Biodeterioration tests

Seal, K.J., and Pantke, M., 1986, An interlaboratoiy investigation into the biodeterioration testing of plastics, wiA special reference to polyurethanes Part 1 P dish test. Mater. Org. 21 151-64. 

Efficiency of bio- and photosensitizers is established by the well-known biodeterioration methods of [68] fungal resistance (ASTM G21-70 or G22-76) environmental test methods and other biodeterioration test techniques (see also Chapter 19). 

Pathirana, R. A. Seal, K. J. (1984). Studies on polyurethane deteriorating fungi. 1. Isolation and characterization of the test fungi employed. International Biodeterioration, 20, 163-8. 

Starnecker, A. Menner, M. (1996a). Assessment of biodegradability of plastics under simulated composting conditions in a laboratory test system. International Biodeterioration and Biodegradation, 37, 85-92. 

Whitney, P. J. (1996). A comparison of two methods for testing defined formulations of PVC for resistance to fungal colonization with two methods for the assessment of their biodegradation. International Biodeterioration and Biodegradation, 37, 205-13. 

While the durability of many species has been evaluated with post or stake tests (Figure 9.1), evidence for durability of other species is largely anecdotal. A comprehensive review by Scheffer and Morrell (1998) has helped to collate the literature related to durability for a wide range of wood species. Further, usage is also limited by variability in durability. For some species there are wide differences in heartwood durability between adjacent trees and even between boards cut from the same tree. Also boards can contain both sapwood and heartwood as it is often not economic or practical to cut timber so as to exclude all sapwood. Thus only broad estimates of durability can be developed (Table 9.1). As a result of these sources of variability the use of naturally durable species is often restricted to aboveground applications where the biodeterioration hazard is lower and the consequences of an early failure are less severe. 

Pantke, M., 1977, Test methods for evaluation of susceptibility of plasticized PVC and its components to microbial attack, in Walters, A.H. ed. Biodeterioration Investigation Techniques, 51 - 76. Applied Science, London,... 

Bloomfeld SF, Arthur M, Gibson H, Morley K, Gilbert P, Brown MRW (1995) Development of reproducible test inocula for disinfectant testing. Int Biodeterior Biodegrad 36 ... 

Electrochemical impedance spectroscopy (EIS) has been tested for monitoring biodeterioration of high strength materials and has very high sensitivity. 

Furthermore, collaborative testing was carried out by participants in the Polymer Dispersion Group of the International Biodeterioration Research Group (IBRG) in which the viability in polymer dispersions of 175 microbial species was evaluated (Gillatt, 1995) (Table 9). Sixteen representative organisms were selected from... 

A number of methods are available for evaluating the microbial resistance of polymer dispersions and biocides added to them but there are, as yet, no recognised international standards. Nevertheless, the work of the International Biodeterioration Research Group (IBRG) in this field has lead to the production of a draft method (IBRG, 2001), which, it is believed, can be used as an efficacy test for biocides within the scope of the European Biocidal Products Directive and for predicting the in-use performance of polymer dispersion biocides. 

Unfortunately, routine analysis is not effective in the development of control strategies. Simulation testing of microbial growth on materials frequently includes only selected species of fungi (ASTM 1993a, b, c, d, e). In addition, biodeterioration assessment is rarely quantitative. Modem methods are available to determine biodeterioration kinetics (Gross et al. 1993, 1995,... 

Several other tests have been used also to demonstrate or to evaluate biodegradation. Some of these tests were originally developed to verify resistance against biodeterioration or biofouling. Examples are ASTM G21-90 (resistance to fungi) [72], ASTM G22-76 (resistance to bacteria) [73], NF ENISO11721-1 [74] and NF ENISO 846 [75]. These tests... 

Work is currently in progress to test the potential biodeterioration of 20 different consolidants. 

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