Human Factors

Human factors (or ergonomics) is the study of interactions between people and the things they use. It's possible to design healthy, comfortable, efficient objects and workspaces only if human factors are well considered.

In 2007 I conducted a human factors evaluation of a conference room for a Warsaw-based pharma company. I identified key conflicts between architecture, equipment, and the users, and made recommendations for human factors improvements.

Dummy human CAD figures, from female 5th percentile to male 95th percentile

There is a lot of tools for designing with human factors in mind. I created 1:10 human dummy CAD figures: the 5th, 50th and 95th percentile of female and male population in Poland. I used two outmost dummies (female 5th and male 95th percentile) in this project. Designs that are suitable for both these extreme sizes will also be suitable for the majority of the population.

This is what the company's conference room looked like at the outset of my human factors evaluation (some user–equipment conflicts already obvious).

Photographic documentation of the conference room
Photographic documentation of the conference room
Photographic documentation of the conference room
Photographic documentation of the conference room
Photographic documentation of the conference room
Photographic documentation of the conference room

This is what the company's conference room looked like at the outset of my human factors evaluation (some user–equipment conflicts already obvious).

I took measurements of the room's interior and furniture, analysed most popular communication routes, and measured users' positions when performing usual office tasks.

Diagram of the conference room, top view, measurements Diagram of the conference room, top view, walking routes Diagram of the conference room, top view, lines of sight

I used the dummy human figures to test furniture dimensions, best locations for equipment, and optimal positioning of wall fittings and door handles.

Diagram of the conference room, side view, measurements Diagram of the conference room, side view, using installations

I used the dummy human figures to test furniture dimensions, best locations for equipment, and optimal positioning of wall fittings and door handles.

People have unique shapes and sizes. Yet, mass-produced office chairs usually come in one size to fit all. In my human factors evaluation I checked chair suitability for users larger than female 5th percentile and smaller than male 95th percentile.

Sitting is a dynamic activity, so I also took into account various positions in which people sit during a meeting.

Analysis of sitting positions Analysis of sitting positions: users leaned back Analysis of sitting positions: users leaned forward

Eight modular tables used in the conference room can be arranged to sit 14 people. I used anthropometric tables by Henry Dreyfuss Associates to evaluate user comfort zones and find work area conflicts in possible sitting configurations.

Analysis of desk workspace: one user Analysis of desk workspace: two users Analysis of desk workspace: three users

I recommended following changes to improve the ergonomics of seatings:

  • Reduce seatings's depth to allow users to sit deeper for better lumbar support,
  • Improve seating's front-edge profile and decrease seating's height to remove pressure on users' lower thigh arteries,
  • Reduce table top's thickness to allow chairs to be moved fully underneath it.
Recommendations to improve the ergonomics of seating

Other human factors recommendations included:

  • Increase table width to aviod conflicts between users' working areas,
  • Move doorway entrance to the corner of the room to avoid clashes with the table,
  • Switch the doorwar to open outward to meet fire safety guidelines,
  • Mount all electricity/media installations at min. 75cm to improve accessibility for taller users,
Recommendations to improve the ergonomics of access areas in the conference room

I was recently contacted by a retired boat designer who is building a support device for disabled people. He needed the male 95th percentile CAD dummy to use in his drawings and scale prototyping. I was really happy to share my CAD dummies with him. The file is available to everyone here.

Dummy human CAD file