Safety and warning information in technical documentation

The topic of safety plays a significant role in every manual. But what does practical implementation look like? What exactly is safety-related information, for example safety instructions or warnings, and how can technical writers develop it in the first place? Legislators issue guidelines and regulations requiring manufacturers to warn users and operators of hazards. These are hazards that may arise even in situations where the product is being handled in the normal way. Technical writers identify the hazards in the risk analysis and incorporate them into the technical documentation. They also warn of residual hazards and incorrect operation in the technical documentation.

What is safety-related information?

The manufacturer must warn the user directly, for example by providing information in the user guide or by placing warnings on the machine. The types of warnings provided consist of safety information, warnings, product safety labels and/or safety symbols.

Safety information

Safety information is located at the beginning of the user guide in a separate section with a clear heading, such as “Safety”. In terms of content, this section must provide information concerning the safe use of the product. Information is given about any hazards, and how users can avoid these hazards. The safety section in the user guide also informs users of the consequences, if no action is taken to avoid the hazards.

Warning information

Technical writers place the warning information in the context in which the hazard occurs. Warning information does not contain any instructions, but is provided as a supplement to an instruction manual for example. Warning information is formulated succinctly and set out in an obvious and consistent manner.

Product safety label

In the case of complex technical information, it is helpful if the warning and safety information is also displayed or stated on the product. Users at risk should be able to see and recognise warning and safety information at all times during use and at the correct time.

US standard ANSI Z535 - safety-related information with signal words and a logical structure

ANSI Z535.6 conformity with signal words in warning and safety information was originally developed for the American market. Warning signs located on the product, follow the US standard ANSI Z535.4. The European market has adopted the compliant signal words and the standardised structure.

Signal words

  • Danger
  • Warning
  • Caution
  • Notice

Using the signal words, you can classify the warning or safety information. Each signal word, a certain RGB-colour is assigned.

Warning and safety information is constructed in three parts.

In each guideline, the following information should be given:

  • Type of hazard and source of hazard
  • Consequences in the event of non-compliance with the guideline
  • Measures to avoid hazards

Safety and warning information in practice

How do technical writers know with certainty where the warning information must be located in the user guide? As part of the process that is required in order for the product to be awarded the CE mark, constructors and developers draw up a risk analysis. In the risk analysis, developers record the points at which users are exposed to a residual hazard and the points at which users must be warned of that hazard by providing a suitable warning in the user guide. Developers also classify the severity of the hazard. The development department and technical writers therefore work side by side.


Correctly implementing safety information and warnings in four steps:

  • Classify the safety information or warning using the signal word
  • Select the appropriate symbol that will be used consistently in all safety information and warnings.
  • Describe the hazard, the possible consequences and what users can do to avoid the hazard.
  • Compose understandable texts - use simple words, avoid passive constructions and use a positive formulation.