1. Market Research of RWS (with Low mode, without off switch) in Japan
JASIC Noise subcommittee
Koichi Hirata

2. Current situation in Japan
The complaints of RWS from peripheral people and customer are not small.
NBA: Nihon Bus Association
JRCA: Japan Road Contractors Association
JTA: Japan Trucking Association(JTA)

3. Research result of RWS with Low mode, without Off switch in Japan
Tried a new RWS system with Low and Normal mode without Off switch in market
Sound level : Normal mode : 67~76dBA
Low mode (right switch on) : 50~58dBA
RWS off : Unavailable
(For Reference)
Current system conventionally available in market
Sound level : 1 mode only (68~80dBA)
RWS off : available (right switch on)

4. Conclusion
The off mode is necessary in order to solve the complaints to transportation company from peripheral people.
＊For the safety, the Off mode is only approved when following conditions are met.
The other safety device (ex. rear-view camera) is equipped
The automatically returning function to the Normal mode is available.
It is necessary for the driver to be able to select the RWS modes depending on the situation (with automatically returning function to Normal mode).

5. Summary of research result
For the peripheral people’s complaints, RWS needs not only the Low mode but the Off mode. The Low mode is not sufficient to solve the noise environment issue of RWS.
Some customers have serious issues about noise complaints from the neighboring residents. They really need the Off switch of RWS.
Some shipping place have their rule for the transportation company that the RWS have to be turned off in the their yard.
Some transportation companies have an open tender requisite for selecting the vehicle that the RWS Off mode is available.

6. Preconditions for using Off mode
Since RWS is turned off, drivers cannot inform pedestrians, such as visually impaired pedestrians, that the vehicle is approaching. For this reason, in order to ensure the safety, the other safety device (ex. rear- view camera) which enables the driver to detect pedestrians should be equipped.
The automatically returning function to the Normal mode is needed to avoid that the Off mode is used unintentionally.

7. Summary of research result
For the safety, the need of the availability to select the sound level depends on the each area’s condition. (Residential area at night, Road construction area in the tunnel , etc.)
The Low level of RWS are required for the residential area in the night time. RWS has to care the noise environment for the silent area.
The Normal or Higher levels are required for the noisy area and more dangerous area, such as; amusement area, road construction area especially in the tunnel, parking area of highway, the non-sensitive about noise environment area, etc.

8. Customers’ voice (N2 and N3 users)
Area
Comments (Bold ; too large, Blue Italic ; too small)
Miyagi
RWS is necessary, but sound level is too loud even in Low mode when vehicles are parked in the residential area at night time. In this case the Off switch is necessary. (Even though there are no houses when setting up the parking space, many houses are constructed afterwards around the area then there are complaints from peripheral people.)
We need the RWS with Normal mode at the road construction area especially in the tunnel.
Tokyo
RWS is necessary during daytime but it is desirable to turn it off at night time.
Kyoto
The main case of night time delivery. The shipping place requires that the RWS has to be turned off. To solve the noise complaints, reducing the noise level of RWS is not enough, the turning off is necessary. RWS is needed for secure the safety, but we want to turn it off at night.
Some customer’s open tender requisite for selecting the vehicle is equipment of Off switch for RWS.

9. Customers’ voice (N2 and N3 users)
Area
Comments (Bold ; too large, Italic ; too small)
Gunma
Some customers modify the vehicles to attach the retrofit stop switch by themselves, because their delivery time is mainly during the night and they get the complaints about RWS from peripheral people several times.
Low mode is not necessary in order to secure the safety.
Hiroshima
RWS of Low mode is not enough in the busy street at the night time. Some users modify the vehicle so that they can keep the Normal mode.
Users’ demand widely varies depending on their working condition.
So just one selection of mode is not enough to meet the market requirements, both on safety and quiet society.

10. Conclusion
The Off mode is necessary in order to solve the complaints to transportation company from peripheral people.
＊For the safety, the Off mode is only approved when following conditions are met.
The other safety device (ex. rear-view camera) is equipped
The automatically returning function to the normal mode is available.
It is necessary for the driver to be able to select the RWS modes depending on the situation (with automatically returning function to Normal mode).