5 Traffic Signal and Road Sign Rules That Should Be Standardized Across Japan

Japanese traffic rules are established nationwide through the Road Traffic Act and its associated enforcement orders, enforcement regulations, and road traffic regulations. However, there are actually quite a few "local rules" for traffic signal indication regulations and road sign installations that vary by prefecture. As a result, this can cause confusion for drivers, pedestrians, and tourists when they visit other prefectures. Below are five traffic rules that could improve safety and convenience if standardized nationwide.

Types of vehicles exempted from 'No Entry' and 'No Parking' regulations

The rules for specific vehicle exemptions on supplementary signs attached to nationwide 'One-Way' and 'No Entry' signs are not standardized across the country. Even on residential roads, some prefectures do not exempt bicycles at all, while others exempt motorized bicycles or motorcycles, and some even only prohibit 'motor vehicles with three or more wheels'.

Furthermore, even for the same regulation, the notation can differ. For example, 'Automobiles/Motorized Bicycles' and 'Excluding Light Vehicles' mean the same thing, but most people cannot interpret them that way.

On residential roads in urban areas, I would like to see these standardized nationwide into about three patterns, including the notation, such as '🚘️🏍️ (Automobiles/Motorized Bicycles)', '🚘️ (Automobiles (excluding two-wheeled vehicles))', and others with no exemptions.

This is the same for 'No Parking' regulations; broadly speaking, there are prefectures that exempt two-wheeled vehicles, motorized bicycles, and bicycles.

I would also like to see this standardized nationwide into about two patterns, including the notation, for cases where two-wheeled vehicles/motorized bicycles/bicycles/light vehicles are exempted and cases where they are not.

Patterns of 'No Through Traffic' types and the perception of 'weekdays' in regulations

For 'No Through Traffic', multiple signs containing one or two vehicle symbols are lined up to indicate the types of vehicles, including '(310) No Through Traffic (Combination)', but it can also be expressed by listing vehicles on a supplementary sign under '(302) No Through Traffic', or by using blue regulatory signs for 'XXX Only'. The same regulatory content can be expressed using these three methods.

And these roughly three patterns vary in preference depending on the prefecture, or have different detailed conditions (for example, only 'Large Special Vehicles' are excluded). I would like to see these methods of expressing regulations standardized into a small number of variations to make them easier to understand.

In addition, given that Saturdays have become considered holidays rather than weekdays in social norms between the 1980s and the 2000s, some prefectures have updated regulations related to school zones and vehicle congestion hours to reflect this, while others have not.

As a result, two subtly different patterns remain: 'Excluding Sundays and Holidays' and 'Excluding Saturdays, Sundays, and Holidays'. Regarding school zones, the morning and evening school commute hours also differ by municipality, and I would like to see these regulated time periods standardized as much as possible.

Methods of regulatory notification indicated by multiple irregular arrow signs

The 'No Entry Except Specified Direction' regulatory sign (commonly known as the arrow sign) exists in countries that are signatories to the UN 'Convention on Road Signs and Signals', but Japan has complex signs that customize the number and direction of arrows, such as (311-E). These are called 'irregular arrows' among enthusiasts.

The background to the creation of complex irregular arrows is that when multiple 'No Entry' or 'No Through Traffic' regulations are applied to minor roads at a single intersection, it may be necessary to have that many 'No Entry Except Specified Direction' regulatory signs on the main road to express those regulations. In the case of complex intersections such as five-way or six-way junctions, the probability of having multiple regulations increases.

Incidentally, usually (except for some regulations such as 'No Right Turn'), regulatory signs for 'No Through Traffic' or 'No Entry' are installed on the minor road, but in that case, if a full set of regulatory signs is placed, the 'No Entry Except Specified Direction' regulatory sign on the main road becomes a redundant regulatory sign, and it serves more as a regulatory warning sign.

There are roughly four types of these 'regulatory warning signs': ❶ None (Tokyo, etc.), ❷ 'No Entry Except Specified Direction' sign, ❸ Regulatory warning sign (sign + text), and ❹ Regulatory warning sign (map) (Chiba Prefecture, etc.).

Among these, the easiest to understand is ❹ Regulatory warning sign (map) (Chiba Prefecture, etc.), but it takes time and effort because it is necessary to create a customized sign for each location.

If possible, it would be easier for drivers if these were standardized across all of Japan.

Signs and boards for 'Watch out for darting out' and 'Watch out for rear-end collisions'

There is a high demand for 'Watch out for darting out' signs for pedestrians, especially in urban areas, residential neighborhoods, and near nurseries, kindergartens, schools, and parks where there are many pedestrians. However, 'Watch out for darting out' is not in the Sign Ordinance, and because it is not in the 'List of Signs' issued by the Ministry of Land, Infrastructure, Transport and Tourism, each local government produces them with their own designs.

If forced to choose, '(208) School, Kindergarten, Nursery, etc. ahead' is close, and some local governments adopt this, but since there are various situations, such as installing them where there is no school or calling attention to elderly people or bicycles darting out, original signs are often used.

Also, there is a need for 'Watch out for rear-end collisions,' mainly on arterial roads, and there are various variations depending on the local government. This is also not in the Sign Ordinance, and because it is not in the 'List of Signs' issued by the Ministry of Land, Infrastructure, Transport and Tourism, each local government produces them with their own designs. The Ministry of Land, Infrastructure, Transport and Tourism issued 'Improvement of Future Guidance (Signs)' in 2016 and proposed improvements.

Regional differences in traffic signal display methods

The meaning of traffic signal lights is determined by the Road Traffic Act.

However, it is not widely known that there are cases where multiple methods are mixed regarding their displays. A 'display' refers to the order in which green lights, etc., are shown to regulate traffic from different directions.

For example, there are two types of displays for push-button traffic signals installed at pedestrian crossings on single roads. They are commonly called 'Always-Green Main Road Method' and 'Main Road Flashing Method' (*These are colloquial names as they do not appear in government documents).

The 'Always-Green Main Road Method' is now mainstream, but the 'Main Road Flashing Method' is still used in Aichi, Mie, Shiga, Hiroshima, Ehime, Fukuoka, and other prefectures, and was once used in the Tokyo metropolitan area and other prefectures as well. It seems there is a trend toward standardizing to the 'Always-Green Main Road Method' in the future.

A flashing yellow light means 'proceed with caution,' but since a certain number of vehicles slow down thinking they must go slowly, which can cause traffic jams, I hope it will be standardized soon.

*

As for other signal patterns, the display of arrow signals can also differ by prefecture.

For example, whether or not a yellow light is inserted when switching from a right-turn arrow signal to a red light differed by prefecture. Recently, cases where it is changed to include a yellow light are increasing. And, although it is very subtle, there is also a display where it becomes only a red light for an instant when entering the 3-phase signal, and then the right arrow lights up with a delay.

Also, special displays for time-difference signals are still in operation depending on the local government. The National Police Agency indicated the operational policy for time-difference signals in the guidelines revised in 2008 (Heisei 20), 'Regarding the Establishment of Operational Guidelines for Control by Time-Difference Signal Displays (Notification),' and is moving toward standardizing displays nationwide.