences as short as possible (20 words maximum).
  • In an instruction, write the verb in the imperative (“command”) form.
  • Keep sentences in descriptive writing as short as possible (25 words maximum).
  • Start a warning or a caution with a simple and clear command.

Each rule comes with an often lengthy explanation.

If we could only pick one rule that has a lot of positive impact on readability and re-use, it would be rule 1.1, which basically tells us that we can only use approved words (yes, that’s right –every single word we use has to be approved), and that these words can come from three sources: the general approve vocabulary listed in the specification, Technical Names and Technical Verbs. The latter two are determined by the user, based on industry, company and product.

4. A general vocabulary dictionary used across industries

The STE dictionary consists of a general vocabulary with sufficient words to write any technical sentence. However, the dictionary does not include Technical Names and Technical Verbs which are applicable to specific projects or industry.

We use words from the STE dictionary to form basic sentence structures. In the case of company-specific terminology, we must refer to the writing rules for recommendations and guidance related to selecting Technical Names, Technical Verbs, and their associated categories.

Approved words in the general vocabulary dictionary are always simple, flexible and commonly used. As an example, the verb “do” is simpler than alternatives such as “achieve”, “carry out”, or “accomplish”.

In many cases, the general words that are approved have only one approved meaning and one part of speech. For example, “about” has only one approved meaning “concerned with”. In STE, you cannot use “about” to mean “approximately” or “around”. These words are approved but defined differently in the dictionary. In another instance, “check” is only approved as a noun, as in “do a check”, not as a verb, as in “check the lights”.

Yes. Technical Names and Technical Verbs are not listed in the dictionary. Instead, they are defined in the specification by the categories they belong to. If an unapproved word in the dictionary is used as part of a Technical Name or Technical Verb, it becomes acceptable to use it.

5. How do I get started?

Send us a sample of your existing documentation. Our trained STE editors will analyse and re-write part of your document to demonstrate the benefits of Simplified Technical English.
Contact Shufrans TechDocs at to set up a teleconference meeting with you and your team members.

Use this opportunity to verify rewritten samples and clarify with our experts about the STE writing rules that have been applied in the context of your business.

Through a combination of classroom training, hands-on written exercises, and rewriting workshop, our principal ASD-STE100 trainer Ms Shumin Chen will teach participants how to correctly and effectively use STE in practice. She will also address some of the mistakes commonly found in technical writing and the frequently incorrect use of common STE writing rules.

Customised training workshops Open STE training classes Post training support
  • Conducted on-site for a minimum group size of 5
  • 2-3 day STE training workshop
  • Tailored to your specific requirements
  • Per-seat basis
  • 2-day STE training workshop
  • Ideal for small and medium-sized companies
  • STE expert on-site attachment
  • Up to 4 weeks
  • Facilitate any ongoing STE implementation process.


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