What does this sign mean?

I was trolling the Your Scene section of The Times' website and came across this reader-submitted photo. Unfortunately, the reader who submitted it -- someone with the screen name of Magawa -- didn't include any of the pertinent information, such as where it was taken and what the sign means.

A couple of readers left comments. One said it meant no siestas, another suggested it was telling motorists not to honk. Beats me. But Bottleneckers have long been known for their worldly ways and deductive skills, so I thought one of you could shed some light. Leave a comment and I'll update this post later.

-- Steve Hymon

Photo credit: Magawa

Comments

[Aaron]

No more than 10 band members to a single vehicle :).

[Jose]

Looks like a quiet zone around a hospital entrance, hence the low speed.

[johnny]

All vehicles are limited to 10 bugles or less beyond this point.

[K.Lee]

I think it means not to use the horn, and the speed limit is 10 (km/h or mph, I'm not sure)

[Ben H.]

No music after 10pm? :-)