Dosimetric Techniques—The processes addressed here utilize a variety of techniques for the dynamic presentation of the product to the radiation source. This may involve gravitational flow or simple pneumatic transport about or past the radiation source. In the case of fluidized beds, the product may be presented to the radiation source while supported in a gaseous or liquid stream moving at relatively high velocities. This document provides a guide to the dosimetric techniques suitable for these processes. Food Products—Food products may be treated with ionizing radiation, such as energetic electrons from accelerators or gamma rays from 60Co or 137Cs sources, or X-rays, for numerous purposes, including control of parasites and pathogenic microorganisms, insect disinfestation, growth and maturation inhibition, and shelf-life extension. Note 1—Food irradiation specifications usually include upper and lower limits of absorbed dose: a minimum to ensure the intended beneficial effect and a maximum to avoid product degradation. For a given application, one or both of these values may be prescribed by regulations that have been established on the basis of available scientific data. Therefore, it is necessary to determine the capability of an irradiation facility to process within these absorbed-dose limits prior to the irradiation of the food product. Once this capability is established, it may be necessary to monitor and record the dose range delivered to the product during each production run to verify compliance with the process specifications within a predetermined level of confidence. Randomized Flow—In a stream of randomized flow; i.e. turbulent instead of laminar, variations occur which lead to a dose distribution for the particles entrained in the stream. The “idealized” maximum and minimum doses possible can be calculated based upon knowledge of the applied dose rate, the product dwell time in the irradiation cell and the product or bed thickness. The experimentally determined maximum and minimum doses delivered to each particle, should not be confused with these idealized dose limits. Treatment range—The location of the product (or of the dosimeter) in the fluidized bed or stream will determine its absorbed dose during passage through the radiation field. The experimental dose measurements in the fluidized bed or stream will define the range of product dose. The desired effect imparted to the product by irradiation will then be based upon this range of product dose and not upon maximum or minimum dose. Note 2—In situations where a randomized mixing within the fluidized bed occurs with the intention that the particles or fluid elements pass through several radiation zones and accumulate a total dose with different dose rates, maximum and minimum dose values are difficult to determine and must be based on the results for the experimental dosimetry irradiated with the product . In the case of fluids, stirring after processing results only in effective treatment at a mean dose; no max and min dose measurement. For example, lethality curves will be determined as a function of this range of product treatment to the product in the fluidized bed or stream as determined by dosimetric techniques.1.1 This guide describes several dosimetry systems and methods suitable for the documentation of the irradiation of product transported as fluid or in a fluidized bed. 1.2 The sources of penetrating ionizing radiation included in this guide are electron beams, X-rays (bremsstrahlung) and gamma rays. 1.3 Absorbed doses from 10 to 100,000 gray are considered, including applications such as disinfestation, disinfection, bioburden reduction, sterilization, crosslinking and graft modification of products, particularly powders and aggregates. 1.4 This guide does not purport to address the safety concerns, if any, associated with the use of fluidized beds and streams incorporating sources of ionizing radiation. It is the responsibility of the user of this guide to establish appropriate safety and health practices and to determine compliance with regulatory limitations prior to use.

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This consumer safety specification deals with the requirements for the design and performance of toddler beds. It also contains requirements for labeling and instructional material. This consumer safety specification is intended to minimize incidents to children resulting from normal use and reasonably foreseeable misuse of toddler beds. It does not address incidents resulting from alteration or unreasonable misuse. Materials shall be tested and shall conform to requirements of small parts, paint and surface coating, scissoring, shearing, and pinching, protective components, openings, labeling, corner post extensions, mattress retention, mattress support system, mattress support system attachment to end structures, guardrails, end structures, partially bounded openings, and permanency of labels and warnings.1.1 This consumer safety specification covers requirements for the design and performance of toddler beds. It also contains requirements for labeling and instructional material.1.2 This consumer safety specification is intended to minimize incidents to children resulting from normal use and reasonably foreseeable misuse of toddler beds. It does not address incidents resulting from alteration or unreasonable misuse.1.3 For the purposes of this consumer safety specification, a toddler bed is a bed that is sized to accept a full-size crib mattress and is intended for use by a child not less than 15 months of age and who weighs no more than 50 lb (27.7 kg).1.4 No toddler bed produced after the approval date of this consumer safety specification shall indicate compliance with this specification, either by label or by other means, unless it conforms to all the requirements contained herein.1.5 This consumer safety specification includes the following sections: Section 1Referenced Documents Section 2Terminology Section 3Calibration and Standardization Section 4General Requirements Section 5Performance Requirement Section 6Test Methods Section 7Marking and Labeling Section 8Instructional Literature Section 9Keywords Section 101.6 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.7 The following safety hazards caveat pertains only to the test methods portion, Section 7, of this consumer safety 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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1 Scope and object This clause of the General Standard applies, except as follows: 1.1 Scope Addition: This Particular Standard specifies requirements for safety of ELECTRICALLY OPERATED HOSPITAL BEDS, hereinafter referred to as BED, as defined in 2.

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1.1 This consumer safety specification establishes minimum requirements for the design and performance of bunk beds. It also contains requirements for labeling and instructional material.1.2 This consumer safety specification is intended to minimize accidents to children resulting from normal use and reasonably foreseeable misuse or abuse of bunk beds. This consumer safety specification is written within the current state of the art of bunk bed technology and does not address bunk beds that are blatantly misused or are used in a careless manner that disregards warning statements and safety instructions provided with each bunk bed.1.3 For the purpose of this consumer safety specification, a bunk bed (hereinafter referred to as a bed) is defined as any structure that includes at least one sleeping surface in which the underside of any of its foundations is over 30 in. (762 mm) from the floor.1.4 This consumer safety specification does not address bunk beds for institutional use (for example, in prisons, military facilities, dormitories, and so forth).1.5 The values stated in inch-pound units, as well as any specified ISO/ANSI standard hardware, are to be regarded as the standard. The values given in parentheses are for information only.1.6 The following safety hazards caveat pertains only to the test methods portion, Section 5, 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Assumptions: 5.1.1 The control well discharges at a constant rate, Q.5.1.2 The control well is of infinitesimal diameter and fully penetrates the aquifer.5.1.3 The aquifer is homogeneous, isotropic, and areally extensive.NOTE 1: Slug and pumping tests implicitly assume a porous medium. Fractured rock and carbonate settings may not provide meaningful data and information.5.1.4 The aquifer remains saturated (that is, water level does not decline below the top of the aquifer).5.1.5 The aquifer is overlain or underlain, or both, everywhere by confining beds individually having uniform hydraulic conductivities, specific storages, and thicknesses. The confining beds are bounded on the distal sides by one of the cases shown in Fig. 1.5.1.6 Flow in the aquifer is two-dimensional and radial in the horizontal plane.5.2 The geometry of the well and aquifer system is shown in Fig. 1.5.3 Implications of Assumptions: 5.3.1 Paragraph 5.1.1 indicates that the discharge from the control well is at a constant rate. Paragraph 8.1 of Test Method D4050 discusses the variation from a strictly constant rate that is acceptable. A continuous trend in the change of the discharge rate could result in misinterpretation of the water-level change data unless taken into consideration.NOTE 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.5.3.2 The leaky confining bed problem considered by the modified Hantush method requires that the control well has an infinitesimal diameter and has no storage. Moench (6) generalized the field situation addressed by the modified Hantush (1) method to include the well bore storage in the pumped well. The mathematical approach that he used to obtain a solution for that more general problem results in a Laplace transform solution whose analytical inversion has not been developed and probably would be very complicated, if possible, to evaluate. Moench (6) used a numerical Laplace inversion algorithm to develop type curves for selected situations. The situations considered by Moench indicate that large well bore storage may mask effects of leakage derived from storage changes in the confining beds. The particular combinations of aquifer and confining bed properties and well radius that result in such masking is not explicitly given. However, Moench ((6), p. 1125) states “Thus observable effects of well bore storage are maximized, for a given well diameter, when aquifer transmissivity Kb and the storage coefficient Ssb are small.” Moench (p. 1129) notes that “...one way to reduce or effectively eliminate the masking effect of well bore storage is to isolate the aquifer of interest with hydraulic packers and repeat the pump test under pressurized conditions. Because well bore storage C will then be due to fluid compressibility rather than changing water levels in the well”...“the dimensionless well bore storage parameter may be reduced by 4 to 5 orders of magnitude.”5.3.3 The modified Hantush method assumes, for Cases 1 and 3 (see Fig. 1), that the heads in source layers on the distal side of confining beds remain constant. Neuman and Witherspoon (7) developed a solution for a case that could correspond to Hantush's Case 1 with K" = O  = S" except that they do not require the head in the unpumped aquifer to remain constant. For that case, they concluded that the drawdowns in the pumped aquifer would not be affected by the properties of the other, unpumped, aquifer when (Neuman and Witherspoon (7) p. 810) time satisfies:5.3.4 Implicit in the assumptions are the conditions that the flow in the confining beds is essentially vertical and in the aquifer is essentially horizontal. Hantush's (8) analysis of an aquifer bounded only by one leaky confining bed suggested that these assumptions are acceptably accurate whereverThat form of relation between aquifer and confining bed properties may also be a useful guide for the case of two leaky confining beds.1.1 This practice covers an analytical procedure for determining the transmissivity and storage coefficient of a confined aquifer taking into consideration the change in storage of water in overlying or underlying confining beds, or both. This practice is used to analyze water-level or head data collected from one or more observation wells or piezometers during the pumping of water from a control well at a constant rate. With appropriate changes in sign, this practice also can be used to analyze the effects of injecting water into a control well at a constant rate.1.2 This analytical procedure is used in conjunction with Test Method D4050.1.3 Limitations—The valid use of the modified Hantush method (1)2 is limited to the determination of hydraulic properties for aquifers in hydrogeologic settings with reasonable correspondence to the assumptions of the Hantush-Jacob method (Practice D6029/D6029M) with the exception that in this case the gain or loss of water in storage in the confining beds is taken into consideration (see 5.1). All possible combinations of impermeable beds and source beds (for example, beds in which the head remains uniform) are considered on the distal side of the leaky beds that confine the aquifer of interest (see Fig. 1).FIG. 1 Cross Sections Through Discharging Wells in Leaky Aquifers with Storage of Water in the Confining Beds, Illustrating Three Different Cases of Boundary Conditions (from Reed (2) )1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.4.1 The procedures used to specify how data are collected/recorded and calculated in the standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of these test methods to consider significant digits used in analysis methods for engineering data.1.5 The values stated in SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values for the two systems may result in nonconformance with the standard. Reporting of results in units other than SI shall not be regarded as nonconformance with this standard.1.6 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of the practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without the consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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