A Guide to Simplified Technical English: Improving Your Technical Documentation

What’s Simplified Technical English?

Simplified Technical English, STE in short, is a writing standard commonly used in technical writing. It consists of two basic parts, the STE dictionary and writing rules.

The STE dictionary

The STE dictionary lists approved English words and their definitions. Also, it refers to non-approved words, referring to an approved alternative. Here’s an example (source):

1. Keyword (part of speech): accessible (adj)
2. Approved meaning/ALTERNATIVES: ACCESS (n)
3. APPROVED EXAMPLE: TURN THE COVER UNTIL YOU CAN GET ACCESS TO THE JACKS THAT HAVE “+” AND “-” MARKS.
4. Not approved: Rotate the cover until the jacks marked by + and – are accessible.

Technical writers who follow the STE dictionary must use approved words for specific concepts. Each organization can add their own technical names and verbs to the basic dictionary.

Writing rules

The current ASD-STE100 Issue 8 contains 53 writing rules which cover different aspects of grammar and style. Their overall aim is to increase clarity and reduce ambiguity.

For example, verbal phrases with “-ing” aren’t allowed in Simplified Technical English, as they can be confusing, especially for people whose native language isn’t English. Also, technical documents should contain short sentences only, with a maximum of 20 words for a procedure or 25 words in a description. (Source)

What’s a controlled natural language?

The Simplified Technical English standard is often referred to as a controlled language or controlled natural language. Controlled languages are a subset of a particular natural language, which is typically defined via rules and dictionaries.

There are two types of controlled languages:

• The proscriptive approach: The controlled language’s specifications define which language characteristics aren’t allowed. Then, the controlled language is basically natural language, minus the grammatical, stylistic, and terminological restrictions outlined in the standard.
• The prescriptive approach: These specifications list rules and terminology technical writers need to follow. Unapproved words or sentences that don’t follow the specified rules aren’t allowed.

ASD-STE100 follows a prescriptive approach: It clearly defines rules for simplified English and provides a list of approved words and how to use them.

What’s the origin of the Simplified Technical English standard?

As mentioned above, you can refer to ASD-STE100 as a writing standard and controlled language, which enables technical writers to create clear, concise, and unambiguous technical documentation. While originally developed in the aerospace industry, nowadays the STE standard is used in many other industries with a focus on high precision and safety, such as defense or manufacturing.

The English language is often described as an international language that’s used as a professional communication language across industries. Nevertheless, many readers with limited knowledge of the English language struggle with understanding it correctly, when it comes to complex and highly technical documents.

To address the challenges of multilingual readers working with complex aircraft maintenance documentation, the European Association of Aerospace Manufacturers (AECMA), developed the AECMA Simplified English standard during the late 1970s and early 1980s. No, the AECMA is known as the Aerospace and Defense Industries Association of Europe (ASD).

The goal: Eliminating misinterpretations caused by ambiguous and unclear language, to make sure every reader could understand maintenance aerospace maintenance manuals and technical guides, regardless of their first language.

To achieve this goal, the standard contained a limited vocabulary and rules that aim for instance at shortening the sentence length or prohibiting overly complex English grammar.

AECMA officially released the first version of the STE guidelines in 1986 under the name “AECMA Document, PSC-85-16598”. (Source)

In 2005, with the restructuring of AECMA into ASD, the standard was renamed ASD-STE100. From its foundation since then, there have been several updates to the standards to address technological development and the needs of users working with ASD-STE100 in many industries.

Why use Simplified Technical English in tech writing?

Simplified Technical English is required by industry standards

There are aerospace industry standards which require the use of Simplified Technical English. Also, several industry associations require or recommend using the standard when writing technical documentation. (Source)

Examples include:

• Standards which require the use of Simplified Technical English:
  • ATA Specification i2200
  • ATA104
  • S1000D
• Organizations which recommend Simplified Technical English or make it a requirement for specific document types:
  • The European Defence Standards Reference (EDSTAR)
  • EASA (European Union Aviation Safety Agency),
  • FAA (Federal Aviation Administration)
  • CAAC (Civil Aviation Administration of China)

Besides being a requirement or recommendation for technical documents in aerospace and defense, ASD Simplified Technical English offers multiple benefits for all kinds of technical documentation, which we’ll explore next.

It improves clarity, readability, and consistency

Using STE for technical writing improves the quality of your technical documents drastically. It makes your technical documentation clearer and more accessible for readers native in other languages than English.

Let’s look at clarity, readability, and consistency in more detail:

• Improved clarity: STE eliminates ambiguity, making sure users can quickly understand instructions or specifications.
• Better readability: Both a restricted vocabulary and a simplified grammar make technical writing easier to read and process. This way, documentation is more accessible for non-native English speakers.
• Consistent terminology: STE standardizes terminology by defining approved words and how they’re used with their specified meaning. Fewer term variants mean more consistency, making technical information clearer and avoiding reader confusion.

Misunderstandings caused by unclear documentation can have tragic consequences in industries like aerospace and defense. And even if product misuse because of misunderstandings doesn’t have life-threatening consequences, it’s a serious issue for enterprises. Think of the increasing numbers of support tickets or product recalls.

The solution: Using standardized, clear technical English in copy like safety instructions and descriptive writing. This way, organizations not only improve customer satisfaction but also reduce operational costs, enabling a more efficient and scalable support process.

How to implement STE into your technical content writing

In the following, you’ll learn how to incorporate ASD Simplified Technical English into your technical writing processes:

Familiarize yourself with the standard

The first step is to familiarize yourself with the STE specification. Request your own copy of the newest ASD-STE100 issue and read it to understand its structure and get into the flow of simplified technical language.

Add Simplified Technical English to your style guides

Now it’s time to integrate the Simplified Technical English writing rules into your own style guide. There might be contradictions between your company’s writing standards and Simplified Technical English.

Whenever regulations require full adherence, don’t alter the STE guidelines — except for adding technical names that are unique to your organizations to the dictionary.

If not officially required, you can consider fine-tuning your guidelines, to be able to seamlessly add them to your existing writing standards. And don’t forget to encompass the STE dictionary into your efforts.

Now, the not-so-simple question is: How to remember the rules and words while writing technical documentation?

Consider ASD Simplified Technical English training

The Simplified Technical English Maintenance Group (STEMG) strongly recommends you undergo training before starting to use ASD STE100 (source). These trainings give you the chance to internalize the rules better, compared to “just reading” the standard.

Nevertheless, writing in a controlled language can be challenging. That’s why supporting tools have always been present in the history of Simplified Technical English.

Use Simplified Technical English tools

Four years after the release of the first ASD STE100 issue, Boeing released its Boeing Simplified English Checker.

Other tools followed to meet the growing demand for simplified English checking that goes beyond Boeing, and beyond the aerospace industry in general.

Did you know that Acrolinx fully supports Simplified Technical English? This means you can use our content governance software as your STE checker, too. And this is how it works:

1. When you build your style guide with Acrolinx, you can select Simplified Technical English as your language of choice.
2. Then you can choose whether you need compliance with issue 6, 7, or 8, and whether you want to check against the STE dictionary — or not.
3. You have the possibility to fine-tune your style guide.

After setting up your STE guidelines, your writers receive guidance directly in the tools they use for technical documentation.

Whenever they use unapproved words or violate a Simplified Technical English rule, Acrolinx notifies them and offers advice and suggestions to ensure alignment with the standard.

Simplify your technical documentation with Acrolinx

Ensuring compliance with STE guidelines can be challenging, especially when multiple technical writing experts contribute to documentation projects under high time pressure.

Acrolinx simplifies STE compliance through automation, and by providing immediate guidance to technical writers. By integrating STE rules and dictionary into its content governance platform, Acrolinx not only checks for compliance but also suggests approved alternatives, helping writers follow the ASD-STE100 standard without interrupting their workflow. 

Using automation capabilities, you can also use Acrolinx to ensure standard compliance across content repositories, or embed the checking into your publication workflows. This way, your documentation remains compliant at every stage of your content supply chain.

Ready to make your technical documentation clear, concise, and compliant? Acrolinx is here to help. Watch our biweekly product webinar to learn how.