The nomenclature and meaning of these signals are the following:
R-300. Minimum separation. Prohibition of driving without maintaining a separation equal to or greater than that indicated in the sign with the preceding vehicle, except to overtake. If the indication in metres doesn’t appear, remember that generally the safety distance between vehicles established in article 54 must be kept.
R-301. Maximum speed. Prohibition of driving at a higher speed, in kilometres per hour, than indicated in the sign. This should be followed from the place where it is located until the next sign “End of speed limit”, of “End of prohibitions” or another of “Maximum speed”, unless it is placed on the same post as a warning sign or in the same panel as this, in which case the prohibition ends when the indicated danger ends. Located on a road without priority, it ceases to be valid when leaving an intersection with a priority road. If the limit indicated by the sign coincides with the maximum speed allowed for the type of road, it generally retains the prohibition to overcome it.
R-302. Right turn prohibited. Prohibition of turning to the right.
R-303. Turn left prohibited. Prohibition to turn left. It also includes the prohibition of changing the direction of travel.
R-304. U-turn prohibited. Prohibition to carry out the manoeuvre of a change of direction.
R-305. Overtaking prohibited. In addition to the general principles on overtaking, it indicates the prohibition of all vehicles to overtake motor vehicles travelling on the road, unless they are two-wheeled motorcycles and provided that they do not go on the zone reserved for vehicles travelling in the opposite direction, from the place where the sign is located and until the next signal of «End of prohibition of overtaking» or «End of prohibitions». Placed in areas where overtaking is prohibited as a rule, it generally retains the prohibition to carry out this manoeuvre.
R-306. Prohibited for trucks to overtake. Prohibition of trucks whose maximum authorized mass exceeds 3,500 kilograms to overtake motor vehicles travelling on the road, unless these are two-wheeled motorcycles and provided that the area reserved in the opposite direction is not invaded, from the place where the signal is located and until the next “End of prohibition of overtaking for trucks” or “End of prohibitions” sign.
R-307. Stopping and parking prohibited. Prohibition of stopping and parking on the side of the road where the sign is located. Unless otherwise indicated, the prohibition begins at the vertical of the sign and ends at the nearest intersection.
R-308. Parking prohibited. Prohibition of parking on the side of the road where the sign is located. Unless otherwise indicated, the prohibition begins vertically along from the sign and ends at the nearest intersection. Stopping is not prohibited.
Remember that if the sign bears an attached notice on the same sign, it is informing when this prohibition is applicable.
In this case, we can see how a temporary parking sign has been placed, it shows the day or days, times and the reason.
R-308 a. Parking prohibited on odd days. Prohibition of parking, on the side of the road where the signal is located, on odd days. Unless otherwise indicated, the prohibition begins vertically along from the sign and ends at the nearest intersection. Stopping is not prohibited.
R-308 b. Parking prohibited on even days. Prohibition of parking, on the side of the road where the signal is located, on even days. Unless otherwise indicated, the prohibition begins vertically along from the sign and ends at the nearest intersection. Stopping is not prohibited.
R-308 c. Parking prohibited the first fortnight of the month. Prohibition of parking, on the side of the road where the sign is located, from 9am on day 1 to 9am on day 16. Unless otherwise indicated, the prohibition begins vertically along from the sign and ends at the nearest intersection. Stopping is not prohibited.
R-308 d. Parking prohibited on second fortnight of the month. Prohibition of parking on the side of the road where the sign is located, from 9am on the 16th until 9am on day 1 of the following month. Unless otherwise indicated, the prohibition begins vertically along from the sign and ends at the intersection closer. Stopping is not prohibited.
R-308 e. Parking prohibited in access. Prohibits parking in front of an access such as a garage or driveway.
R-309. Limited parking area. Parking area of limited duration and obligation for the driver to indicate, in a regulatory manner, the start time of parking. It may include the maximum authorised parking time and the effective time of the limitation. It can also be included if parking is subject to payment.
R-310. Acoustic warnings prohibited. The general prohibition of making acoustic signals, except to avoid a collision.
