Fig. 6
From: Damage function for historic paper. Part II: Wear and tear
Accumulation of tears (all sizes) calculated per 100 sheets during the 5–9 challenges (50–90 treatments/instances of handling). Left bound volumes, right unbound folders. The left y-axis shows values for the DP interval: triangle − DP < 300 (N = 5), the right y-axis for all other DP intervals: circle − 300 < DP < 600 (N = 5), open square − 600 < DP < 900 (N = 7). For DP > 900, no mechanical deterioration was caused. The error bars represent the standard deviation for the average number of tears observed in the individual DP interval