Exposure | Particle filtered air | Non-filtered air | ||
---|---|---|---|---|
 | After entry | After 5 h | After entry | After 5 h |
SDNN, ms | 68 (41;115) | 48 (27;82) | 60* (31;116) | 52 (26;99) |
HFn | 28 (16;55) | 31 (10;58) | 30 (11;69) | 29 (13;54)* |
LFn | 68 (27;89) | 66 (30;90) | 66 (27;90) | 70 (37;86)# |
LF/HF ratio | 2.4 (0.6;5) | 2.1 (0.5;10) | 2.3 (0.4;8) | 2.5 (0.8;7) |