加拿大Albert 省的设计标准：

http://www.th.gov.bc.ca/publications/eng_publications/electrical/most_pm.pdf
If a STOP sign cannot be seen from a distance in advance of the
stop line equivalent to Condition B of Table 1, Appendix A-1, a W-
11 STOP AHEAD sign should be erected so that it can be seen
from that distance. W-11 signs may also be warranted where the
stop is unexpected, where speeds are high or for an educational
period at newly installed STOP signs

 

 

W-128 DIVIDED HIGHWAY AHEAD SIGN
The W-128 DIVIDED HIGHWAY AHEAD tab sign indicates to
motorists that they are approaching an intersection with a divided
highway. This sign should be used in advance of four-lane divided
highways with “at grade” intersections, where the minor road is
controlled by an R-1 STOP sign.
The W-128T tab may temporarily be used with the W-128 sign for
an educational period.
Installation guideline: Condition B, Table 1, (Appendix).