# helsinki

`https://hel.fi/models/helsinki/helsinki/views/dh54wtluwvyhzmdsaosg3xpmgdadyoxg`

## NoiseZone

One area of the city's 2022 noise survey: the ground where the day or the night sound level of one traffic source falls into one 5 dB band, as the Smart Data Model extension NoiseZone \(PointOfInterest base\).

| Slot | Range | Kind | Required | Multivalued | Description |
|---|---|---|---|---|---|
| location | string | GeoProperty | no | no | Where the entity is, as GeoJSON geometry. |
| name | string | LanguageProperty | no | no | The name, per language. |
| noiseLevelLow | float | Property | no | no | The lower bound of the area's 5 dB noise band, the A-weighted equivalent sound level \(LAeq\) the city's 2022 noise survey computes 2 m above ground, in decibels. |
| noiseLevelHigh | float | Property | no | no | The upper bound of the area's 5 dB noise band, in decibels; the loudest band has none. |
| assessmentPeriod | NoiseAssessmentPeriod | Property | yes | no | The part of the day the noise level holds for, as the Finnish guideline values count it: the day, 07:00 to 22:00, or the night, 22:00 to 07:00. |
| noiseSource | NoiseSource | Property | yes | no | The traffic whose noise the area's band computes: streets and roads, the main railway, the metro or the tram. A custom property: the NoiseZone extension holds one source per map. |
| dataProvider | string | Property | no | no | Who publishes the data the entity was read from, as an application credits it beside the licence \(CC BY 4.0 for every feed of this space\). |
| source | uri | Property | no | no | The open-data service the entity was read from. |

## NoiseAssessmentPeriod (enum)

The parts of the day a noise band of the 2022 survey holds for.

- day: The day, 07:00 to 22:00 \(LAeq 7-22\).
- night: The night, 22:00 to 07:00 \(LAeq 22-7\).

## NoiseSource (enum)

The traffic sources the 2022 noise survey computes one map each for.

- metro: The metro.
- railway: The main railway \(juna\).
- roadTraffic: Streets and roads \(kadut ja maantiet\).
- tram: The tram \(raitiovaunu\).