"Keep min 2 dots apart" signs?

[Duke87]

In those areas, a succession of signs can be observed
1. In case of fog, pay attention to dots
2. Two dots perceptible = recommended speed of 60 km/h
3. One dot perceptible = recommended speed of 40 km/h

Dots are 33 metres one from another.

Same principle, different application

That strikes me as a much more practical use of these things, since they actually provide the driver with information that's less obvious and routine.

The problem with PennDOT's use of them is that it's just nanny signage, of the sort PennDOT loves to employ - "Buckle up next million miles", etc. These signs are unnecessary clutter because they are instructing drivers to do something that they should be doing all the time without a sign telling them. The point of signs is to provide drivers with situation specific information, like the name of the street at this intersection, or the fact that there is a sharp curve ahead.

[MisterSG1]

This was the actual sign on the 401 in the Whitby section......which looks nearly identical to the one across the pond:



I'm not sure when the sign disappeared as I grew up on the other end of the GTA, but I do last recall seeing it around November 2000ish, so it's quite some time ago....the actual chevrons remained in place until rather recently as can be seen from AsphaltPlanet's photos.

[tckma]

Then again, PA has tons of exclusive signage (like the "truck grade map" signs).

Not exclusive. NYSDOT regions 2 and 4 use them in several locations.

As far as "Bott's Dots", they technically refer only to nonreflective raised pavement markers that are roundish. Stimsonite reflective markers (whether recessed or on the surface) and cat's eyes are not the same thing.

Interestingly enough, when I took driver's ed (in 1995 in New York State), we were taught to keep 1 second of following distance per 10 MPH, and to do this by counting 1 Mississippi, 2 Mississippi, from the time the car ahead of you passed some fixed object on the side of the road like a sign or a tree.  If you passed that sign or tree before you finished counting you were following too closely.  So... 2 dots being 2 seconds at the posted speed limit only meshes with official NYS Driver's Ed Training when the speed limit is 20 MPH.

Of course, no one seriously keeps that much following distance.

[jeffandnicole]

Then again, PA has tons of exclusive signage (like the "truck grade map" signs).

Not exclusive. NYSDOT regions 2 and 4 use them in several locations.

As far as "Bott's Dots", they technically refer only to nonreflective raised pavement markers that are roundish. Stimsonite reflective markers (whether recessed or on the surface) and cat's eyes are not the same thing.

Interestingly enough, when I took driver's ed (in 1995 in New York State), we were taught to keep 1 second of following distance per 10 MPH, and to do this by counting 1 Mississippi, 2 Mississippi, from the time the car ahead of you passed some fixed object on the side of the road like a sign or a tree.  If you passed that sign or tree before you finished counting you were following too closely.  So... 2 dots being 2 seconds at the posted speed limit only meshes with official NYS Driver's Ed Training when the speed limit is 20 MPH.

No it doesn't.  Regardless of the speed, 1 Mississippi 2 Mississippi works out to about a car length for every 10 mph.  Even if you're travelling 70 mph, 2 Mississippis gives you about 7 car lengths of space.