Hospital OPD wayfinding: signs nobody sees in time
A 420-bed hospital in Chennai opens a new outpatient block. The main entrance leads into a 24 m × 18 m atrium with a 5.2 m ceiling. Radiology is on level 2; the pharmacy is at the rear of level 1; phlebotomy is at the far end of a 40 m corridor with two side openings. Six signboards have been installed at 2.4 m to the centre, with 200 mm dark-green letters on a grey background, in English only. A survey of first-time visitors finds that 62% asked staff for directions at least once. At peak, 09:00–11:00, about 300 patients an hour pass through and the help desk fields roughly 90 directional queries. Of the patients, 41% read Tamil only and 28% read Tamil and English. The recurring complaint is: "I didn't see the sign until I had walked past it."
1. Using the numbers, explain why the signs fail and name the single biggest error.
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The biggest error is placement at decision points, not letter size. A 200 mm letter read at 2.4 m is legible from roughly 40 m, so legibility is not the failure.
The atrium is 5.2 m high and 24 m across. A sign centred at 2.4 m sits above the natural scanning band of someone walking and looking 3–8 m ahead, so it enters the field of view only when the visitor is already underneath it - precisely the complaint recorded.
Six boards for at least five destinations plus two corridor junctions is also too few. Ninety queries an hour against 300 patients means nearly one in three people needs help, which is a systematic failure rather than a few confused individuals. English-only excludes 41% of patients outright, and dark green on grey gives a low luminance difference, so the board recedes in a bright atrium.
Order of severity: placement, then language, then contrast, then quantity.
2. Redraw the signage strategy: how many decision points, at what height, in what language hierarchy, with what information at each?
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Seven decision points, no more: the entrance threshold (all destinations, arrows, walking time), the foot of the escalator, the level 2 lift lobby, the two corridor openings, the pharmacy approach, and the phlebotomy door itself.
Sign centres at 1.9–2.1 m, set perpendicular to the direction of approach so they are read face-on, and repeated on the floor as a 150 mm coloured line for phlebotomy because a 40 m corridor needs a continuous cue, not a single board.
Language order: Tamil first at about 1.5× the English size, English second, same typeface. The 28% who read both should not have to choose, and the 41% who read Tamil only should never meet English first. Colour plus icon per destination, used identically on every board, so the pharmacy is always the same green and the same symbol.
One 'you are here' plan at the entrance only. Plans placed deeper in the building fail because people cannot mentally rotate them.
3. Design a six-week, low-cost measurement that would tell you whether the change worked.
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Two measures, same hours, same staff, same weekday, before and after.
First, directional queries at the help desk per 100 patients. Baseline is roughly 30 per 100; target under 12.
Second, and this is the one that actually proves it, a wayfinding walk-through: 30 first-time visitors are given a destination card and asked to reach it while an observer follows without helping. Record wrong turns and time to arrival. Match the before and after groups on language mix and age spread, or the comparison is meaningless.
The help-desk count alone can fall for the wrong reasons - staff reassigned, patients giving up, a new queue system. The walk-through catches the case where people stop asking and start wandering, which looks like improvement in the counts and is the opposite in reality.