Accelerated decay tests with miniaturised wood specimens – critical assessment of suitability for durability classification

Figures & data

Table 1. Median percentage mass loss (ML_F), durability classes (DC) based on ML_F and on x-values referring to ML_F of mini-block and EN 113-2 standard specimens after different incubation periods.

Wood species	T. versicolor						C. puteana
	EN 113-2		Mini-block				EN 113-2		Mini-block
	8 w	16 w	6 w	8 w	10 w	16 w	8 w	16 w	6 w	8 w	10 w	16 w
Median percentage mass loss MLF (%)
European beech	17.1	30.2	20.5	35.5	41.1	56.6	20.9	26.8	41.9	40.7	21.4	40.9
English oak	6.3	13.7	11.1	18.0	21.1	36.4	1.2	1.7	−0.5	0.7	1.7	2.0
Black locust	1.3	4.0	1.5	2.8	3.5	10.8	0.4	0.6	−0.3	0.2	0.7	0.6
Flooded gum	6.1	15.4	7.8	15.0	20.3	35.1	1.9	5.4	−1.5	−0.3	0.6	0.3
Scots pine sw	9.3	20.4	8.0	10.4	15.4	31.0	18.8	23.3	15.5	18.8	20.0	28.4
Scots pine hw	8.9	13.3	7.4	12.1	16.7	37.4	18.3	24.9	24.8	31.8	19.4	30.3
Norway spruce	10.8	19.5	11.0	13.2	23.5	42.1	17.5	22.1	1.1	2.2	9.1	10.9
European larch	3.7	8.1	4.5	6.2	8.9	17.6	4.0	9.4	1.4	1.9	2.9	2.1
Douglas fir	1.5	3.8	1.0	1.0	3.1	9.1	11.4	20.9	−1.5	−1.2	0.3	−0.1
Lebanon cedar	1.9	6.0	1.9	4.5	7.0	13.9	9.2	31.2	1.7	1.2	3.8	4.3
Durability classes based on the median percentage mass loss (MLF)
English oak	2	3	3	4	4	5	1	1	1	1	1	1
Black locust	1	1	1	1	1	3	1	1	1	1	1	1
Flooded gum	2	4	3	4	4	5	1	2	1	1	1	1
Scots pine hw	2	3	2	3	4	5	4	4	4	5	4	5
Norway spruce	3	4	3	3	4	5	4	4	1	1	2	3
European larch	1	2	1	2	2	4	1	2	1	1	1	1
Douglas fir	1	1	1	1	1	2	3	4	1	1	1	1
Lebanon cedar	1	2	1	1	2	3	2	5	1	1	1	1
Durability classes based on x-values
English oak	3	4	4	4	4	4	1	1	1	1	1	1
Black locust	1	2	1	1	1	2	1	1	1	1	1	1
Flooded gum	3	4	3	3	4	4	1	3	1	1	1	1
Scots pine hw	5	4	5	5	5	5	5	5	5	5	5	5
Norway spruce	5	5	5	5	5	5	5	5	1	2	4	3
European larch	3	3	4	4	4	4	3	3	2	2	3	2
Douglas fir	2	2	2	1	3	3	4	5	1	1	1	1
Lebanon cedar	3	3	3	3	4	3	4	5	2	1	2	2

Notes: Bold = Fungus with the highest ML_F under standard conditions, i.e. 16 weeks of incubation according to EN 113-2. sw = sapwood, hw = heartwood.

Figure 1. Relationship between median mass (ML_F) loss by T. versicolor and C. puteana of mini-block specimens after different incubation times and standard EN 113-2 specimens after 16 weeks of incubation. Each dot represents the median of ten replicate specimens per wood species.