G03.04 - Biological Deterioration

SIGNIFICANCE AND USE
4.1 The resin portion of plastic materials is usually resistant to bacteria, in that it does not serve as a carbon source for the growth of bacteria. It is generally the other components, such as plasticizers, lubricants, stabilizers, and colorants that are responsible for bacterial attack on plastic materials. It is important to establish the resistance of plastics to microbial attack when plastics are used under conditions of high temperature and humidity favorable for such attack.  
4.2 The effects to be expected are:  
4.2.1 Surface attack, discoloration, and loss of transmission (optical).  
4.2.2 Removal of susceptible plasticizers, modifiers, and lubricants, resulting in increased modulus (stiffness), changes in weight, dimensions, and other physical properties, and deterioration of electrical properties such as insulation resistance, dielectric constant, power factor, and dielectric strength.  
4.3 Often the changes in electrical properties are due principally to surface growth and associated moisture, and to pH changes caused by products of bacterial metabolism. Other effects include preferential growths caused by nonuniform dispersion of plasticizers, lubricants, and other processing additives. Pronounced physical changes may be observed on products in film form or as coatings where the ratio of surface to volume is high, and where nutrient materials such as plasticizers and lubricants continue to diffuse to the surface as they are utilized by the organisms.  
4.4 Since attack by organisms involves a large element of change due to local accelerations and inhibitions, the order of reproducibility may be rather low. To assure that estimates of behavior are not too optimistic, the greatest observed degree of deterioration should be reported.  
4.5 Conditioning of specimens such as exposure to leaching, weathering, heat treatment, etc., may have significant effects on the resistance of plastics to bacteria. Determination of these effects is not covered i...
SCOPE
1.1 This practice covers two procedures, A and B, for determining the effect of bacteria on the properties of plastics in the form of molded and fabricated articles, tubes, rods, sheets, and film materials. Procedure B provides a more extensive contact between the test bacteria and the specimens than does Procedure A. Changes in optical, mechanical, and electrical properties may be determined by the applicable ASTM methods.  
1.2 The values stated in SI units are to be regarded as the standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
3.1 Bodies of water, such as swimming pools, artificial ponds, and irrigation ditches often are lined with polymeric films. Cyanobacteria tend to grow in such bodies of water under the proper atmospheric conditions, and they can produce slimy and unsightly deposits on the film. The method described herein is useful in evaluating the degree and permanency of protection against surface growth of cyanobacteria afforded by various additives incorporated in the film.
SCOPE
1.1 This practice covers the determination of the susceptibility of polymeric films to the attachment and proliferation of surface-growing cyanobacteria.  
1.2 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
4.1 The synthetic polymer portion of these materials is usually fungus-resistant in that it does not serve as a carbon source for the growth of fungi. It is generally the other components, such as plasticizers, cellulosics, lubricants, stabilizers, and colorants, that are responsible for fungus attack on plastic materials. To assess materials other than plastics, use of this test method should be agreed upon by all parties involved. It is important to establish the resistance to microbial attack under conditions favorable for such attack, namely, a temperature of 2 to 38 °C (35 to 100 °F) and a relative humidity of 60 to 100 %.  
4.2 The effects to be expected are as follows:  
4.2.1 Surface attack, discoloration, loss of transmission (optical), and  
4.2.2 Removal of susceptible plasticizers, modifiers, and lubricants, resulting in increased modulus (stiffness), changes in weight, dimensions, and other physical properties, and deterioration of electrical properties such as insulation resistance, dielectric constant, power factor, and dielectric strength.  
4.3 Often the changes in electrical properties are due principally to surface growth and its associated moisture and to pH changes caused by excreted metabolic products. Other effects include preferential growth caused by nonuniform dispersion of plasticizers, lubricants, and other processing additives. Attack on these materials often leaves ionized conducting paths. Pronounced physical changes are observed on products in film form or as coatings, where the ratio of surface to volume is high, and where nutrient materials such as plasticizers and lubricants continue to diffuse to the surface as they are utilized by the organisms.  
4.4 Since attack by organisms involves a large element of chance due to local accelerations and inhibitions, the order of reproducibility may be rather low. To ensure that estimates of behavior are not too optimistic, the greatest observed degree of deterioration should be reported...
SCOPE
1.1 This practice covers determination of the effect of fungi on the properties of synthetic polymeric materials in the form of molded and fabricated articles, tubes, rods, sheets, and film materials. Changes in optical, mechanical, and electrical properties may be determined by the applicable ASTM methods.  
1.2 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
3.1 These results may be used to compare the susceptibility of materials when exposed to this test procedure.  
3.2 Microbiological susceptibility may be reflected by a number of changes including staining, weight loss, or reduction in tensile or flexural strength.  
3.3 This practice may be considered an inoculation with a mixed culture of fungi and bacteria.
SCOPE
1.1 This practice is limited to the method of conducting an evaluation of a nonmetallic material's microbiological susceptibility when in contact with the natural environment of the soil under use conditions. This practice is intended for use on solid material test specimens that are no larger than approximately 2 cm (0.79 in.) thick and 100 cm 2  (15.5 in.2) or on film forming materials such as coatings which may be tested in the form of films at least 50 by 50 mm (2 by 2 in.) in size. This practice may be applied to articles that do not spend the majority of their service life in soil.  
1.2 A wide variety of properties may be affected by microbial attack depending on material or item characteristics. Standard methods (where available) should be used for each different property to be evaluated. This practice does not attempt to enumerate all of the possible properties of interest nor specify the most appropriate test for those properties. Test methods must, however, be appropriate to the material being tested.  
1.3 Materials intended for use in soil burial applications are often subjected to periods of exposure to solar radiation and other elements of weather for some time before they are buried. Because these exposures may alter the ability of a material to resist the effects of soil-borne microorganisms, it is recommended that this practice be combined with appropriate environmental exposures (for example, solar simulating weathering devices, the hydrolytic effects of extended aqueous contact, or extraneous nutrients) or fabrication into articles (for example, adhesive bonding of seams) which may promote microbiological susceptibility during the service life of the material.  
1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are provided for information purposes only.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
3.1 Bodies of water, such as swimming pools, artificial ponds, and irrigation ditches often are lined with polymeric films. Algae tend to grow in such bodies of water under the proper atmospheric conditions, and they can produce slimy and unsightly deposits on the film. The method described herein is useful in evaluating the degree and permanency of protection against surface growth of algae afforded by various additives incorporated in the film.
SCOPE
1.1 This practice covers the determination of the susceptibility of polymeric films to the attachment and proliferation of surface-growing algae.  
1.2 The values in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 The synthetic polymer portion of these materials is usually fungus-resistant in that it does not serve as a carbon source for the growth of fungi. It is generally the other components, such as plasticizers, cellulosics, lubricants, stabilizers, and colorants, that are responsible for fungus attack on plastic materials. To assess materials other than plastics, use of this test method should be agreed upon by all parties involved. It is important to establish the resistance to microbial attack under conditions favorable for such attack, namely, a temperature of 2 to 38°C (35 to 100°F) and a relative humidity of 60 to 100 %.  
4.2 The effects to be expected are as follows:  
4.2.1 Surface attack, discoloration, loss of transmission (optical), and  
4.2.2 Removal of susceptible plasticizers, modifiers, and lubricants, resulting in increased modulus (stiffness), changes in weight, dimensions, and other physical properties, and deterioration of electrical properties such as insulation resistance, dielectric constant, power factor, and dielectric strength.  
4.3 Often the changes in electrical properties are due principally to surface growth and its associated moisture and to pH changes caused by excreted metabolic products. Other effects include preferential growth caused by nonuniform dispersion of plasticizers, lubricants, and other processing additives. Attack on these materials often leaves ionized conducting paths. Pronounced physical changes are observed on products in film form or as coatings, where the ratio of surface to volume is high, and where nutrient materials such as plasticizers and lubricants continue to diffuse to the surface as they are utilized by the organisms.  
4.4 Since attack by organisms involves a large element of chance due to local accelerations and inhibitions, the order of reproducibility may be rather low. To ensure that estimates of behavior are not too optimistic, the greatest observed degree of deterioration should be reported. ...
SCOPE
1.1 This practice covers determination of the effect of fungi on the properties of synthetic polymeric materials in the form of molded and fabricated articles, tubes, rods, sheets, and film materials. Changes in optical, mechanical, and electrical properties may be determined by the applicable ASTM methods.  
1.2 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 The synthetic polymer portion of these materials is usually fungus-resistant in that it does not serve as a carbon source for the growth of fungi. It is generally the other components, such as plasticizers, cellulosics, lubricants, stabilizers, and colorants, that are responsible for fungus attack on plastic materials. To assess materials other than plastics, use of this test method should be agreed upon by all parties involved. It is important to establish the resistance to microbial attack under conditions favorable for such attack, namely, a temperature of 2 to 38°C (35 to 100°F) and a relative humidity of 60 to 100 %.  
4.2 The effects to be expected are as follows:  
4.2.1 Surface attack, discoloration, loss of transmission (optical), and  
4.2.2 Removal of susceptible plasticizers, modifiers, and lubricants, resulting in increased modulus (stiffness), changes in weight, dimensions, and other physical properties, and deterioration of electrical properties such as insulation resistance, dielectric constant, power factor, and dielectric strength.  
4.3 Often the changes in electrical properties are due principally to surface growth and its associated moisture and to pH changes caused by excreted metabolic products. Other effects include preferential growth caused by nonuniform dispersion of plasticizers, lubricants, and other processing additives. Attack on these materials often leaves ionized conducting paths. Pronounced physical changes are observed on products in film form or as coatings, where the ratio of surface to volume is high, and where nutrient materials such as plasticizers and lubricants continue to diffuse to the surface as they are utilized by the organisms.  
4.4 Since attack by organisms involves a large element of chance due to local accelerations and inhibitions, the order of reproducibility may be rather low. To ensure that estimates of behavior are not too optimistic, the greatest observed degree of deterioration should be reported. ...
SCOPE
1.1 This practice covers determination of the effect of fungi on the properties of synthetic polymeric materials in the form of molded and fabricated articles, tubes, rods, sheets, and film materials. Changes in optical, mechanical, and electrical properties may be determined by the applicable ASTM methods.  
1.2 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
3.1 These results may be used to compare the susceptibility of materials when exposed to this test procedure.  
3.2 Microbiological susceptibility may be reflected by a number of changes including staining, weight loss, or reduction in tensile or flexural strength.  
3.3 This practice may be considered an inoculation with a mixed culture of fungi and bacteria.
SCOPE
1.1 This practice is limited to the method of conducting an evaluation of a nonmetallic material's microbiological susceptibility when in contact with the natural environment of the soil under use conditions. This practice is intended for use on solid material test specimens that are no larger than approximately 2 cm (0.79 in.) thick and 100 cm 2  (15.5 in.2) or on film forming materials such as coatings which may be tested in the form of films at least 50 by 50 mm (2 by 2 in.) in size. This practice may be applied to articles that do not spend the majority of their service life in soil.  
1.2 A wide variety of properties may be affected by microbial attack depending on material or item characteristics. Standard methods (where available) should be used for each different property to be evaluated. This practice does not attempt to enumerate all of the possible properties of interest nor specify the most appropriate test for those properties. Test methods must, however, be appropriate to the material being tested.  
1.3 Materials intended for use in soil burial applications are often subjected to periods of exposure to solar radiation and other elements of weather for some time before they are buried. Because these exposures may alter the ability of a material to resist the effects of soil-borne microorganisms, it is recommended that this practice be combined with appropriate environmental exposures (for example, solar simulating weathering devices, the hydrolytic effects of extended aqueous contact, or extraneous nutrients) or fabrication into articles (for example, adhesive bonding of seams) which may promote microbiological susceptibility during the service life of the material.  
1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are provided for information purposes only.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
Bodies of water, such as swimming pools, artificial ponds, and irrigation ditches often are lined with plastic films. Algae tend to grow in such bodies of water under the proper atmospheric conditions, and they can produce slimy and unsightly deposits on the film. The method described herein is useful in evaluating the degree and permanency of protection against surface growth of algae afforded by various additives incorporated in the film.
SCOPE
1.1 This practice covers the determination of the susceptibility of plastic films to the attachment and proliferation of surface-growing algae.  
1.2 The values in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
The synthetic polymer portion of these materials is usually fungus-resistant in that it does not serve as a carbon source for the growth of fungi. It is generally the other components, such as plasticizers, cellulosics, lubricants, stabilizers, and colorants, that are responsible for fungus attack on plastic materials. To asses materials other than plastics, use of this test method should be agreed upon by all parties involved. It is important to establish the resistance to microbial attack under conditions favorable for such attack, namely, a temperature of 2 to 38°C (35 to 100°F) and a relative humidity of 60 to 100 %.
The effects to be expected are as follows:
Surface attack, discoloration, loss of transmission (optical), and
Removal of susceptible plasticizers, modifiers, and lubricants, resulting in increased modulus (stiffness), changes in weight, dimensions, and other physical properties, and deterioration of electrical properties such as insulation resistance, dielectric constant, power factor, and dielectric strength.
Often the changes in electrical properties are due principally to surface growth and its associated moisture and to pH changes caused by excreted metabolic products. Other effects include preferential growths caused by nonuniform dispersion of plasticizers, lubricants, and other processing additives. Attack on these materials often leaves ionized conducting paths. Pronounced physical changes are observed on products in film form or as coatings, where the ratio of surface to volume is high, and where nutrient materials such as plasticizers and lubricants continue to diffuse to the surface as they are utilized by the organisms.
Since attack by organisms involves a large element of chance due to local accelerations and inhibitions, the order of reproducibility may be rather low. To ensure that estimates of behavior are not too optimistic, the greatest observed degree of deterioration should be reported.
Conditioning of the specimens, ...
SCOPE
1.1 This practice covers determination of the effect of fungi on the properties of synthetic polymeric materials in the form of molded and fabricated articles, tubes, rods, sheets, and film materials. Changes in optical, mechanical, and electrical properties may be determined by the applicable ASTM methods.
1.2 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
These results may be used to compare the susceptibility of materials when exposed to this test procedure.
Microbiological susceptibility may be reflected by a number of changes including staining, weight loss, or reduction in tensile or flexural strength.
This practice may be considered an inoculation with a mixed culture of fungi and bacteria.
SCOPE
1.1 This practice is limited to the method of conducting an evaluation of a nonmetallic material's microbiological susceptibility when in contact with the natural environment of the soil. This practice is intended for use on solid material test specimens that are no larger than approximately 2 cm (¾ in.) thick and 100 cm2  (20 in.2) or on film forming materials such as coatings which may be tested in the form of films at least 50 by 50 mm (2 by 2 in.) in size. This practice may be applied to articles that do not spend the majority of their service life in soil.
1.2 A wide variety of properties may be affected by microbial attack depending on material or item characteristics. Standard methods (where available) should be used for each different property to be evaluated. This practice does not attempt to enumerate all of the possible properties of interest nor specify the most appropriate test for those properties. Test methods must, however, be appropriate to the material being tested.
1.3 It is recommended that this practice be combined with appropriate environmental exposures (for example, sunlight simulating weathering devices, the hydrolytic effects of extended aqueous contact, or extraneous nutrients) or fabrication into articles (for example, adhesive bonding of seams) which may promote microbiological susceptibility during the service life of the material.
1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are provided for information purposes only.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
These results may be used to compare the susceptibility of materials when exposed to this test procedure.
Microbiological susceptibility may be reflected by a number of changes including staining, weight loss, or reduction in tensile or flexural strength.
This practice may be considered an inoculation with a mixed culture of fungi and bacteria.
SCOPE
1.1 This practice is limited to the method of conducting an evaluation of a nonmetallic material's microbiological susceptibility when in contact with the natural environment of the soil and is intended for use on material test specimens that are approximately 2 cm (3/4 in.) thick and 100 cm2 (20 in2) or less. This practice may be applied to articles that do not spend the majority of their service life in soil.
1.2 A wide variety of properties may be affected by microbial attack depending on material or item characteristics. Standard methods (where available) should be used for each different property to be evaluated. This practice does not attempt to enumerate all of the possible properties of interest nor specify the most appropriate test for those properties. Test methods must, however, be appropriate to the material being tested.
1.3 It is recommended that this practice be combined with appropriate environmental exposures (for example, sunlight simulating weathering devices, the hydrolytic effects of extended aqueous contact, or extraneous nutrients) or fabrication into articles (for example, adhesive bonding of seams) which may promote microbiological susceptibility during the service life of material.
1.4 The values stated in parentheses are provided for information only.

SCOPE
1.1 This practice is limited to the method of conducting an evaluation of a nonmetallic material's microbiological susceptibility when in contact with the natural environment of the soil and is intended for use on material test specimens that are approximately 2 cm (3/4 in.) thick and 100 cm2 (20 in2) or less. This practice may be applied to articles that do not spend the majority of their service life in soil.
1.2 A wide variety of properties may be affected by microbial attack depending on material or item characteristics. Standard methods (where available) should be used for each different property to be evaluated. This practice does not attempt to enumerate all of the possible properties of interest nor specify the most appropriate test for those properties. Test methods must, however, be appropriate to the material being tested.
1.3 It is recommended that this practice be combined with appropriate environmental exposures (for example, sunlight simulating weathering devices, the hydrolytic effects of extended aqueous contact, or extraneous nutrients) or fabrication into articles (for example, adhesive bonding of seams) which may promote microbiological susceptibility during the service life of material.
1.4 The values stated in parentheses are provided for information only.

SCOPE
1.1 This practice covers the determination of the susceptibility of plastic films to the attachment and proliferation of surface-growing algae.  
1.2 The values in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
The synthetic polymer portion of these materials is usually fungus-resistant in that it does not serve as a carbon source for the growth of fungi. It is generally the other components, such as plasticizers, cellulosics, lubricants, stabilizers, and colorants, that are responsible for fungus attack on plastic materials. It is important to establish the resistance to microbial attack under conditions favorable for such attack, namely, a temperature of 2 to 38°C (35 to 100°F) and a relative humidity of 60 to 100 %.
The effects to be expected are as follows:
4.2.1 Surface attack, discoloration, loss of transmission (optical), and
4.2.2 Removal of susceptible plasticizers, modifiers, and lubricants, resulting in increased modulus (stiffness), changes in weight, dimensions, and other physical properties, and deterioration of electrical properties such as insulation resistance, dielectric constant, power factor, and dielectric strength.
Often the changes in electrical properties are due principally to surface growth and its associated moisture and to pH changes caused by excreted metabolic products. Other effects include preferential growths caused by nonuniform dispersion of plasticizers, lubricants, and other processing additives. Attack on these materials often leaves ionized conducting paths. Pronounced physical changes are observed on products in film form or as coatings, where the ratio of surface to volume is high, and where nutrient materials such as plasticizers and lubricants continue to diffuse to the surface as they are utilized by the organisms.
Since attack by organisms involves a large element of chance due to local accelerations and inhibitions, the order of reproducibility may be rather low. To ensure that estimates of behavior are not too optimistic, the greatest observed degree of deterioration should be reported.
Conditioning of the specimens, such as exposure to leaching, weathering, heat treatment, etc., may have significant effects on the...
SCOPE
1.1 This practice covers determination of the effect of fungi on the properties of synthetic polymeric materials in the form of molded and fabricated articles, tubes, rods, sheets, and film materials. Changes in optical, mechanical, and electrical properties may be determined by the applicable ASTM methods.
1.2 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 This practice covers determination of the effect of fungi on the properties of synthetic polymeric materials in the form of molded and fabricated articles, tubes, rods, sheets, and film materials. Changes in optical, mechanical, and electrical properties may be determined by the applicable ASTM methods.
1.2 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 This practice covers two procedures, A and B, for determining the effect of bacteria on the properties of plastics in the form of molded and fabricated articles, tubes, rods, sheets, and film materials. Procedure B provides a more extensive contact between the test bacteria and the specimens than does Procedure A. Changes in optical, mechanical, and electrical properties may be determined by the applicable ASTM methods.  
1.2 The values stated in SI units are to be regarded as the standard.

SIGNIFICANCE AND USE
Bodies of water, such as swimming pools, artificial ponds, and irrigation ditches often are lined with plastic films. Algae tend to grow in such bodies of water under the proper atmospheric conditions, and they can produce slimy and unsightly deposits on the film. The method described herein is useful in evaluating the degree and permanency of protection against surface growth of algae afforded by various additives incorporated in the film.
SCOPE
1.1 This practice covers the determination of the susceptibility of plastic films to the attachment and proliferation of surface-growing algae.  
1.2 The values in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.