Figure 1
![Position of Plitvice Lakes National Park (red bubble in a small figure), outdoor PM1, PM2.5 and PM10 measurement site indicated with the letter O (φ=44.8811°N, λ=15.6197°E, 579 m ASL) near the trackless train station (V) and indoor measuring site (I). D1 denotes the Karlovac-Split state road [Sources: Google Maps (upper left panel) and Bing Maps (big panel)]](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/64708e6f71e4585e08a9fee6/j_aiht-2022-73-3610_fig_001.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=AKIA6AP2G7AKOUXAVR44%2F20251205%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20251205T052314Z&X-Amz-Expires=3600&X-Amz-Signature=fc78f41d63f2898fea356eb26b0331882971ce9b00d6e3c811df3cc04036cc15&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
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Daily summer and autumn indoor and outdoor PM mass concentrations measured at our outdoor and indoor site and at the Network site
| Indoor PM1 (µg/m3) | Outdoor PM1 (µg/m3) | Outdoor PM2.5 (µg/m3) | Network PM2.5 (µg/m3) | Outdoor PM10 (µg/m3) | Network PM10 (µg/m3) | Visitors (N) | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Sampling height (AGL) | 2 m | 1.7 m | 1.7 m | 4 m | 1.7 m | 4 m | |||||
| Sampling time | 6 min | 1 h avg. | 3 min | 1 h avg. | 3 min | 1 h avg. | 1 h | 3 min | 1 h avg. | 1 h | 24 h |
| Mean+SD | 9.9±3.7 | 9.9±3.6 | 19.3±8.6 | 19.4±8.5 | 22.9±10.3 | 23.0±10.1 | 8.6±6.2 | 28.6±12.4 | 28.8±12.2 | 14.5±9.4 | 9063±3691 |
| Min | 4.4 | 4.4 | 4.0 | 6.5 | 4.5 | 7.5 | 0.0 | 6.6 | 10.1 | 0.1 | 1870 |
| Max | 52.2 | 26.3 | 137.1 | 57.9 | 172.2 | 69.1 | 40.0 | 219.1 | 83.9 | 60.6 | 18722 |