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NR 440.647(2)(a)30. 30. “Low density polyethylene" or “LDPE" means a thermoplastic polymer or copolymer comprised of at least 50% ethylene by weight and having a density of 0.940 g/cm3 (58.7 lb/ft3) or less.
NR 440.647(2)(a)31. 31. “Low pressure process" means a production process for the manufacture of low density polyethylene in which a reaction pressure markedly below that used in a high pressure process is used. Reaction pressure of current low pressure processes typically go up to about 300 psig (2,070 kPa gauge).
NR 440.647(2)(a)32. 32. “Low viscosity poly(ethylene terephthalate)" means a poly(ethylene terephthalate) that has an intrinsic viscosity of less than 0.75 and is used in such applications as clothing, bottle and film production.
NR 440.647(2)(a)33. 33. “Material recovery section" means the equipment that recovers unreacted or by-product materials from any process section for return to the process line, off-site purification, treatment or sale. Equipment designed to separate unreacted or by-product material from the polymer product are to be included in this process section, provided at least some of the material is recovered for reuse in the process, off-site purification or treatment, or sale, at the time the process section becomes an affected facility. Otherwise such equipment are to be assigned to one of the other process sections, as appropriate. Equipment that treats recovered materials are to be included in this process section, but equipment that also treats raw materials are not to be included in this process section. The latter equipment are to be included in the raw materials preparation section. If equipment is used to return unreacted or by-product material directly to the same piece of process equipment from which it was emitted, then that equipment is considered part of the process section that contains the process equipment. If equipment is used to recover unreacted or by-product material from a process section and return it to another process section or a different piece of process equipment in the same process section or sends it off-site for purification, treatment or sale, then such equipment are considered part of a material recovery section. Equipment used for the on-site recovery of ethylene glycol from poly(ethylene terephthalate) plants, however, are not included in the material recovery section, but are covered under the standards applicable to the polymerization reaction section as described in sub. (3) (c) 1. b. 1) or 2. b. 1).
NR 440.647(2)(a)34. 34. “Operating day" means, for the purposes of these standards, any calendar day during which equipment used in the manufacture of polymer was operating for at least 8 hours or one labor shift, whichever is shorter. Only operating days shall be used in determining compliance with the standards specified in sub. (3) (c) 1. b. 2), 3), 2. b. 2) and 3). Any calendar day in which equipment is used for less than 8 hours or one labor shift, whichever is less, is not an “operating day" and may not be used as part of the rolling 14-day period for determining compliance with the standards specified in sub. (3) (c) 1. b. 2), 3), 2. b. 2) and 3).
NR 440.647(2)(a)35. 35. “Polyethylene" means a thermoplastic polymer or copolymer comprised of at least 50% ethylene by weight.
NR 440.647 Note Note: See low density polyethylene and high density polyethylene.
NR 440.647(2)(a)36. 36. “Poly(ethylene terephthalate)" or “PET" means a polymer or copolymer comprised of at least 50% bis-(2-hydroxyethyl)-terephthalate (BHET) by weight.
NR 440.647(2)(a)37. 37. “Poly(ethylene terephthalate) (PET) manufacture using dimethyl terephthalate" means the manufacturing of poly(ethylene terephthalate) based on the esterification of dimethyl terephthalate (DMT) with ethylene glycol to form the intermediate monomer bis-(2-hydroxyethyl)-terephthalate (BHET) that is subsequently polymerized to form PET.
NR 440.647(2)(a)38. 38. “Poly(ethylene terephthalate) (PET) manufacture using terephthalic acid" means the manufacturing of poly(ethylene terephthalate) based on the esterification reaction of terephthalic acid (TPA) with ethylene glycol to form the intermediate monomer bis-(2-hydroxyethyl)-terephthalate (BHET) that is subsequently polymerized to form PET.
NR 440.647(2)(a)39. 39. “Polymerization reaction section" means the equipment designed to cause monomers to react to form polymers, including equipment designed primarily to cause the formation of short polymer chains (oligomers or low polymers), but not including equipment designed to prepare raw materials for polymerization, for example, esterification vessels. For the purposes of these standards, the polymerization reaction section begins with the equipment used to transfer the materials from the raw materials preparation section and ends with the last vessel in which polymerization occurs. Equipment used for the on-site recovery of ethylene glycol from poly(ethylene terephthalate) plants, however, are included in this process section, rather than in the material recovery process section.
NR 440.647(2)(a)40. 40. “Polypropylene" or “PP" means a thermoplastic polymer or copolymer comprised of at least 50% propylene by weight.
NR 440.647(2)(a)41. 41. “Polystyrene" or “PS" means a thermoplastic polymer or copolymer comprised of at least 80% styrene or para-methylstyrene by weight.
NR 440.647(2)(a)42. 42. “Post-impregnation suspension process" means a manufacturing process in which polystyrene beads are first formed in a suspension process, washed, dried or otherwise finished and then added with a blowing agent to another reactor in which the beads and blowing agent are reacted to produce expandable polystyrene.
NR 440.647(2)(a)43. 43. “Process heater" means a device that transfers heat liberated by burning fuel to fluids contained in tubular coils, including all fluids except water that is heated to produce steam.
NR 440.647(2)(a)44. 44. “Process line" means a group of equipment assembled that can operate independently if supplied with sufficient raw materials to produce polypropylene, polyethylene, polystyrene (general purpose, crystal or expandable) or poly(ethylene terephthalate) or one of their copolymers. A process line consists of the equipment in the following process sections, to the extent that these process sections are present at a plant: raw materials preparation, polymerization reaction, product finishing, product storage and material recovery.
NR 440.647(2)(a)45. 45. “Process section" means the equipment designed to accomplish a general but well-defined task in polymer production. Process sections include raw materials preparation, polymerization reaction, material recovery, product finishing and product storage and may be dedicated to a single process line or common to more than one process line.
NR 440.647(2)(a)46. 46. “Process unit" means equipment assembled to perform any of the physical and chemical operations in the production of polypropylene, polyethylene, polystyrene (general purpose, crystal or expandable) or poly(ethylene terephthalate) or one of their copolymers. A process unit can operate independently if supplied with sufficient feed or raw materials and sufficient storage facilities for the product. Examples of process units are raw materials handling and monomer recovery.
NR 440.647(2)(a)47. 47. “Product finishing section" means the equipment that treats, shapes or modifies the polymer or resin to produce the finished end product of the particular facility, including equipment that prepares the product for product finishing. For the purposes of these standards, the product finishing section begins with the equipment used to transfer the polymerized product from the polymerization reaction section and ends with the last piece of equipment that modifies the characteristics of the polymer. Product finishing equipment may accomplish product separation, extruding and pelletizing, cooling and drying, blending, additives introduction, curing or annealing. Equipment used to separate unreacted or by-product material from the product are to be included in this process section, provided the material separated from the polymer product is not recovered at the time the process section becomes an affected facility. If the material is being recovered, then the separation equipment are to be included in the material recovery section. Product finishing does not include polymerization, the physical mixing of the pellets to obtain a homogenous mixture of the polymer except as provided in this subdivision or the shaping, such as fiber spinning, molding or fabricating, or modification, such as fiber stretching and crimping, of the finished end product. If physical mixing occurs in equipment located between product finishing equipment, that is, before all the chemical and physical characteristics have been `set` by virtue of having passed through the last piece of equipment in the product finishing section, then the equipment is to be included in this process section. Equipment used to physically mix the finished product that is located after the last piece of equipment in the product finishing section is part of the product storage section.
NR 440.647(2)(a)48. 48. “Product storage section" means the equipment that is designed to store the finished polymer or resin end product of the particular facility. For the purposes of these standards, the product storage section begins with the equipment used to transfer the finished product out of the product finishing section and ends with the containers used to store the final product. Any equipment used after the product finishing section to recover unreacted or by-product material are to be considered part of a material recovery section. Product storage does not include any intentional modification of the characteristics of any polymer or resin product, but does include equipment that provides a uniform mixture of product, provided the equipment is used after the last product finishing piece of equipment. This process section also does not include the shipment of a finished polymer or resin product to another facility for further finishing or fabrication.
NR 440.647(2)(a)49. 49. “Raw materials preparation section" means the equipment located at a polymer manufacturing plant designed to prepare raw materials, such as monomers and solvents, for polymerization. For the purposes of these standards, this process section begins with the equipment used to transfer raw materials from storage and recovered material from material recovery process sections, and ends with the last piece of equipment that prepares the material for polymerization. The raw materials preparation section may include equipment that accomplishes purification, drying or other treatment of raw materials or of raw and recovered materials together, activation of catalysts, and esterification including the formation of some short polymer chains (oligomers), but does not include equipment that is designed primarily to accomplish the formation of oligomers, the treatment of recovered materials alone or the storage of raw materials.
NR 440.647(2)(a)50. 50. “Recovery system" means an individual unit or series of material recovery units, such as absorbers, condensers and carbon adsorbers, used for recovering volatile organic compounds.
NR 440.647(2)(a)51. 51. “Total organic compounds" or “TOC" means those compounds measured according to the procedures specified in sub. (6).
NR 440.647(2)(a)52. 52. “Uncontrolled emission rate" means the emission rate of a vent stream that vents directly to the atmosphere and the emission rate of a vent stream to the atmosphere that would occur in the absence of any add-on control devices but after any material recovery devices that constitute part of the normal material recovery operations in a process line where potential emissions are recovered for recycle or resale.
NR 440.647(2)(a)53. 53. “Vent stream" means any gas stream released to the atmosphere directly from an emission source or indirectly either through another piece of process equipment or a material recovery device that constitutes part of the normal recovery operations in a polymer process line where potential emissions are recovered for recycle or resale, and any gas stream directed to an air pollution control device. The emissions released from an air pollution control device are not considered a vent stream unless, as noted in this subdivision, the control device is part of the normal material recovery operations in a polymer process line where potential emissions are recovered for recycle or resale.
NR 440.647(2)(a)54. 54. “Volatile organic compounds" or “VOC" means, for the purposes of these standards, any reactive organic compounds as defined in s. NR 440.02.
NR 440.647(3) (3)Standards: process emissions.
NR 440.647(3)(a)(a) Each owner or operator of a polypropylene, low density polyethylene or high density polyethylene process line containing a process section subject to the provisions of this section shall comply with the provisions in this subsection on and after the date on which the initial performance test required by s. NR 440.08 is completed, but not later than 60 days after achieving the maximum production rate at which the affected facility will be operated, or 180 days after initial startup, whichever comes first.
NR 440.647(3)(a)1. 1. 'Continuous emissions.' For each vent stream that emits continuous emissions from an affected facility as defined in sub. (1) (a) 1., the owner or operator shall use the procedures identified in subd. 1. b. and c. for determining which continuous emissions are to be controlled and which level of control listed in subd. 1. a. is to be met. The owner or operator shall use the procedures identified in subd. 1. b. and c. each time a process section is constructed, modified or reconstructed at the plant site.
NR 440.647(3)(a)1.a. a. Level of control. Continuous emission streams determined to be subject to control pursuant to the procedures identified in subd. 1. b. and c., as applicable, shall meet one of the control levels identified in subd. 1. a. 1) to 4). The procedures in subd. 1. b. and c. identify which level of control may be met. The level of control identified in subd. 1. a. 4) is limited to certain continuous emission streams, which are identified through the procedures in subd. 1. b. and c.
1) Reduce emissions of total organic compounds (minus methane and ethane) (TOC) by 98 weight percent, or to a concentration of 20 parts per million by volume (ppmv) on a dry basis, whichever is less stringent. The TOC is expressed as the sum of the actual compounds, not carbon equivalents. If an owner or operator elects to comply with the 20 ppmv standard, the concentration shall include a correction to 3% oxygen only when supplemental combustion air is used to combust the vent stream.
2) Combust the emissions in a boiler or process heater with a design heat input capacity of 150 million Btu/hr or greater by introducing the vent stream into the flame zone of the boiler or process heater. If a boiler or process heater of lesser design heat capacity may be used, it shall demonstrate compliance with subd. 1. a. 1).
3) Combust the emissions in a flare that meets the conditions specified in s. NR 440.18. If the flare is used to control both continuous and intermittent emissions, the flare shall meet the conditions specified in s. NR 440.18 at all times, that is, when controlling continuous emissions alone or when controlling both continuous and intermittent emissions.
4) Vent the emissions to a control device located on the plant site.
NR 440.647(3)(a)1.b. b. Uncontrolled continuous emissions. For each vent stream that emits continuous emissions from an affected facility as defined in sub. (1) (a) 1. and that is not controlled in an existing control device, the owner or operator shall use the procedures identified in Table 3 to identify those continuous emissions from each constructed, modified or reconstructed affected facility that are to be controlled. The owner shall include in the procedure all uncontrolled continuous vent streams from previously constructed, modified, or reconstructed affected facilities at the plant site each time a process section is constructed, modified or reconstructed at the plant site. In applying the procedures shown in Table 3, the stream characteristics may be either measured or calculated as specified in sub. (6) (d). For modified or reconstructed affected facilities, these stream characteristics are to be determined after a modification or reconstruction determination has been made by the department, but before any actual changes have been undertaken, and then again after the actual changes have been made. Figure 1 provides a summary overview of the control determination procedure described in Table 3. - See PDF for table PDF - See PDF for table PDF - See PDF for table PDF
a Individual streams excluded under sub. (1) (g) from the requirements of sub. (3) are to be excluded from all calculations in this table. This paragraph exempts all individual emission streams with individual uncontrolled annual emission rates of less than 1.6 Mg/yr and all individual emission streams with individual TOC concentrations of less than 0.10% TOC by weight.
b For the 0.10 to less than 5.5 weight percent range, the following equations are used: - See PDF for table PDF
where
a = (0.12 - weight percent TOC) 2.5
c = (0.3 - weight percent TOC) 2
d = (0.4 - weight percent TOC) 1.5
For the 5.5 to less than 20 weight percent range, the following equations are used: - See PDF for table PDF
where:
- See PDF for diagram PDFFigure 1.
Decision Making Process for Uncontrolled Continuous Emissions from Polypropylene and Polyethylene Affected Facilities
NR 440.647(3)(a)1.c. c. Controlled continuous emissions. For each vent stream that emits continuous emissions from an affected facility as defined in sub. (1) (a) 1. and that is controlled in an existing control device, each owner or operator shall determine whether the emissions entering the control device are greater than or equal to the calculated threshold emissions (CTE) level, which is to be calculated using the TOC concentration of the inlet vent stream and the equations in footnote b of Table 3. If the inlet stream's TOC concentration is equal to or greater than 20 weight percent, the calculated threshold emissions level is 18.2 Mg/yr (20.1 ton/yr). If multiple emission streams are vented to the control device, the individual streams are not to be separated into individual weight percent ranges for calculation purposes as would be done for uncontrolled emission streams. Emissions vented to an existing control device are required to be controlled as described in subd. 1. c. 1) and 2). Figure 2 illustrates the control determination procedure for controlled continuous emissions.
- See PDF for diagram PDFNOTE: There are no individual stream exemptions from emissions already controlled by existing control devices.
Figure 2.
Decision Making Process for Continuous Emissions
Already Controlled at Polypropylene and Polyethylene Affected Facilities.
1) If the annual emissions of the stream entering the control device are equal to or greater than the CTE levels, then compliance with one of the requirements identified in subd. 1. a. 1), 2) or 3) is required when the control device is reconstructed or replaced or has its operating conditions modified as a result of state or local regulations, including changes in the operating permit, including those instances where the control device is reconstructed, replaced or modified in its operation at the same time the existing process section is modified or reconstructed and becomes an affected facility. If the existing control device already complies with one of the requirements identified in subd. 1. a. 1), 2) or 3) no further control is required.
2) If the annual emissions of the stream entering the control device are less than the CTE level, then the requirements of subd. 1. a. 1), 2) or 3) are not applicable at that time. However, if the control device is replaced, reconstructed or modified at a later date, each owner or operator shall reevaluate the applicability of these standards. This is done by combining with the vent stream entering the control device any uncontrolled vent streams in the same weight percent range as the controlled vent stream and determining whether the annual emissions of the stream entering the control device plus the applicable uncontrolled vent streams are greater than or equal to the CTE level, which is based on the weighted TOC concentration of the controlled vent stream and the uncontrolled vent streams. If the annual emissions entering the control device, including the applicable uncontrolled vent streams, are greater than or equal to the CTE level, then compliance with one of the requirements identified in subd. 1. a. 1), 2) or 3) is required at that time for both the controlled and uncontrolled vent streams. If the annual emissions are less than the CTE level, compliance with these standards is again not required at such time. However, if the control device is again replaced, reconstructed or modified, each owner or operator shall repeat this determination procedure.
NR 440.647(3)(a)2. 2. 'Intermittent emissions.' The owner or operator shall control each vent stream that emits intermittent emissions from an affected facility as defined in sub. (1) (a) 1. by meeting one of the control requirements specified in subd. 2. a. and b. If a vent stream that emits intermittent emissions is controlled in an existing flare, incinerator, boiler or process heater, the requirements of this paragraph are waived until such time the control device is reconstructed or replaced or is modified in its operating conditions as a result of state or local regulation, including changes in the operating permit. This paragraph does not apply to emergency vent streams exempted by sub. (1) (h) and as defined in sub. (2).
NR 440.647(3)(a)2.a. a. Combust the emissions in a flare that is:
1) Designed for and operated with no visible emissions, except for periods not to exceed a total of 5 minutes during any 2 consecutive hours,
2) Operated with a flame present at all times, and
3) Designed to maintain a stable flame.
NR 440.647(3)(a)2.b. b. Combust the emissions in an incinerator, boiler or process heater. The emissions shall be introduced into the flame zone of a boiler or process heater.
NR 440.647(3)(b) (b) Each owner or operator of a polystyrene process line containing process sections subject to the provisions of this section shall comply with the provisions in this subsection on and after the date on which the initial performance test required by s. NR 440.08 is completed, but not later than 60 days after achieving the maximum production rate at which the affected facility will be operated, or 180 days after initial startup, whichever comes first. Each owner or operator of a polystyrene process line using a continuous process shall:
NR 440.647(3)(b)1. 1. Limit the continuous TOC emissions from the material recovery section by complying with one of the following:
NR 440.647(3)(b)1.a. a. Not allow continuous TOC emissions to be greater than 0.0036 kg TOC/Mg (0.0072 lb TOC/ton) product.
NR 440.647(3)(b)1.b. b. Not allow the outlet gas stream temperature from each final condenser in the material recovery section to exceed -25°C (-13°F). For purposes of this standard, temperature excursions above this limit may not be considered a violation when the excursions occur during periods of startup, shutdown or malfunction.
NR 440.647(3)(b)1.c. c. Comply with par. (a) 1. a. 1), 2) or 3)
NR 440.647(3)(b)2. 2. If continuous TOC emissions from the material recovery section are routed through an existing emergency vapor recovery system, then compliance with these standards is required when the emergency vapor recovery system undergoes modification, reconstruction or replacement. In such instances, compliance with these standards shall be achieved no later than 180 days after completion of the modification, reconstruction or replacement.
NR 440.647(3)(c) (c) Each owner or operator of a poly(ethylene terephthalate) process line containing process sections subject to the provisions of this section shall comply with the provisions in this subsection on and after the date on which the initial performance test required by s. NR 440.08 is completed, but not later than 60 days after achieving the maximum production rate at which the affected facility will be operated, or 180 days after initial startup, whichever comes first.
NR 440.647(3)(c)1. 1. Each owner or operator of a PET process line using a dimethyl terephthalate process shall:
NR 440.647(3)(c)1.a. a. Limit the continuous TOC emissions from the material recovery section, that is, methanol recovery, by complying with one of the following:
1) Not allow the continuous TOC emissions to be greater than 0.018 kg TOC/Mg (0.040 lb TOC/ton) product.
2) Not allow the outlet gas stream temperature from each final condenser in the material recovery section, that is, methanol recovery, to exceed + 3°C (+ 37°F). For purposes of this standard, temperature excursions above this limit will not be considered a violation when the excursions occur during periods of startup, shutdown or malfunction.
NR 440.647(3)(c)1.b. b. Limit the continuous TOC emissions and, if steam-jet ejectors are used to provide vacuum to the polymerization reactors, the ethylene glycol concentration from the polymerization reaction section by complying with the following appropriate standard. The ethylene glycol concentration limits specified in subd. 1. b. 2) and 3) shall be determined by the procedures specified in sub. (6) (j).
1) Not allow continuous TOC emissions from the polymerization reaction section, including emissions from any equipment used to further recover the ethylene glycol, but excluding those emissions from the cooling tower, to be greater than 0.020 kg TOC/Mg (0.044 lb TOC/ton) product.
2) If steam-jet ejectors are used as vacuum producers and a low viscosity product is being produced using single or multiple end finishers or a high viscosity product is being produced using a single end finisher, maintain the concentration of ethylene glycol in the liquid effluent exiting the vacuum system servicing the polymerization reaction section at or below 0.35% by weight, averaged on a daily basis over a rolling 14-day period of operating days.
3) If steam-jet ejectors are used as vacuum producers and a high viscosity product is being produced using multiple end finishers, maintain an ethylene glycol concentration in the cooling tower at or below 6.0% by weight, averaged on a daily basis over a rolling 14-day period of operating days.
NR 440.647(3)(c)2. 2. Each owner or operator of a PET process line using a terephthalic acid process shall:
NR 440.647(3)(c)2.a. a. Not allow the continuous TOC emissions from the esterification vessels in the raw materials preparation section to be greater than 0.040 kg TOC/Mg (0.088 lb TOC/ton) product.
NR 440.647(3)(c)2.b. b. Limit the continuous TOC emissions and, if steam-jet ejectors are used to provide vacuum to the polymerization reactors, the ethylene glycol concentration from the polymerization reaction section by complying with the following appropriate standard. The ethylene glycol concentration limits specified in subd. 2. b. 2) and 3) shall be determined by the procedures specified in sub. (6) (j).
1) Not allow continuous TOC emissions from the polymerization reaction section, including emissions from any equipment used to further recover the ethylene glycol, but excluding those emissions from the cooling tower, to be greater than 0.020 kg TOC/Mg (0.044 lb TOC/ton) product.
2) If steam-jet ejectors are used as vacuum producers and a low viscosity product is being produced using single or multiple end finishers or a high viscosity product is being produced using a single end finisher, maintain the concentration of ethylene glycol in the liquid effluent exiting the vacuum system servicing the polymerization reaction section at or below 0.35% by weight, averaged on a daily basis over a rolling 14-day period of operating days.
3) If steam-jet ejectors are used as vacuum producers and a high viscosity product is being produced using multiple end finishers, maintain an ethylene glycol concentration in the cooling tower at or below 6.0% by weight, averaged on a daily basis over a rolling 14-day period of operating days.
NR 440.647(3)(d) (d) Closed vent systems and control devices used to comply with this section shall be operated at all times when emissions may be vented to them.
NR 440.647(3)(e) (e) Vent systems that contain valves that could divert a vent stream from a control device shall have car-sealed opened all valves in the vent system from the emission source to the control device and car-sealed closed all valves in vent system that would lead the vent stream to the atmosphere, either directly or indirectly, bypassing the control device.
NR 440.647(4) (4)Standards: equipment leaks of VOC.
NR 440.647(4)(a)(a) Each owner or operator of an affected facility subject to the provisions of this section shall comply with the requirements specified in s. NR 440.62 (3) as soon as practicable, but no later than 180 days after initial startup, except that indications of liquids dripping from bleed ports in existing pumps in light liquid service are not considered to be a leak as defined in s. NR 440.62 (3) (b) 2. b. For purposes of this standard, a “bleed port" is a technologically-required feature of the pump whereby polymer fluid used to provide lubrication, cooling, or both, of the pump shaft exits the pump, thereby resulting in a visible leak of fluid. This exemption expires when the existing pump is replaced or reconstructed.
NR 440.647(4)(b) (b) An owner or operator may elect to comply with the requirements specified in s. NR 440.62 (4) (a) and (b).
NR 440.647(4)(c) (c) An owner or operator may apply to the administrator for a determination of equivalency for any means of emission limitation that achieves a reduction in emissions of VOC at least equivalent to the reduction in emissions of VOC achieved by the controls required in this section. In doing so, the owner or operator shall comply with requirements specified in 40 CFR 60.484, as in effect on July 1, 1994.
NR 440.647(4)(d) (d) Each owner or operator subject to the provisions of this section shall comply with the provisions specified in s. NR 440.62 (6) except an owner or operator may use the following provision in addition to s. NR 440.62 (6) (e). Equipment is in light liquid service if the percent evaporated is greater than 10% at 150°C (302°F) as determined by ASTM D86-96, incorporated by reference in s. NR 440.17 (2) (a) 7.
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Published under s. 35.93, Stats. Updated on the first day of each month. Entire code is always current. The Register date on each page is the date the chapter was last published.