1. Find the working part
Identify the button, grip or other point used to operate the element. Mark its height from the finished floor. A large enclosure can hide a hard-to-reach working part.
Physical accessibility · Reach & use
Put the control
within comfortable reach.
Explore how an approach and an obstruction change the space needed to reach a switch, handle or other operable part. Compare selected ADA 2010 adult reach dimensions, then record what still needs checking on site.
Choose the real approach.
Measurements stay in this tab. Nothing is uploaded or saved automatically. Blank dimensions remain unverified.
Selected dimensional comparison
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Selected dimensions only. Matching these numbers does not establish accessibility or compliance. Special scoping, local requirements, children’s ranges, kitchens, refrigerators, laundry equipment, fuel dispensers and protruding-object requirements are outside this calculator.
Still check on site
Selected reference: ADA 2010 §308. Also review §309 operable parts and the Access Board guide.
Measure the action, then the approach.
2. Observe the obstruction
Record the reach direction and horizontal distance. A high reach over a surface needs a different check from reaching beside an element. Keep photographs and measurements together in your field notes.
3. Try the whole task
Provide an accessible approach and floor space. For forward reaches over an obstruction, knee and toe space must extend at least as far as the reach. Test whether a person can position, reach, operate and leave.
A reachable control must also be usable. Check one-handed operation, grip and activating force. A height comparison cannot tell whether a person can identify a control, understand feedback or operate it reliably. Include people with different reach and dexterity in testing.
Keep the selected reference visible.
| Reach situation | Depth | Control height | Reference |
|---|---|---|---|
| Unobstructed forward or side | Unobstructed | 15–48 | 308.2.1 / 308.3.1 |
| Side, shallow offset | ≤10 | 15–48 | 308.3.1 exception 1 |
| High forward, over obstruction | ≤20 / >20 to 25 | Maximum 48 / 44 | 308.2.2 |
| High side, over obstruction | ≤10 / >10 to 24 | Maximum 48 / 46 | 308.3.2; obstruction ≤34 high |
High-reach rows do not define a low-reach minimum. Check the control’s actual position, the applicable element rules and floor clearances separately.
Sources: official ADA 2010 reach ranges, operable parts, and Access Board operable-parts guide. Reviewed September 2026. The reference values are US requirements; this tool does not choose the law for your project.