Inter-use stagnation times

Table 3.1 Inter-use stagnation times for different household sizes (Bailey et al., 1986h)...

Mean inter-use stagnation time time between draw for dietetic purposes and the previous draw. 

As shown, a variation of 10 minutes in mean inter-use stagnation time, which is quite normal (Bailey found standard deviations up to 22 minutes, depending on household size), has considerable influence on the average weekly intake of lead via drinking water. Furthermore, this figure shows that by lowering the mean... 

Figure 3.2 Influence of variations in inter-use stagnation time on average weekly lead concentration...

These results show clearly the great spread in mean inter-use times that can be observed in different households. As metal concentrations rise rapidly in this range of stagnation times, it can be concluded that metal concentrations might vary widely between households. 

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