Hannes Sacher
Human Essentials GmbH
Human Factors Engineering / Usability Engineering​
Hannes Sacher
Human Essentials GmbH
Formative Usability Evaluation​
Hannes Sacher
Human Essentials GmbH
Use Related Risk Analysis​

Human Essentials -

this stands for honest commitment and well-founded tools along the entire usability engineering cycle, at the center of which is the human being as the user.

Together with you, we facilitate all development processes of new products or digital solutions along relevant usability standards.

With both my technical and work psychology background, and as a trained human factors engineer, it is clear to me that understanding the customer is the most important component for entrepreneurial thinking and action. The added value is not only defined by features, but also by ingenious user-specific requirements. This needs special knowledge for elicitation, analysis and implementation which I can provide you.

As a socially competent and resilient usability expert, I offer sustainable solutions in human factors engineering. In doing so, the holistic orientation towards the needs and requirements of the users is dear to my heart. Because only what people like to use makes products and services successful. Together with you, I look at what is essential in the human-technology interaction and accompany you from the initial idea to international market approval and subsequent post-market follow-up. Because it is fundamental!

Dienstleistungen Human Essentials

My Services

Are you developing a product that needs to be effective and safe to use and furthermore successful on the market?
I know the tools, using them for you.

Human Factors Engineering / Usability Engineering

Successful development always starts with detail work, so looking closely and applying the right approach leads to the overarching goal. I have high standards when it comes to consistent usability engineering. And that is in the development of devices, software applications and systems both in medical technology and in other safety-relevant areas. Depending on your requirements I can take over all usability activities, starting from planning to project management and executing tasks or, if you wish, I can take over only certain tasks. I attach importance to a structured approach using established methods and considering the current regulatory requirements.

User Research and Requirements Engineering

A product that does not please the user runs the risk of not leading to sustainable success. Through systematic use- and user-analysis you gain clear insights into what functions and forms your product needs to have. Proven usability methods such as contextual inquiry, ethnographic studies, interviews, workshops, focus groups and surveys form the basis for innovative products.


Certainly, you and your development team already have a vision of your future product. However, in most cases such visions are distributed among individual brains as ideas and concept fragments. I support you in gathering and substantiating these ideas together with your internal stakeholders in suitable settings and aligning them with the use-related requirements. The design variants, elaborated in this step, can be transferred into design models and early prototypes.

Formative Usability Evaluation

Through systematic evaluation of your prototypes, you gain a clear understanding of which implemented functions, operating- and display-elements will work for users and therefore will either be accepted or rejected by your customers. This will help you to iteratively improve your product design in an early stage with a low budget. Additionally, I am happy to support you in deriving usability related factors from your clinical studies.

Summative Usability Validation

In close collaboration with external usability agencies (usability labs), I carry out the usability validation of your medical devices and software applications for market readiness. This creates the basis for the FDA 510(k) approval and the EU declaration of conformity (DoC).

Use Related Risk Analysis

The whole development process for medical devices follows a risk-based approach. Products that are not only easy to use but also fulfill the users’ needs, naturally reduce risks through optimal design. I support you with the use-related risk analysis as well as with the elaboration of risk mitigating factors.

Post-Market Survey

Feedback through post-market surveillance (PMS) activities of your medical products on the market can lead to design adaptation and risk reassessments. I support you in analyzing use-related issues in order to improve the usability as well as the error tolerance and the safety of your products. Furthermore, I support you with the usability related topics for the post-market clinical follow-up (PMCF).

About me

Experienced and enthusiastic human factors engineer with over 10 years of proven experience in the field of human-technology interaction for safety-related systems and organizations. Empathic, structured and with a lot of pleasure in interdisciplinary teamwork.


As a human factors engineer, I consider myself as a link between users of devices, systems or software applications on the one hand and the various stakeholders of a manufacturer on the other hand (such as product management, industrial design, software-, hardware- mechanic engineering, risk management, clinical affairs, regulatory affairs, post-market survey). I consider myself as an advocate of medical device users (such as medical doctors, nurses, patients) and in this role I succeed in transforming the user specific findings and relevant factors into the jargon of the development teams. With my holistic view of not only the user needs but also the contextual usage with respect to the use-related risks and realizability of a product, I support you in finding the optimal solution for your product.


My professional path first led me to the fields of industrial electronics as well as information technology. In the course of my work, my affinity has grown for the problem area of how to optimize human-technology interactions. I have continuously broadened and deepened my skills and obtained the following degrees.

  • Electronic Engineer HF
  • Psychologist FH (Applied work and organizational psychology)
  • Master of advanced studies MAS HCID (Human Computer Interaction Design


My practical experience is based on many years of working in the areas of

  • Field Service Engineering (imaging medicine diagnostics, MRI, CT)
  • Planning and configuration of data networks
  • Responsible person for the entire IT infrastructure of a higher school of design
  • Human Factors Engineering for industrial processing systems
  • Human Factors Engineering for nuclear power plants
  • Human Factors Engineering for medical devices


I speak fluent (business) German and English


I am happy to talk about your project.