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H-1 APPENDIX H Proposed Draft Standard Specification for Corrugated Polyethylene Drainage Pipe Containing Recycled Polyethylene, 75- to 250-mm Diameter

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H-2 DRAFT ____________________________________________________________ Draft Standard Specification for Corrugated Polyethylene Drainage Pipe Containing Recycled Polyethylene, 75- to 250-mm Diameter AASHTO Designation: M252-Recycled-XX 1. SCOPE 1.1. This specification covers the requirements and methods of test for corrugated polyethylene (PE) pipe, couplings, and fittings for use in subsurface drainage systems, storm sewers, and in surface drainage (culverts), where soil support is given to the pipe's flexible walls in all applications. 1.1.1. This standard allows for the use of recycled polyethylene in the pipe, but not in the couplings or the fittings. 1.1.2. Nominal sizes of 75 to 250 mm are included. 1.1.3.Material properties, dimensions, pipe stiffness, perforations, joining systems and forms of marking are specified. Note 1--When polyethylene pipe is to be used in locations where the ends may be exposed, consideration should be given to combustibility of the polyethylene and the deteriorating effects of prolonged exposure to ultraviolet radiation. 1.2. 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 Standard: R 16, Regulatory Information for Chemicals Used in AASHTO Tests 2.2. ASTM Standards: D618, Method for Conditioning Plastics and Electrical Insulating Materials for Testing D638, Test Method for Tensile Properties of Plastics D792, Test Methods for Density and Specific Gravity (Relative Density) of Plastics by Displacement

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H-3 D883, Definition of Terms Relating to Plastics D1238, Test Method for Melt Flow Rates of Thermoplastics by Extrusion Plastometer D1505, Test Method for Density of Plastics by the Density-Gradient Technique D2122, Method of Determining Dimensions of Thermoplastic Pipe and Fittings D2412, Test Method for Determination of External Loading Characteristics of Plastic Pipe by Parallel-Plate Loading 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, Definitions of Terms Relating to Plastic Piping Systems 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. Crack any narrow opening or fissure in the surface that is visible to the naked eye. (ASTM F412) 3.3. Crease An irrecoverable indentation; generally associated with wall buckling. (AASHTO M252) 3.4. Mixed-Color PCR-HDPE Post-Consumer Recycled HDPE that is composed of mostly colored detergent bottles. 3.5. 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. 3.6. 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.

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H-4 3.7. Reprocessed PCR-HDPE Post-Consumer Recycled HDPE that has been cleaned, washed, melt-filtered, and pelletized. Commonly known as "Repro." 3.8. Reworked Material 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). 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 may be either annular or helical. 4.1.1.1. Type CP This pipe shall be Type C with Class 2 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 may be either annular or helical. Type S pipe is not available in nominal sizes of less than 100 mm. 4.1.2.1. Type SP This pipe shall be Type S with either Class 1 or Class 2 perforations. 4.2. Class 1 and Class 2 perforations are as described in Sections 7.4.1 and 7.4.2. 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; Note 2--Type C and CP pipe less than 200 mm in diameter may be supplied coiled; coiling of Type C and CP pipe 200 mm in diameter or greater is not recommended; Type S and SP pipe is not supplied in coils. 5.1.4. Number of couplings; 5.1.5. For Type SP pipe, class of perforations (Class 2 is furnished if not specified) (Section 7.4); and 5.1.6. Certification, if desired (Section 12.1).

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H-5 6. MATERIALS 6.1. Basic Materials: 6.1.1. Extruded Pipe Pipe shall be made from resin compounds that meet the material properties found 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. Table 1. Required properties for corrugated polyethylene pipe containing recycled polyethylene. Property Test Method Required Value Density ASTM D1505 0.948a g/cm ASTM D792 Melt Index ASTM D1238 <0.6 g/10 min 190C/2.16 Kg % Carbon Black ASTM D4218 2-4 % % Ash ASTM D5603 <0.75 % % PP DSC <7.5 % Section 7.6 Yield Stress ASTM D638b >3500 psi Break Strain ASTM D638c >100 % pipe NCLS Stress- ASTM F2136 >15 h pipe Crack Test OIT ASTM D3895 25 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 500 ppm Irgaphos 168, available from Ciba-Geigy. 6.1.2. Blow Molded Fittings Fittings shall be made of virgin PE resin compounds meeting the requirements of ASTM D3350 and cell classification 424420C, except that the carbon-black content shall not exceed five percent. Resins that have higher cell classifications in one or more properties are acceptable provided product requirements are met.

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H-6 6.1.3. Rotational Molded Fittings and Couplings 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 exceed five percent. Resins that have higher cell classifications in one or more properties are acceptable provided product requirements are met. 6.1.4. 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 exceed five percent. Resins that have higher cell classifications in one or more properties are acceptable provided product requirements are met. 6.2. Reworked Material In lieu of virgin PE, clean reworked material may be used, provided that it meets the cell class requirements as described in Section 6.1. 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, unpigmented, or nonuniformly pigmented pipe are not permissible. 7.1.2. Inner Liner For Type S and SP pipe, the inner liner shall be fused to the outer corrugated wall at all internal corrugation crests. 7.2. Pipe Dimensions: 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 sized for Type C and CP pipe in not less than 25-mm increments from 75 to 250 mm. Nominal sizes shall be sized for Type S and SP pipe in not less than 50-mm increments from 100 to 250 mm. 7.2.2. Inner Liner For Type S and SP pipe, the inner liner shall have a minimum thickness of 0.5 mm for pipe of 100 mm and 150 mm nominal size and a minimum thickness of 0.6 mm for pipe of 200 mm and 250 mm nominal size, when measured in accordance with Section 9.13.4. 7.2.3. Inside Diameter Tolerances The tolerance on the specified inside diameter shall be +4.5, 1.5 percent when measured in accordance with Section 9.13.1. 7.2.4. Length Corrugated PE pipe is an extruded product and 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 9.13.2. 7.3. Fitting and Coupling Dimensions:

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H-7 7.3.1. The maximum allowable gap between fitting or coupling and pipe shall not exceed 3 mm unless otherwise specified. 7.3.2. All fittings and couplings shall be within an overall length dimensional tolerance of 12 mm of the manufacturer's specified dimensions. 7.4. 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. Where circular perforations are preferred, the drill shall not penetrate the side walls of the corrugations. Pipe connected by couplings or bands may be unperforated within 100 mm of each end of each length of pipe. Note 3--Pipe ordered under Class 1 perforations has no requirement as to inlet area because it specifies size, number, and location of holes. Alternate perforation patterns should be agreed to between the purchaser and manufacturer. 7.4.1. Class 1 Perforations The perforations shall be approximately circular and shall have nominal diameters of not more than 5 mm for 100- and 150-mm diameter pipe and not greater than 10 mm for 200- and 250-mm diameter pipe. The holes shall be arranged in rows parallel to the axis of the pipe. The location of the perforations shall be in the valley of the outside corrugation and in each corrugation. 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 of the centerlines of the uppermost rows 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. All measurements shall be made in accordance with Section 9.13.3. 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, Rows of H, Max,b mm L, Min,b mm mm Perforationsa 75 2 35 50 100 2 45 65 150 4 70 95 200 4 94 130 250 4 120 160 a Minimum number of rows. A greater number of rows for increased inlet area shall be subject to agreement between purchaser and manufacture. 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.

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H-8 Figure 1. Requirements for perforations. 7.4.2. Class 2 Perforations--Circular and slotted perforations shall conform to the maximum dimensions as shown in Table 3. Perforations shall be placed in the outside valleys of the corrugations. The water inlet area shall be a minimum of 20 cm2/m of pipe. All measurements shall be made in accordance with Section 9.13.3. Table 3. Maximum perforation dimensions. Nominal Pipe Drilled Hole Slotted Holes Diameter, mm Diameter, mm Width, mm Length, mm 75 4.75 3 25 100 4.75 3 25 150 4.75 3 25 200 6.25 3 30 250 8.00 3 30 7.5. 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.

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H-9 7.6. 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. 7.7. % 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. 7.8. % Ash The % ash, measured on a piece of the pipe or a plaque made from the pipe shall be <0.75%, when tested according to ASTM D5603 and Section 9.5 of this standard. 7.9. % Polypropylene The % PP, measured on a piece of the pipe or a plaque made from the pipe shall be <7.5% when tested according to Section 9.6 of this standard. 7.10. Yield Stress The yield stress shall be >3500 psi when tested according to ASTM D638 and section 9.7 of this standard. 7.11. Break Strain The break strain shall be >100% when tested according to ASTM D638 and section 9.7 of this standard. 7.12. NCLS Stress-Crack Resistance The resistance to stress cracking shall be >15 h, when tested according to ASTM F2136 and Section 9.8 of this standard. 7.13. Oxidative Induction Time (OIT) The OIT shall be >25 minutes when tested according to ASTM D3895 and Section 9.9 of this standard. 7.14. Pipe Stiffness Type C pipe, as described in Section 4.1.1, shall have a minimum pipe stiffness (PS) of 240 kPa at five percent deflection; and Type S pipe, as described in Section 4.1.2, shall have a minimum pipe stiffness (PS) of 340 kPa at 5 percent deflection when tested in accordance with Section 9.10. The pipe tested shall contain perforations, if specified. 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 9.11. 7.16. Brittleness There shall be no cracking of the pipe wall when tested in accordance with Section 9.12 except as specified in Sections 7.16.1 and 7.16.2. Note 4--The brittleness test is similar to that described in ASTM F405. 7.16.1. Cracks with a maximum chord length of 10 mm that originate at a perforation or at either end of the sample shall not be cause for rejection. 7.16.2. Splitting along a seam or mold parting line is not caused by brittleness and should be evaluated as a workmanship defect as described in Section 7.1.1, if no split exceeds 50 mm in chord length.

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H-10 7.17. Fitting and Coupling Requirements: 7.17.1. The fittings and couplings shall not reduce or impair the overall integrity or function of the pipe line. 7.17.2. Common corrugated fittings include reducers, tees, wyes, and end caps. Note 5--Only fittings and couplings supplied or recommended by the pipe manufacturer should be used. 7.17.3. Fittings and couplings shall not reduce the inside diameter of the pipe being joined by more than five percent of the nominal inside diameter. Reducer fittings shall not reduce the cross-sectional area of the smaller size. 7.17.4. Pipe connected by in-line couplers shall not separate when tested in accordance with Section 9.14.1. 7.17.5. The coupling shall not crack or crease when tested in accordance with Section 9.14.2. 7.17.6. The design of the couplers 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 9.14.3. 8. CONDITIONING 8.1. Conditioning Condition the specimen prior to test at 23 2C for not less than 24 hours in accordance with Procedure A in ASTM D 618 for those tests where conditioning is required, and unless otherwise specified. 8.2. Condition Conduct the test in a laboratory temperature of 23 2C unless otherwise specified herein. 9. TEST METHODS 9.1. Compression Molded Plaque A plaque will be prepared in accordance with ASTM D4703 and cooled by cooling method B (15 5C per minute). The plaque thickness shall be 1.9 0.2 mm (0.075 .008 in.) 9.2. Density Test methods ASTM D1505 or D792 are acceptable. Make three separate determinations using 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 and calculate the average

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H-11 9.4. Carbon Black Content Test method ASTM D4218, with a 1g sample heated at 600C for 3 minutes. Report the average of triplicate determinations, after subtracting the average % ash from each result. 9.5. % Ash - Test method ASTM D5630, Procedure B. A 1g sample heated at 800C for 10 minutes in a porcelain crucible. Report the average of triplicate determinations. 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. 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. The curve shall be expanded 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.

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H-12 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. Mark the point where the HDPE melt returns to baseline. 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) 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 sample/ Hf 100% PP x 100 (2) For Hf sample = 2.57 J/g, %PP = 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 in./min crosshead speed. Measure the thickness of the five specimens separately to generate the yield stress. Assume a gage length of 2.0 in. for % Strain. Report the average and standard deviation. 9.8. NCLS Stress-Crack Test Test specimens from a 1.9 0.2 mm (0.075 0.008 in.) thick plaque for slow-crack growth by ASTM F2136 with a notch depth of 20% of the test specimen thickness and under an applied stress of 4100 kPa (600 psi). Test five replicates and report the average and standard deviation. 9.9. Oxidative Induction Time (OIT) Test by ASTM D3895 at 200C in oxygen in duplicate and report the average time. 9.10. Pipe Stiffness Select a pipe specimen and test for pipe stiffness (PS) as described in ASTM D2412, with the following exceptions. 9.10.1. The test specimen shall be 300- 10-mm long, cut to include full corrugations. 9.10.2. Locate the 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. The specimen must lie flat on the plate within 1 mm and may be straightened by hand bending at room temperature to accomplish this.

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H-13 9.10.3. The deflection indicator shall be readable and accurate to 0.03 mm. 9.10.4. The residual curvature found in corrugated pipe, especially that furnished in coils, frequently results in an erratic load/deflection curve. When this occurs, the beginning point for deflection measurements shall be at a load of 20 5 Newtons (4.5 1 lbf.). This point shall be considered as the origin of the load/deflection curve. Note 6--The parallel plates must exceed the length of the test specimen as specified above. Note 7--Additional pipe specimens may be tested at other orientations for pipe stiffness and flattening if desired. 9.11. Pipe Flattening Flatten the pipe specimen from Section 9.1 until the vertical inside diameter is reduced by 20%. The rate of loading shall be the same as in Section 9.1. 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. 9.12. Brittleness Test two samples of pipe at an impact of 45 joules between two flat parallel plates using the apparatus depicted in Figure 4. Figure 4. Brittleness test device.

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H-14 9.12.1. Cut the sample specimens 150-mm long from one continuous length. 9.12.2. Condition specimens at 4C 2C for a minimum of one hour. 9.12.3. Set the 9.5-kg top plate for a free fall of 500 mm to the uppermost surface of the specimen. 9.12.4. Locate the specimen on the bottom plate with the plane of the corrugated seams parallel to the plate. 9.12.5. Drop the upper plate and impact test the specimen within 30 seconds of removal from the conditioning environment. 9.12.6. Remove and inspect in accordance with the requirements of Section 7.16. 9.13. Pipe Dimensions: 9.13.1. Inside Diameter Measure the inside diameter of two sections of pipe with a tapered plug in accordance with ASTM D 2122. Alternatively, measure the inside diameter of two sections, with a suitable device accurate to 0.2 mm the mold partline and 90 degrees to it, and average the measurements. 9.13.2. Length Measure pipe with any suitable device accurate to 0.2%. Make all measurements on the pipe while it is stress free and at rest on a flat surface in a straight line. The length measurements may be taken at ambient temperature. 9.13.3. Perforations Measure dimensions of perforations on a straight specimen with no external forces applied. Make linear measurements with instruments accurate to 0.2 mm. 9.13.4. Inner Liner Measure the thickness of the inner liner with a digital micrometer or ultrasonic thickness gauge in accordance with ASTM D2122. 9.14. Couplings: 9.14.1. Joint Integrity This test is limited to only Type C and Type CP pipe supplied in coils. Assemble couplings to appropriate pipe in accordance with the manufacturer's recommendations. Use pipe samples at least 150 mm in length. Vertically suspend two pipe lengths connected by the joint couplings along their longitudinal axis. Then hang a tare mass from the lower end of the assembled pipe specimen for three minutes. Apply the test mass gently. Verify that the joint will support a mass along the pipe axis equal to 0.090 kg/mm of the nominal inside diameter, without separating. Test two coupling of each type. 9.14.2. Strength Assemble each coupling to the appropriate pipe in accordance with the manufacturer's recommendations. Use pipe samples at least 150 mm in length. Load the connected pipe and coupling between parallel plates at the rate of 12.5 mm/minute until the vertical inside diameter is reduced by at least 20% of the nominal diameter of the coupling. Inspect for damage while at the specified deflection and after load removal, and report the results of this inspection.

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H-15 9.14.3. Alignment Assure that the assembly or joint is correct and complete; if the pipe is bent, it should be hand-straightened prior to performing this test. Lay the assembly or joint on a flat surface and verify that it will accommodate straight-line flow. 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 or couplings 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 not more than 3.5 m, and fittings and couplings shall be clearly marked as follows: 11.1.1. Manufacturer's name or trademark, 11.1.2. Nominal size, 11.1.3. The specification designation AASHTO M252-Recycled, 11.1.4. The plant designation code, 11.1.5. The percentage recycled, and 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 8--A durable sticker is one that is substantial enough to remain in place and be legible through installation of the pipe. 12. QUALITY ASSURANCE 12.1. A manufacturer's certification that the product was manufactured, tested, and supplied in accordance with this specification and containing the percentage recycled shall be signed by a person authorized by the manufacturer.