Ergonomics 101 - The Ultimate Test for Fit

Ergonomics is one of those "squishy" subjects that a lot of people claim expertise about. In our role as furniture specifiers, we are often asked for our input on whether a certain chair is "ergonomic". To help us objectively determine ergonomic properties, my staff relies on the Business and Institutional Furniture Manufacturer's Association (BIFMA), Ultimate Test for Fit.

The UTFF is outlined below:

(7.1) SEAT HEIGHT

Users should be able to sit with their feet comfortably on the floor or footrest without undue pressure on the underside of the thighs. The thigh-to-torso angle should not be less than 90°.

(7.2) SEAT DEPTH

Users should be able to sit in the chair without undue pressure against the back of the knees, their back properly supported by the backrest and with adequate buttock and thigh support.

(7.3) SEAT WIDTH

The seat should be wider than the hip breadth of the user with allowance for movement and clothing. The seat width should not limit the ability to use the armrests comfortably.

(7.4) SEAT PAN ANGLE

This should allow users to support their feet on the floor or footrest. They should not cause the user’s torso-to-thigh angle to be less than 90°. Forward seat pan angles should not cause users to shift excessive weight to their feet or experience the sensation of sliding out of the chair.

(7.5) BACK SUPPORT

(7.5.1) SEAT BACKREST HEIGHT

All backrests should provide adequate lumbar support and buttocks clearance. For tasks requiring upper body mobility, the backrest should not interfere with the user’s movement. For users who prefer reclining postures or greater upper back support, the back height should provide support for the shoulder blades.

(7.5.2) BACKREST WIDTH

The width of the backrest should provide adequate support for the curvature of the user’s back without causing localized pressure points.

(7.5.3) LUMBAR SUPPORT

The height and shape of the lumbar support should coincide with the lumbar curve (“the small”) of the user’s back. The support should be firm, but not cause localized pressure points.

(7.6) MOVEMENTS OF THE SEAT PAN AND BACK SUPPORT

The user should be able to sit in a position where the torso-to-thigh angle is equal to or greater than 90°. The seat and backrest angles should accommodate the varying postures assumed by the user throughout the day.

(7.7) ARM SUPPORT

(7.7.1) ARMREST HEIGHT

This should allow users to sit in a variety of postures while supporting their forearms and/or elbows in a manner that avoids lifting the shoulders (armrests too high) or leaning to the side to reach the armrest (armrests too low). The armrest height should allow accessibility to, and performance of, tasks.

(7.7.2) ARMREST LENGTH

The length of the armrest should allow users to sit close enough to the work surface to perform their tasks while maintaining contact with the backrest.

(7.7.3) INSIDE DISTANCE BETWEEN ARMRESTS

Armrests should allow users to sit in a variety of postures while supporting their forearms in a manner that avoids lifting the shoulders and/or excessive outward positioning of the elbows. Armrests should allow accessibility to, and performance of, tasks. The inside distance between the armrests should allow the user to enter and exit the chair easily. The hips should comfortably fit between the armrests or supports.

For more information on seating ergonomics, visit Office Master's Ergonomic University.

Workstation Ergonomics - Read this to be comfortable at work...

On a Friday - something to make everyone a bit more comfortable in their workstation (regardless of whether it is a private office or cubicle). Full disclosure, I am a rabid convert after I set my own work area up (see HERE for the post about what I won't give up in my office).

The below guidelines are courtesy of Workrite Ergonomics  click HERE for a link to the complete ergonomics page, including a video on setting up an ergonomic work area:

Slouching, slumping or bending forward at the waist in a chair can lead to discomfort, fatigue and backache. Follow these guidelines to help prevent problems from occurring when sitting at your workstation.

A.Adjust seat height, thighs should be approximately parallel to the floor. Seat pan short enough (front to back) for knee clearance and with a waterfall front edge.

B.Adjustable back rest to accommodate the normal curve of the lower spine.

C.Articulating monitor arm supporting flat panel display. Top one-third of the screen at or below eye level; distance from operator a minimum of 18", typically at arm's length.

D.Elbow relaxed. Lower arm open at least 90°-100° to upper arm with keyboard platform set at 0°-6° negative tilt.

E.Wrists should be a natural extension of the forearm, not angled up or down.

F.Keyboard flat at elbow level with palm rest to support hands during rest.

G.Feet resting firmly on the floor; footrest needed if feet are not supported by the floor.

H.Document holder in line with front of monitor. Height and angle adjusted for the comfort of the user.

Ergonomics of Office Seating

Of all the products and services we offer, providing the proper chair is probably the most important in terms of worker comfort. With that in mind, we are providing a basic primer on seating ergonomics, specifically a visual terms sheet for the functions of a chair.

This information is provided by Office Master. To view Office Master's Ergonomics University, you can click (HERE):

Graphics Courtesy of Office Master: Source Document Click (HERE)

Basic Workstation Ergonomics

Workstation ergonomics (whether you work at a desk, a cube, or other) is critical to establishing and maintaining a healthy and productive work place. Below is a basic primer on office ergonomics, (thank you to Office Master, one of the leading producers of Ergonomic Office Seating for providing the graphics and information).

1. Monitor Height - Place top edge of screen at eye level. - This can be achieved using an adjustable monitor arm, or monitor stand.

2. Wrist Postures - Keep wrists flat with little or no bending. This can be achieved using an adjustable keyboard platform.

3. Mouse Placement -Place at same level of keyboard and as close to sides as possible. See #2 above - a proper keyboard platform will have a "mousing area".

4. Thigh Position - Keep thighs parallel to floor. An well designed ergonomic office chair will have a "seat slider", which allows the depth of the seat to be independently adjusted (to accommodate for shorter or taller users).

5. Document Holder - Place document at same level as monitor. Avoids neck strain - a document or "paper-holder" can integrate into the monitor stand in #1 above, or can be a separate piece of equipment.

6. Feet Position - Place feet flat on floor or footboard. This one gets tricky, because if shorter users adjust the height of their chair lower, it can throw off monitor height and keyboard position. A "foot-rest" can be used to achieve this position.

7. Monitor Distance - Keep at proper distance for screen size. Back to the adjustable monitor arm (which is one of my favorite pieces of technology in my office!).

Office Master provides more ergonomic information at their on-line Ergonomic University.