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I-1 APPENDIX I Proposed Draft Standard Specification for Corrugated Polyethylene Drainage Pipe Containing Recycled Polyethylene, 300- to 1,500-mm Diameter

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I-2 Draft Standard Specification for Cor r ugated Polyethylene Drainage Pipe Containing Recycled Polyethylene, 300- to 1500-mm Diameter AASHTO Designation: AASHTO M294-Recycled - XX 1. SCOPE 1.1. This specification covers the requirements and methods of tests for corrugated polyethylene (PE) pipe, couplings, and fittings for use in surface and subsurface drainage applications. 1.1.1. This standard allows for the use of recycled polyethylene in the pipe, but not in the couplings nor the fittings. 1.1.2. Nominal sizes of 300 to 1500 mm are included. 1.1.3. Materials, workmanship, dimensions, pipe stiffness, slow-crack-growth resistance, joining systems, brittleness, and form of markings are specified. 1.2. Corrugated polyethylene pipe is intended for surface and subsurface drainage applications where soil provides support to its flexible walls. Its major use is to collect or convey drainage water by open gravity flow, as culverts, storm drains, etc. Note 1--When polyethylene pipe is to be used in locations where the ends may be exposed, consideration should be given to protection of the exposed portions due to combustibility of the polyethylene and the deteriorating effects of prolonged exposure to ultraviolet radiation. 1.3. This specification does not include requirements for bedding, backfill, or earth-cover load. Successful performance of this product depends upon proper type of bedding and backfill, and care in installation. The structural design of corrugated polyethylene pipe and the proper installation procedures are given in AASHTO's LRFD Bridge Design Specifications, Section 12, and LFRD Bridge Construction Specifications, Section 30, respectively. Upon request of the user or engineer, the manufacturer shall provide profile wall section detail required for a full engineering evaluation. 1.4. The following precautionary caveat pertains only to the test method portion, Section 9 of this specification. 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. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: R 16, Regulatory Information for Chemicals Used in AASHTO Tests AASHTO LRFD Bridge Construction Specifications

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I-3 AASHTO LRFD Bridge Design Specifications Standard Specifications for Highway Bridges 2.2. ASTM Standards: D618, Standard Practice for Conditioning Plastics for Testing D638, Standard Test Method for Tensile Properties of Plastics D792, Test Methods for Density and Specific Gravity (Relative Density) of Plastics by Displacement D883, Standard Terminology Relating to Plastics D1238, Test Method for Melt Flow Rates of Thermoplastics by Extrusion Plastometer D1505, Test Method for Density of Pl astics by the Density-Gradient Technique D2122, Standard Test Method for Determining Dimensions of Thermoplastic Pipe and Fittings D2412, Standard test Method for Determination of External Loading Characteristics of Plastic Pipe by Parallel-Plate Loading D2444, Standard Test Method for Determination of the Impact Resistance of Thermoplastic Pipe and Fittings by Means of a Tup (Falling Weight) D3212, Standard Specification for Joints for Drain and Sewer Plastic Pipes Using Flexible Elastomeric Seals D3350, Standard Specification for Polyethylene Plastics Pipe and Fittings Materials D3895, Standard Test Method for Oxidative-Induction Time of Polyolefins by Differential Scanning Calorimetry D4218, Standard Test Method for Determination of Carbon-Black Content in Polyethylene Compounds By the Muffle-Furnace Technique. D4703, Practice for Compression Molding Thermoplastic Materials into Test Specimens, Plaques, or Sheets D5630, Test Method for Ash Content in Plastics F412, Standard Terminology Relating to Plastic Piping Systems F477, Standard Specification for Elastomeric Seals (Gaskets) for Joining Plastic Pipe F2136, Standard Test Method for Notched Constant Ligament-Stress (NCLS) Test to Determine Slow-Crack-Growth Resistance of HDPE Resins or HDPE Corrugated Pipe 3. TERMINOLOGY 3.1. The terminology used in this standard is original to this standard, unless otherwise noted. 3.2. Buckling any reverse curvature or deformation in the pipe wall that reduces the load-carrying capability of the pipe. Any decrease or downward deviation in the pipe stiffness test curve shall be considered a wall-buckling point. 3.3. Crack any narrow opening or fissure in the surface that is visible to the naked eye. (ASTM F412) 3.4. Crease an irrecoverable indentation, generally associated with wall buckling. 3.5. Delamination--A separation between the inner liner and outer corrugated wall of Type S pipe as evidenced by a visible gap extending completely through at least one corrugation valley at any point around the circumference of the pipe. For Type D pipe, delamination is a separation of the

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I-4 inner and outer wall as evidenced by a visible gap extending completely between the internal supports and inner or outer wall at any point around the circumference of the pipe. 3.6. Mixed-color PCR-HDPE Post-Consumer Recycled HDPE that is composed of mostly colored detergent bottles. 3.7. Polyethylene (PE) plastics plastics based on polymers made with ethylene as essentially the sole monomer (ASTM D883). 3.8. Post-consumer recycled HDPE (PCR-HDPE) Polyethylene that has been discarded by consumers after use, then collected, cleaned and washed. The density is greater than 0.940 g/cm3 and typical sources include primarily bottles and some bags. 3.9. Post-industrial recycled HDPE (PIR-HDPE) Polyethylene that has been obtained for recycling from industrial sources. This may include industrial scrap, rejected parts, or surplus goods. 3.10. Reprocessed PCR-HDPE Post-Consumer Recycled HDPE that has been cleaned, washed, melt- filtered, and pelletized. Commonly known as "Repro." 3.11. Reworked plastic A plastic from a processor's own production that has been reground, pelletized, or solvated after having been previously processed by molding, extrusion, etc. (ASTM D883). 3.12. Virgin polyethylene material PE plastic material in the form of pellets, granules, powder, floc, or liquid that has not been subject to use or processing other than required for initial manufacture. 3.13. Slow crack growth A phenomenon by which a stress crack may form. A stress crack is an external or internal crack in plastic caused by tensile stresses less than its short-time mechanical strength. 4. CLASSIFICATION 4.1. The corrugated polyethylene pipe covered by this specification is classified as follows: 4.1.1. Type C This pipe shall have a full circular cross section, with a corrugated surface both inside and outside. Corrugations shall be annular. 4.1.1.1. Type CP This pipe shall be Type C with perforations. 4.1.2. Type S This pipe shall have a full circular cross section, with an outer corrugated pipe wall and a smooth inner liner. Corrugations shall be annular. 4.1.2.1. Type SP This pipe shall be Type S with perforations. 4.1.3. Type D This pipe shall consist of an essentially smooth inner wall/liner braced circumferentially or spirally with projections or ribs joined to an essentially smooth outer wall. 4.1.3.1. Type DP This pipe shall be Type D with perforations. 4.2. Two classes of perforations are as described in Sections 7.3.1 and 7.3.2.

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I-5 5. ORDERING INFORMATION 5.1. Orders using this specification shall include the following information as necessary to adequately describe the desired product: 5.1.1. AASHTO designation and year of issue; 5.1.2. Type of pipe (Section 4.1); 5.1.3. Diameter and length required, either total length or length of each piece and number of pieces; 5.1.4. Number of couplings; 5.1.5. Class of perforations (Class 2 is furnished if not specified) (Section 7.3); and 5.1.6. Certification, if desired (Section 12.1). 6. MATERIALS 6.1. Basic Materials: 6.1.1. Extruded Pipe Pipe shall be made from resin compounds that meet the requirements shown in Table 1. Compliance with the standard can be obtained by testing either the resin or the pipe. In case of disputes, all tests will be performed on compression molded plaques from the pipe. The pipe requirements are the same as the resin except for the break strain and the NCLS stress crack resistance, which can be reduced when a plaque is made from the pipe instead of the resin. Pipe samples are commonly exposed to dust and dirt that can compromise these properties. 6.1.2. Table 1. Required properties for corrugated polyethylene pipe containing recycled polyethylene. Property Test Method Required Value Density ASTM D1505 >0.947-0.955a g/cm ASTM D792 Melt Index ASTM D1238 <0.4 g/10 min 190C/2.16 Kg % Carbon Black ASTM D4218 2-4 % % Ash ASTM D5603 <0.5 % % PP DSC <5.0 % Section 9.6 Yield Stress ASTM D638b >3500 psi Break Strain ASTM D638c >200% resin >150% pipe NCLS Stress ASTM F2136 36 hrs resin Crack Test 30 hrs pipe BFF Stress Section 9.9 200 hrs Crack Test 80C/650 psi OIT ASTM D3895 50 mind a Correct for carbon black by Dcor = D 0.0044C, where C is % carbon black. b Strain rate shall be 2.0" per minute. c Assume 2.0" gage length. d A common additive package that meets this requirement is 1000 ppm Irganox 1010 plus 1000 ppm Irgaphos 168, available from Ciba-Geigy.

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I-6 6.1.3. Blow Molded Fittings Fittings shall be made of virgin PE resin compounds meeting the requirements of ASTM D3350 and cell classification 435400C, except that the carbon black content shall not be less than two percent but does not exceed five percent, and the density shall not be less than 0.948 gm/cc nor greater than 0.955 gm/cc. Resins that have higher cell classifications in one or more properties, with the exception of density, are acceptable provided product requirements are met. For slow-crack-growth resistance, acceptance of resins shall be determined by using the Notched Constant Ligament-Stress (NCLS) test according to the procedure described in Section 9.8. For slow-crack-growth resistance, acceptance of pipe shall be determined by tests on finished pipe using the Notched Constant Ligament-Stress (NCLS) test according to the procedure described in Section 9.8 The average failure time of the pipe liner shall not be less than 18 hours. Note: If profile geometries do not have a flat portion of sufficient length to produce an NCLS tensile specimen, the pipe sample should be ground and a test plaque made in accordance with ASTM D1928 and tested per ASTM F2136. The av erage failure time of the test specimens from plaques shall not be less than 24 hours. 6.1.4. Rotational Molded Fittings and Coupling s Fittings and couplings shall be made of virgin PE resins meeting the requirements of ASTM D3350 and cell classification 213320C, except that the carbon-black content shall not be less than two percent but does not exceed five percent. Resins that have higher cell classifications in one or more properties are acceptable provided product requirements are met. 6.1.5. Injection Molded Fittings and Couplings Fittings and couplings shall be made of virgin PE resins meeting the requirements of ASTM D3350 and cell classification 314420C, except that the carbon-black content shall not be less than two percent but does not exceed five percent. Resins that have higher cell classifications in one or more properties are acceptable provided product requirements are met. 6.2. Reworked Plastic In lieu of virgin PE, clean reworked plastic may be used by the manufacturer, provided that it meets the cell class requirements as described in Section 6.1. 6.3. Resin Blending When blended resins are used, the components of the blend must be virgin PE and the final blend must meet all of the requirements of Section 6.1.1 for extruded pipe and blow molded fittings, Section 6.1.3 for rotational molded fittings and couplings, and Section 6.1.5 for injection molded fittings and couplings. 7. REQUIREMENTS 7.1. Workmanship The pipe and fittings shall be free of foreign inclusions and visible defects as defined herein. The ends of the pipe shall be cut squarely and cleanly so as not to adversely affect joining or connecting. 7.1.1. Visible Defects--Cracks, creases, delaminations, and unpigmented or nonuniformly pigmented pipe are not permissible in the pipe or fittings as furnished. There shall be no evidence of delamination when tested in accordance with Section 9.16. 7.2. Pipe Dimensions:

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I-7 7.2.1. Nominal Size--The nominal size for the pipe and fittings is based on the nominal inside diameter of the pipe. Nominal diameters shall be 300, 375, 450, 525, 600, 675, 750, 900, 1050, 1200, 1350, and 1500 mm. 7.2.2. Wall Thickness--The inner wall of Type S pipe, and both inner and outer walls of Type D pipe, shall have the following minimum thicknesses, when measured in accordance with Section 9.15.4: Diameter, mm Wall Thickness, mm 300 0.9 375 1.0 450 1.3 525 1.5 600 1.5 675 1.5 750 1.5 900 1.7 1050 1.8 1200 1.8 1350 2.0 1500 2.0 7.2.3. Inside Diameter Tolerances--The tolerance on the specified inside diameter shall be 4.5 percent oversize and 1.5 percent undersize, but not more than 37 mm oversize when measured in accordance with Section 9.15.1. 7.2.4. Length--Corrugated PE pipe may be sold in any length agreeable to the user. Lengths shall not be less than 99 percent of the stated quantity when measured in accordance with Section 9.15.2. 7.3. Perforations--When perforated pipe is specified, the perforations shall conform to the requirements of Class 2, unless otherwise specified in the order. Class 1 perforations are for pipe intended to be used for subsurface drainage or combination storm and underdrain. Class 2 perforations are for pipe intended to be used for subsurface drainage only. The perforations shall be cleanly cut so as not to restrict the inflow of water. Pipe connected by couplings or bands may be unperforated within 100 mm of each end of each length of pipe. Pipe connected by bell and spigot joints may not be perforated in the area of the bells and spigots.

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I-8 Figure 1. Requirements for perforations. Table 2. Rows of perforations, height H of the centerline of the uppermost rows above the invert, and chord length L of unperforated segment, for Class 1 perforations. Nominal Diameter, mm Rows of Perforationsa H, Max,b mm L, Min,b mm 300 6 138 192 375 6 172 240 450 6 207 288 525 6 241 336 c c 600 and 8 larger a Minimum number of rows. A greater number of rows for increased inlet area shall be subject to agreement between purchaser and manufacturer. Note that the number of perforations per meter in each row (and inlet area) is dependent on the corrugation pitch. b See Figure 1 for location of dimensions H and L. c H(max) = 0.46D; L(min) = 0.64D, where D = nominal diameter of pipe, mm. 7.3.1. Class 1 Perforations The perforations shall be circular and shall have nominal diameters of at least 5 mm but not greater than 10 mm and shall be arranged in rows parallel to the axis of the pipe. For Type CP and SP pipe, the perforations shall be located in the external valleys with perforations in each row for each corrugation. (The perforations shall not cut into the corrugation sidewalls.) For Type DP pipe, perforations shall be located in the center of the cells. The perforations shall not cut into the vertical sections of the cells. The rows of perforations shall be arranged in two equal groups placed symmetrically on either side of the lower unperforated segment corresponding to the flow line of the pipe. The spacing of the rows shall be uniform. The distance between the centerlines of the rows shall not be less than 25 mm. The minimum number of longitudinal rows of perforations, the maximum height of the centerlines of the uppermost rows of perforations above the bottom of the invert, and the inside chord lengths of the unperforated segments illustrated in Figure 1 shall be as specified in Table 2.

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I-9 7.3.2. Class 2 Perforations Circular perforations shall be a minimum of 5 mm and shall not exceed 10 mm in diameter. The width of slots shall not exceed 3 mm. The length of slots shall not surpass 70 mm for 300-mm and 375-mm pipe and 75-mm for 450-mm and larger pipe. Perforations shall be placed in the external valleys for Type CP and SP pipe and in the center of the cells for Type DP pipe. Perforations shall be uniformly spaced along the length and circumference of the pipe. The water inlet area shall be a minimum of 30 cm2/m for pipe sizes 300 to 450 mm and 40 cm2/m for pipe sizes larger than 450 mm. All measurements shall be made in accordance with Section 9.15.3. 7.4. Density The density, measured on a piece of the pipe or a plaque compression molded from the pipe shall be between 0.947 and 0.955 g/cm 3 when tested according to ASTM D792 or D1505, and Section 9.2 of this standard. 7.5. Melt Index The melt index (MI), measured on a piece of the pipe or a plaque made from the pipe shall be < 0.4 g/10 min., when tested according to ASTM D1238 and Section 9.3 of this standard. 7.6. % Carbon Black The % carbon black, measured on a piece of the pipe or a plaque made from the pipe will be between 2 and 4%, when tested according to ASTM D4218 and Section 9.4 of this standard. 7.7. % Ash - The percentage ash, measured on a piece of the pipe or a plaque made from the pipe shall be <0.5%, when tested according to ASTM D5603 and Section 9.5 of this standard. 7.8. % Polypropylene The % PP, measured on a piece of the pipe or a plaque made from the pipe shall be <5.0% when tested according to Section 9.6 of this standard. 7.9. Yield Stress The yield stress shall be >3500 psi when tested according to ASTM D638 and section 9.7 of this standard. 7.10. Break Strain The break strain shall be >200% on a plaque made from the resin and >150% on a plaque made from the pipe when tested according to ASTM D638 and section 9.7 of this standard. 7.11. NCLS Stress-Crack Resistance The resistance to slow-crack growth in the presence of a face notch shall be >36 hrs on a plaque made from the resin and >30 hrs on a plaque from the pipe, when tested according to ASTM F2136 and Section 9.8 of this standard. 7.12. BFF Stress-Crack Resistance The resistance to slow-crack growth in the absence of a face notch shall be >200 hrs when tested according to Section 9.9 of this standard. 7.13. Oxidative Induction Time (OIT) The OIT shall be >50 minutes when tested according to ASTM D3895 and Section 9.10 of this standard. 7.14. Pipe Stiffness--The pipe shall have a minimum pipe stiffness at five percent deflection as follows when tested in accordance with Section 9.11: Diameter, mm Pipe Stiffness, kPa 300 345 375 290 450 275 525 260 600 235 750 200

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I-10 900 160 1050 150 1200 140 1350 125 1500 110 7.15. Pipe Flattening--There shall be no evidence of wall buckling, cracking, splitting, delamination or decrease or downward deviation in the load-deflection curve when the pipe is tested in accordance with Section 9.12. 7.16. Brittleness--Pipe specimens shall not crack or split when tested in accordance with Section 9.13. Five non-failures out of six impacts will be acceptable. 7.17. Fitting Requirements: 7.17.1. The fittings shall not reduce or impair the overall integrity or function of the pipe line. 7.17.2. Common corrugated fittings include in-line joint fittings; such as couplings and reducers, and branch or complimentary assembly fittings; such as tees, wyes, and end caps. These fittings are installed by various methods. 7.17.3. All fittings shall be within an overall length dimensional tolerance 12 mm of the manufacturer's specified dimensions when measured in accordance with Section 9.15.2. 7.17.4. Fittings shall not reduce the inside diameter of the pipe being joined by more than 12 mm. Reducer fittings shall not reduce the cross-sectional area of the small size. 7.17.5. Couplings shall be corrugated to match the pipe corrugations and shall provide sufficient longitudinal strength to preserve pipe alignment and prevent separation at the joints. Couplings shall be bell and spigot or split collar. Split couplings shall engage at least two full corrugations on each pipe section. 7.17.6. The design of the fittings shall be such that when connected with the pipe, the axis of the assembly will be level and true when tested in accordance with Section 9.14.1. 7.17.7. Other types of coupling bands or fastening devices which are equally effective as those described, and which comply with the joint performance criteria of AASHTO's LRFD Bridge Construction Specifications, Section 26, may be used when approved by the purchaser. 7.18. Only fittings supplied or recommended by the pipe manufacturer should be used. Fabricated fittings should be supplied with joints compatible with the overall system. All joints shall meet the requirements of a Soiltight Joint unless otherwise specified by the owner/designer. 7.18.1. Soiltight joints are specified as a function of opening size, channel length, and backfill particle size. If the size of the opening exceeds 3 mm, the length of the channel must be at least four times the size of the opening. A backfill material containing a high percentage of fine-graded soils requires investigation for the specific type of joint to be used to guard against soil infiltration. Information regarding joint soiltightness criteria can be found in AASHTO's LRFD Bridge Construction Specifications, Section 26, "Metal Culverts."

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I-11 7.18.2. Silt-tight joints should be used where the backfill material has a high percentage of fines. Silt-tight bell and spigot joints will utilize an elastomeric rubber seal meeting ASTM F477. Silt-tight joints must be designated to pass a laboratory pressure test of at least 14 kPa (2.0 psi). 7.18.3. Watertight joints must meet a 74 kPa (10.7 psi) laboratory test per ASTM D 3212 and utilize a bell and spigot design with a gasket meeting ASTM F477. 8. CONDITIONING 8.1. Conditioning Condition the specimen prior to test at 21 to 25C for not less than 24 hours in accordance with Procedure A in ASTM D618 for those tests where conditioning is required, and unless otherwise specified. 8.2. Conditions Conduct all tests at a laboratory temperature of 21 to 25C unless otherwise specified herein. 9. TEST METHODS 9.1. Test Conditions Unless otherwise specified in the test methods or in this specification, conduct tests at the standard laboratory temperature of 23 2C (73.4 3.6F). 9.2. Density Test methods ASTM D1505 or D792 are acceptable. Make three separate determinations using separate pellets or separate portions of a plaque. The plaque thickness shall be 1.9 0.08 mm (0.075 .003 in.). Calculate and report the average and standard deviation from the mean. Correct the density value for % carbon black by subtracting 0.0044 g/cm3 for each percent of carbon black. 9.3. Melt Index Test method ASTM D1238, using Condition 190/2.16. Make duplicate determinations on either pellets or a plaque and calculate the average. 9.4. % Carbon Black Test method ASTM D4218 with 1g samples. Make duplicate determinations on either pellets or a plaque and calculate the average. 9.5. % Ash - Test method ASTM D5630, Procedure B. 9.5.1. Porcelain crucibles shall be used. 9.5.2. Sample size shall be 1g. 9.5.3. Heat at least 10 minutes at 800C. 9.6. % Polypropylene 9.6.1. Generate a melting curve by differential scanning calorimetry (DSC) at a heating rate of 10C/min from room temperature to 200C. See Figure 2.

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I-12 0 -1 Heat Flow (W/g) -2 -3 -4 20 40 60 80 100 120 140 160 180 200 Exo Up Temperature (C) Universal V4.5A TA Instruments Figure 2. DSC curve of HDPE containing PP generated. 9.6.2. Expand the curve to a range that includes the end of the HDPE peak and the complete PP peak. See Figure 3. -0.56 150.59C -0.58 2.568J/g 142.71C -0.60 Heat Flow (W/g) -0.62 162.84C -0.64 -0.66 130 140 150 160 170 180 Exo Up Temperature (C) Universal V4.5A TA Instruments Figure 3. DSC curve of HDPE containing PP expanded. 9.6.3. Integrate the curve from a flat point before the PP melting to a point where the PP curve returns to baseline. 9.6.4. The point where the HDPE melt returns to baseline shall be marked. The end of the HDPE melt and the beginning of the PP melt will not necessarily be the same point. 9.6.5. Record the HDPE end-of-melt temperature and the PP heat of fusion in J/g. 9.6.6. Calculate the theoretical heat of fusion for 100% polypropylene for the portion of the PP melting curve that does not overlap with HDPE by: Y = -0.035X2 + 8.851X 475.6 (1) Where: X = HDPE end-of-melt temperature (C)

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I-13 And Y = Hf of 100% PP not overlapped with HDPE. For X = 142.7, Y = 74.7 J/g. 9.6.7. Calculate the percentage PP by: %PP = Hf of sample/ Hf of 100% PP x 100 For Hf of sample = 2.57 J/g, %PP = 2.57/74.7 x 100 = 3.4% 9.6.8. Test two specimens from different parts of the molded plaque and report the average. 9.7. Yield Stress/Break Strain Test by ASTM Method D638, with a Type IV dumbbell at 2"/min crosshead speed. 9.7.1. Test five specimens, individually measured for thickness. 9.7.2. 2.0-in. gage length, use crosshead to follow displacement. 9.7.3. Report five results, average, and standard deviation. 9.8. NCLS Stress-Crack Test Test 1.9-mm plaque for slow-crack growth with ASTM F2136 with a notch depth of 20% of the test specimen thickness and under an applied load of 4100 kPa (600 psi). 9.8.1. Test five replicates and report the average and standard deviation. 9.9. BFF Stress-Crack Test This test is performed with the use of common stress-crack frames in deionized water at 80C (176F), under an applied stress of 650 psi. 9.9.1. A bath that has never contained Igepal or other surfactants is preferred. Residual surfactant can dramatically accelerate the test and is very difficult to remove. 9.9.2. Prepare a compression molded plaque that is a minimum of 15.24 cm x 15.24 cm (6 in. x 6 in.) and has a center section, that is 84-mm wide and 1.14-mm thick (3.3 in. x 0.045 in.), end sections that are 19-mm wide and 2.29-mm thick (0.75 in. x 0.09 in.) and two sections 16.5-mm wide that transitions from 1.14-mm to 2.29-mm thick. 9.9.3. The test specimen is a ASTM D638 Type I Dumbbell with two modifications. First, drill a 7/32" hole into each head portion so that the specimens can be mounted with a screw in a conventional stress-crack testing device. However, because of the holes, the tabs on each side of the hole are narrower than the reduced section of the dumbbell. Therefore, the highest stressed areas are the tabs, so all the specimens would naturally fail at the tabs. To circumvent this limitation, a 6" square open faced mold was modified to produce plaques that were about 45 mil in the center and over 90 mil on the edges. This way, the tabs are under less stress than the reduced section so nearly all of the failures occur in the reduced section. A drawing of the fathead test specimen is shown in Figure 4. Notice that only the mold cavity needs modification, the top plate of the mold remains flat.

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I-14 Figure 4. Fathead specimen. 9.9.4. The test device is manufactured by BT Technology and is shown in Figure 5. The weight tubes were modified to allow for the higher loads used in this test. 9.9.5. Five replicates are tested and the average and standard deviation reported. Figure 5. BFF test device. 9.10. Oxidative Induction Time (OIT) Test by ASTM D3895 at 200C in oxygen in duplicate and report the average time. 9.11. Pipe Stiffness Select a minimum of two pipe specimens and test for pipe stiffness (PS), as described in ASTM D2412 except for the following: (1) the test specimens shall be a minimu m of one diameter length; (2) locate the first specimen in the loading machine with an imaginary line connecting the two seams formed by the corrugation mold (end view) parallel to the loading plates, when applicable. The specimen must lie flat on the plate within 3 mm and may be straightened by hand bending at room temperature to accomplish this. Use the first location as a reference point for rotation and testing of the other specimen. Rotate the pipe 90 degrees from the first orientation and test. Test each specimen in one position only; (3) the deflection indicator shall be readable and accurate to 0.02 mm; (4) the residual curvature found in tubing frequently results in an erratic initial load/deflection curve. When this occurs, the beginning point for deflection measurement shall be at a load of 20 5 N. The point shall be considered as the origin of the load deflection curve. (5) The crosshead speed shall be the faster of 12.7 mm per minute (0.5 in. per minute) or 2% of the nominal inside diameter per minute. Note 2--The parallel plates must exceed the length of the test specimen as specified above.

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I-15 Note 3--Additional pipe specimens may be tested at other orientations for pipe stiffness and flattening if desired. 9.12. Pipe Flattening Flatten the two-pipe specimens fro m Section 9.11 until the vertical inside diameter is reduced by 20 percent. The rate of loading shall be the same as in Section 9.11. Examine the specimen with the unaided eye for cracking, splitting, or delamination. The specimen shall fail if wall buckling, cracking, splitting, or delamination is observed with the unaided eye or if there is a decrease or downward deviation in load-deflection curve at 20% or less deflection. The load-deflection curve shall be carried beyond 20% deflection so that the shape of the curve at 20% deflection can be determined. 9.13. Brittleness Test pipe specimens in accordance with ASTM D2444 except six specimens shall be tested, or six impacts shall be made on one specimen. In the latter case, successive impacts shall be separated by 120 10 degrees for impacts made on one circle, or at least 300 mm longitudinally for impacts made on one element. Impact points shall be at least 150 mm from the end of the specimen. Tup B shall be used, with a mass of 4.5 kg. The height of drop shall be 3.0 m. Use a flat plate specimen holder. Condition the specimens for 24 hours at a temperature of 4 2C, and conduct all tests within 60 seconds of removal from this atmosphere. The center of the falling tup shall strike on a corrugation crown for all impacts. 9.14. Joints and Fittings: Joint Integrity Pipes that have a welded bell shall be tested to verify the strength of the weld as follows: Assemble the joint in accordance with the manufacturer's recommendations. Use pipe samples at least 300 mm in length. Assemble a specimen at least 600 mm in length with the connection at the center. Load the connected pipe and joint between parallel plates at the rate of 12.5 mm per minute until the vertical inside diameter is reduced by at least 20 percent of the nominal diameter of the pipe. Inspect for damage while at the specified deflection and after load removal. 9.14.1. Alignment Assure that the assembly or joint is correct and complete. If the pipe is bent, it should be straightened prior to performing this test. Lay the assembly or joint on a flat surface and verify that it will accommodate straight-line flow. 9.15. Dimensions: 9.15.1. Inside Diameter Measure the inside diameter of the pipe with a tapered plug in accordance with ASTM D 2122. As an alternative, measure the inside diameter with a suitable device accurate to 3.0 mm by taking two inside diameter measurements, the first at the seam and the second 90 degrees from the seam, and averaging the two m easurements. The average inside diameter shall meet the requirements of Section 7.2.3. 9.15.2. Length Measure pipe with any suitable device accurate to 6.0 mm . Make all measurements on the pipe while it is stress free and at rest on a flat surface in a straight line. These measurements may be taken at ambient temperature. 9.15.3. Perforations Measure dimensions of perforations on a straight specimen with no external forces applied. Make linear measurements with instruments accurate to 0.2 mm. 9.15.4. Wall Thickness Measure the wall thickness in accordance with ASTM D2122. 9.16. Delamination Examine Type S pipe for evidence of delamination as defined and described in Section 3.5 by cutting the pipe at the corrugation crest as shown in Figure 6 and atte mpting to insert a feeler gauge between the inner and outer corrugated wall at the corrugation valley as

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I-16 shown in Figure 6. The feeler gauge should not pass through the corrugation valley into a void at any location along the circumference of the pipe. Examine Type D pipe for evidence of delamination as defined and described in Section 3.5 by cutting a section through the pipe as shown in Figure 6 and attempting to insert a feeler gauge between the internal supports and the inner and outer walls as shown in Figure 7. The feeler gauge should not pass between the internal support and the inner or outer wall at any point along the circumference of the pipe. Figure 6. Location of pipe cut.

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I-17 Figure 7. Feeler gauge insertion. 10. INSPECTION AND RETEST 10.1. Inspection Inspection of the material shall be made as agreed upon by the purchaser and the seller as part of the purchase contract. 10.2. Retest and Rejection If any failure to conform to these specifications occurs, the pipe or fittings may be retested to establish conformity in accordance with agreement between the purchaser and seller. Individual results, not averages, constitute failure. 11. MARKING 11.1. All pipe shall be clearly marked at intervals of no more than 3.5 m as follows: 11.1.1. Manufacturer's name or trademark; 11.1.2. Nominal size; 11.1.3. This specification designation, M 294Recycled; 11.1.4. The percentage recycled content; 11.1.5. The plant designation code; and

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I-18 11.1.6. The date of manufacture or an appropriate code. If a date code is used, a durable manufacturer sticker that identifies the actual date of manufacture shall be adhered to the inside of each length of pipe. Note 5--A durable sticker is one that is substantial enough to remain in place and be legible through installation of the pipe. 11.2. Fittings shall be marked with the designation number of this specification, M 294, and with the manufacturer's identification symbol. 12. QUALITY ASSURANCE 12.1. A manufacturer's certificate that the product was manufactured, tested, and supplied in accordance with this specification, together with a report of the test results, and the date each test was completed, shall be furnished upon request. Each certification furnished shall be signed by a person authorized by the manufacturer. Manufacturer Records-Manufacturers shall keep records of the following: (1) resin manufacturers data sheets and certification that the base resin meets minimum cell class requirements of the product specification; (2) manufacturer's data sheets and quantities for all additives blended with the resin by the pipe manufacturer; (3) test results to demonstrate that, if resins of two different cell classifications are blended, the resulting mixture meets the requirements of the specified cell classification; (4) correlation of resin shipment source with pipe markings. ANNEX (Mandatory Information) A1. GUIDELINES FOR PIPE MADE FROM BLENDED RESINS A1.1.1. If pipe is made from a blend of component resins or from off-prime resin or blends, the manufacturer of each component resin should supply a certificate of analysis for each lot that includes the lot specific melt index and density. The pipe manufacturer should have a resin testing program in place that includes the testing of each resin blend lot for density and melt index and have the means of conducting (in-house or contract lab) the remaining cell class and NCLS testing as specified in this standard. The manufacturer shall test each resin or resin blend lot for full cell class, NCLS and IT, unless a regular quality assurance program is in place to correlate cell class results to density and melt index. In any case, full cell class and NCLS testing should be performed on all approved/certified resin blends at least quarterly. Additionally, the pipe manufacturer shall have the resin blend independently tested and pre-qualified based on a "recipe" with component percentage tolerances of no more than plus or minus 1.5% substantiated by independent testing. A1.1.2. When blends of resins are used for pipe manufacture, the final blended resin must meet the requirements of the standard. It is not necessary for the individual components of the blend to meet the cell class or NCLS requirements of this standard, provided that the final blend meets all the requirements. A1.1.3. Sampling and testing of the final blended resin shall be performed as follows: A1.1.3.1. The sample shall be prepared either by direct sampling from the feed hopper of the extruder (after the material has already been weigh-blended by the blenders or other means), or by manually weigh blending the individual components to the specified finished blend ratios. The manufacturer shall have current calibration records for the automated or manual weigh-blending equipment.

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I-19 A1.1.3.2. The blended sample shall not contain carbon black concentrate. If carbon black concentrate is present in the sampled material, the carbon black concentrate shall be removed prior to further sample preparation. A1.1.3.3. The dry-blended sample shall be fully homogenized by melt blending via a twin screw lab extruder prior to testing for physical properties. A1.1.3.4. The melt-blended sample shall be tested for melt index, density, and NCLS in accordance with the amount of hours per the requirements of the standard. APPENDIX (Nonmandatory Information) X1. QUALITY CONTROL/QUALITY ASSURANCE PROGRAM X1.1. Scope: X1.1.1. As required in Sections 10 and 12, the acceptance of these products relies on the adequate inspection and certification agreed to between the buyer and the seller/producer. This appendix should serve as a guide for both the manufacturer and the user. It places the responsibility on the producer to control the quality of the material they produce and to provide the quality control information needed for acceptance by the buyer/user. The producer is required to perform quality control sampling, testing and record-keeping on materials they ship. It also sets forth quality assurance sampling, testing and record keeping that should be performed by the buyer/user to confirm the performance of the producer's control plan. X1.2. Program Requirements: X1.2.1. The producing company must have a quality control plan approved by the specifying agency. X1.2.2. The producing plant must have an approved quality control plan. X1.2.3. The plant must have an approved laboratory, either within the company or an independent laboratory. X1.2.4. The producing plant(s) must have a designated quality control technician(s). X1.3. Quality Control Plan: X1.3.1. The producer must supply to the specifying agency a written quality control plan that shows how the producer will control the equipment, materials, and production methods to insure that the specified products are supplied. The following information must be included in the plan: X1.3.1.1. Titles of the personnel responsible for production quality at the plant(s); X1.3.1.2. The physical location of the plant(s); X1.3.1.3. The methods of identification for each lot of material during manufacturer, testing, storage, and shipment. The method of identification shall allow the specifying agency to trace the finished product to the material provider;

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I-20 X1.3.1.4. The method of sampling and testing of raw materials and of finished product, including lot sizes and types of tests performed; and X1.3.1.5. A plan for dealing with nonconforming product, including how the producer plans to initiate immediate investigation and how corrective action will be implemented to remedy the cause of the problem. X1.4. Approved Laboratory: X1.4.1. All tests must be conducted at laboratories approved by the specifier. Each manufacturer may establish and maintain its own laboratory for performance of quality control testing or may utilize an approved independent laboratory. Records of instrument calibration and maintenance and sample collection and analysis must be maintained at the laboratory. X1.5. Quality Control Technician: X1.5.1. All samples must be taken and tested by the quality control technician(s) designated by the producer. The designated quality control technician(s) will be responsible for overall Quality Control at the producing plant. X1.6. Annual Update: X1.6.1. An annual update may be required. The annual update may be submitted by the manufacturer to the specifying agency by December 31st of each calendar year. X1.7. Plant Approval: X1.7.1. The plant approval process requires the manufacturer to submit an annual update to the specifying agency. The update must identify the specific product manufactured at the plant. X1.7.2. The specifying agency will review the manufacturer's written quality control plan and a plant inspection may be scheduled. This inspection will verify that the quality control plan has been implemented and is being followed and that at least one designated quality control technician is on-site and will be present when material is being produced under this program. The laboratory will be inspected and approved if it meets the requirements. X1.8. Sampling and Testing: X1.8.1. The quality assurance plan approved for each manufacturer, and/or manufacturer's location, shall detail the methods and frequency of sampling and testing for all raw materials and products purchased or manufactured at that location. All testing shall be in accordance with current specifications and procedures referenced in M294. X1.8.2. Samples of materials and pipe may be taken by the specifying agency. X1.8.3. The specifying agency may require an annual third-party independent assurance test. X1.9. Sample Identification and Record Keeping: X1.9.1. Manufacturer's Quality Control samples are to be uniquely identified by the producing plant. X1.9.2. Quality Control and Quality assurance data is to be retained by the manufacturer for two years and made available to the specifying agency upon request.

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I-21 X1.9.3. Quality Control test reports shall include the lot identification. X1.9.4. Unless requested at the time of ordering, test reports do not have to be filed for specific projects. X1.9.5. Reports shall indicate the action taken to resolve nonconforming product.