Allegheny Mountain Tunnel, and between Bensalem and the Delaware River Bridge. On May 2, 2016, PennDOT announced that the speed limit would be increased to on about of roadway across the state, including rural stretches of I-79, I-80, I-99, I-380, and US 15, with conversion to take place on May 3. On non-freeway roads, speed limits are generally held at for rural four-lane roads, for rural two-lane roads, for urban four lane roads and 40–45 (sometimes, but rarely, 50 mph) mph (64–72 km/h) for urban two lane roads, 35–45 mph for roads in commercial business areas, 30 for major roads in residential areas, 20 for most municipal residential streets, including main north–south and east–west roads in county seats and other mid-sized to large towns, and 15 for school zones during school arrival and departure times only. It is also only in effect on days that the school the road goes near is in session. Many schools have signs that blink when the school speed limit is in effect. There is no reduced school speed on divided highways, even if the school sits right beside the highway. All state-owned two-lane roads in rural areas within Pennsylvania have a default speed limit of 55 mph unless otherwise posted. The Pennsylvania Turnpike has a minimum speed limit of 15 mph below the posted maximum speed, though the minimum is only sporadically posted. This is not enforced for slow-moving trucks in areas with steep grades and signs are posted that instruct drivers to use their flashers if traveling below 50 mph (40 if the speed limit is 55). Pennsylvania has no default minimum speed limit on any other roads. However, minimum speed limits on certain highways may be enacted and posted as provided by Section 3364(c) of the Pennsylvania Motor Vehicle Code (Title 75 of the Pennsylvania Consolidated Statutes). §3364(a) also requires, "Except when reduced speed is necessary for safe operation or in compliance with law, whenever any person drives a vehicle upon a roadway having width for not more than one lane of traffic in each direction at less than the maximum posted speed and at such a slow speed as to impede the normal and reasonable movement of traffic, the driver shall, at the first opportunity when and where it is reasonable and safe to do so and after giving appropriate signal, drive completely off the roadway and onto the berm or