---
title: usage
framework: sensorkit
role: symbol
role_heading: Instance Property
path: sensorkit/srphotoplethysmogramsample/usage-swift.property
---

# usage

The method that the person or system uses to take the reading.

## Declaration

```swift
var usage: [SRPhotoplethysmogramSample.Usage] { get }
```

## See Also

### Accessing PPG data

- [startDate](sensorkit/srphotoplethysmogramsample/startdate.md)
- [nanosecondsSinceStart](sensorkit/srphotoplethysmogramsample/nanosecondssincestart.md)
- [SRPhotoplethysmogramSample.Usage](sensorkit/srphotoplethysmogramsample/usage-swift.struct.md)
- [opticalSamples](sensorkit/srphotoplethysmogramsample/opticalsamples.md)
- [SRPhotoplethysmogramOpticalSample](sensorkit/srphotoplethysmogramopticalsample.md)
- [accelerometerSamples](sensorkit/srphotoplethysmogramsample/accelerometersamples.md)
- [SRPhotoplethysmogramAccelerometerSample](sensorkit/srphotoplethysmogramaccelerometersample.md)
- [temperature](sensorkit/srphotoplethysmogramsample/temperature.md)