Work Surface Height
First fit your chair, then your desk
A chair alone rarely controls how you sit. Your line of vision, the activity of your arms, and the physical demands of your particular task will influence your posture. Often, the organization and configuration of your work surface and office aids can have greater impact than a chair on your posture.
If desks, phones, and materials don't fit, you will find yourself hunching over, craning your neck forward, and straining your eyes and arms to find comfort. A poorly designed work area can be especially stressful to your neck and upper-back regions.
Consider your chair and desk as a unit; both must fit you. Determine your chair height first, then determine your work surface height.
Your
ideal desk height
Ideal work surface height is dependent upon your height, the tasks you perform, and the equipment and tools you use. Your most comfortable working height is at or around elbow height. You should be able to maintain a forearm-to-upper arm angle between 70 degrees and 135 degrees.
If your task requires some upper arm force, your work surface should be below elbow height (e.g. stapling, stamping, packing). If fine visual attention is needed, the surface should be higher (e.g. graphic, copy editing of fine type). Generally, computer users performing intensive word processing prefer lower desks - sometimes below elbow height, and those performing computer graphics and page layout activities prefer higher desks. Most people prefer a slightly higher surface for writing, and a slightly lower surface for keying.
Most work surfaces are a standard 28" to 30", a good sitting height for most people between 5'8" and 5'10" tall. If you are taller or shorter, be prepared to change your work surface height.
If your work surface or materials are too low, raise them on blocks.
If your desk or materials are too high, your should cut it down or get a better fitting desk. For work that involves no reaching (e.g., dedicated keyboard tasks without paperwork), your can raise the chair and use a footrest, or use a seat cushion.
Task
requirements for work surface height
Use the following guidelines to determine which activities are best performed seated, which are best performed standing, and when you might benefit from an adjustable workstation.
Postural variety is important for maintaining good health. Whenever possible, vary your work postures between sitting and standing. If you have enough space, set up both sitting and standing work surfaces within your work area, or use an adjustable sit-stand work surface.
SITTING HEIGHT WORK SURFACE
Use a conventional ergonomic chair or a saddle chair when ...
- Your work is light.
- Your work is within a comfortable arm reach envelope (within 38 cm or 15” of your body’s center).
- Your work is within a comfortable field of vision (less than 64 cm or 25” from the eyes).
- Your work is prolonged and offers little postural variation
STANDING HEIGHT WORK SURFACE
Work in a standing posture or in a saddle chair when ...
Your work is performed over distances that exceed your comfortable arm reach envelope (reaches more than 38 cm or 15” from the body’s center
Your work requires that you move your body along with your arms
Your work is spread out over several areas
Your work height above the floor is variable
Your work involves weighted objects or large forces
Visual needs make a seated posture inappropriate, because of difficulty in seeing something, or because you have to move around to get the best angle to view something
You need to relieve the fatigue of sitting for long periods of times. Periodically performing some tasks from a standing position can give computer operators a break from the usual sitting position
USER-ADJUSTABLE WORK SURFACE AT SITTING HEIGHT
A sitting height desk that you can adjust up or down a few inches is good when...
- You need to relieve the fatigue of sitting for long periods of times during prolonged, repetitive tasks.
SIT-STAND ADJUSTABLE WORK SURFACE
Use a sit-stand adjustable desk when ...
Your tasks constrain your movements for a prolonged period of time (for example, tasks requiring a high degree of fine-motor hand-eye coordination in a small, fixed area, like dental work).
- Your job is highly sedentary or is prolonged for long periods
Recommended work surface heights
When purchasing desks for groups of workers of varying heights, we recommend the following minimum and optimal heights:
Height for Sitting Adjustable Work Surfaces
Minimum: 25” - 30”; Range = 5”
Optimal: 22” - 33”; Range = 11”Height for Standing Adjustable Work Surfaces
Minimum: 38” - 42”; Range = 4”
Optimal: 35” - 47”; Range = 12”Height for Sit-to-stand Adjustable Work Surfaces
Minimum: 26” - 40”; Range = 15"
Optimal: 22” - 47”; Range = 25"
100 North Rancho Road, Suite #1
Thousand Oaks, CA 91362
Phone (805)495-3937 Fax (805)373-9843
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