| Studies on the relation between Net Working Time and Recess Periods from Pulse Frequence in Thinning operations of Japense Larch(Kang, 2000) | Heart rate | 1 | Overall Value |
| A study on Work Load of Tree Felling Work Using Maximal Oxygen Uptake and Heart Rate(Park, 1996) | Heart rate | 4 | Average |
| Analysis of Working Posture Using OWAS in Forest Work(Lee and Park, 2001) | Heart rate and Action category | 2 | Overall Value |
| Heart rate strain of forest-workers in weeding(Mun et al., 2014) | Heart rate | 4 | Median |
| Postural Risk Assessment of Weed and Kudzu Removal Operations(Lee et al., 2020) | Action category | 6 | Median |