1、Designation: C 1661 07Standard Guide forViewing Systems for Remotely Operated Facilities1This standard is issued under the fixed designation C 1661; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A numbe
2、r in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 Intent:1.1.1 This guide establishes the minimum requirements forviewing systems for remotely operated facilities, including hotcells (shiel
3、ded cells), used for the processing and handling ofnuclear and radioactive materials. The intent of this guide is toaid in the design, selection, installation, modification, fabrica-tion, and quality assurance of remote viewing systems tomaximize their usefulness and to minimize equipment failures.1
4、.1.2 It is intended that this guide record the principles andcaveats that experience has shown to be essential to the design,fabrication, installation, maintenance, repair, replacement, and,decontamination and decommissioning of remote viewingequipment capable of meeting the stringent demands of ope
5、r-ating, dependably and safely, in a hot cell environment whereoperator visibility is limited due to the radiation exposurehazards.1.1.3 This guide is intended to apply to methods of remoteviewing for nuclear applications but may be applicable to anyenvironment where remote operational viewing is de
6、sirable.1.2 Applicability:1.2.1 This guide applies to, but is not limited to, radiationhardened and non-radiation hardened cameras (black- and-white and color), lenses, camera housings and positioners,periscopes, through wall/roof viewing, remotely deployablecameras, crane/robot mounted cameras, end
7、oscope cameras,borescopes, video probes, flexible probes, mirrors, lighting,fiber lighting, and support equipment.1.2.2 This guide is intended to be applicable to equipmentused under one or more of the following conditions:1.2.2.1 The remote operation facility that contains a signifi-cant radiation
8、hazard to man or the environment.1.2.2.2 The facility equipment can neither be accesseddirectly for purposes of operation or maintenance, nor can theequipment be viewed directly, for example, without shieldingviewing windows, periscopes, or a video monitoring system.1.2.2.3 The facility can be viewe
9、d directly but portions ofthe views are restricted (for example, the back or underside ofobjects) or where higher magnification or specialized viewingis beneficial.1.2.3 The remote viewing equipment may be intended foreither long-term application (commonly, in excess of severalyears) or for short-te
10、rm usage (for example, troubleshooting).Both types of applications are addressed in sections that follow.1.2.4 This guide is not intended to cover the detailed designand application of remote handling connectors for services (forexample, electrical, instrumentation, video, etc.).1.2.5 The system of
11、units employed in this guide is themetric unit, also known as SI Units, which are commonly usedfor International Systems, and defined by ASTM/IEEE SI-10,Standard for Use of International System of Units. Some videoparameters use traditional units that are not consistent with SIUnits but are used wid
12、ely across the industry. For example,video image format is referred to in “inch” units. (See Table 1.)1.2.6 Lens and lens element measurements are always inmillimeter (mm) units, even where SI Units are not in commonusage, as an industry practice. Other SI Units (for example,cm) are rarely used for
13、lenses or lens elements.1.2.7 Unless otherwise mentioned in this guide radiationexposure refers to gamma energy level in terms of60Coexposure, and radiation per hour or rad/h refers to instanta-neous rate and not cumulative values.1.3 User Caveats:1.3.1 This guide does not cover radiation shielding
14、windowsused for hot cell viewing. They are covered separately underGuide C 1572.1.3.2 This guide is not a substitute for applied engineeringskills, proven practices and experience. Its purpose is toprovide guidance.1.3.3 The guidance set forth in this guide relating to designof equipment is intended
15、 only to inform designers and engi-neers of these features, conditions, and procedures that havebeen found necessary or highly desirable to the design,1This guide is under the jurisdiction of ASTM Committee C26 on Nuclear FuelCycle and is the direct responsibility of Subcommittee C26.14 on Remote Sy
16、stems.Current edition approved Feb. 1, 2007. Published April 2007.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.selection, operation and maintenance of reliable remote view-ing equipment for the subject service conditions.1.3.4 The
17、 guidance set forth in this guide results fromoperational experience of conditions, practices, features, lackof features, or lessons learned that were found to be sources ofoperating or maintenance problems, or causes of failure.1.3.5 This guide does not supersede federal or state regula-tions, or c
18、odes applicable to equipment under any conditions.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of r
19、egulatory limitations prior to use.2. Referenced Documents2.1 Industry and National Consensus StandardsNationally recognized industry and consensus standards appli-cable in whole or in part to the design, fabrication, qualityassurance, inspection, testing, and installation of equipment arereferenced
20、 throughout this guide and include, but are notlimited to, the following:2.2 ASTM Standards:2C 1217 Guide for Design of Equipment for ProcessingNuclear and Radioactive MaterialsC 1533 Guide for General Design Considerations for HotCell EquipmentC 1554 Guide for Materials Handling Equipment for HotCe
21、llsC 1572 Guide for Dry Lead Glass and Oil-Filled Lead GlassRadiation Shielding Window Components for RemotelyOperated FacilitiesE 170 Terminology Relating to Radiation Measurementsand DosimetryASTM/IEEE SI 10 Standard for Use of the InternationalSystem of Units2.3 Other Standards:ANS 8.1 Nuclear Cr
22、iticality Safety in Operations withFissile Materials Outside Reactors3ANS Design Guides for Radioactive Material HandlingFacilities however,this should not be at the expense of overly complex wiringsince this can be even more difficult to repair.6.2.2 Materials of construction of remote viewing equi
23、p-ment on the side should be radiation resistant, compatible withthe hot cell environment, easily decontaminated, and compat-ible with other materials with which they are in contact, to theextent possible and where economically feasible.6.2.3 Wiring between the remote and accessible portions ofany v
24、iewing system should be simplified, in number of wiresand types of wires, as much as possible and wiring-sensitiveC1661076signals (for example, low level or noise sensitive signals)should be avoided if possible. The simplicity and robustness ofthe wiring, to and from a remote system, can be a majord
25、eterminate of the success of an installation. Complex wiring,signals affected by electrical interference, and connectors withlarge numbers of connection pins, can significantly reduce theusefulness or survival of an installation, and remote mainte-nance. The remote wiring should be suitable for the
26、life of thefacility and, if possible, be remotely replaceable after a facilityis in radioactive operation, since the inability to repair non-functional wiring would terminate a remote viewing system.See NFPA 70, 47CFR.6.2.4 The inevitable remote replacement or removal ofremote viewing components sho
27、uld be carefully consideredduring the design phase. The complexity and fragility ofremote viewing systems as compared to more robust items (forexample, pumps, motors, etc.) increases the likelihood offailure in any design. Replacement of systems should incorpo-rate mechanical interfaces, and electri
28、cal connectors compat-ible with the manipulation means in a hot cell.6.2.5 During the facility design phase, the potential need forremote viewing equipment should be carefully considered, sothat provisions can be made for its deployment. Such provi-sions might include mechanical mounting, wall tubes
29、, electri-cal feed-throughs, brackets, etc. in a potential location for aremote viewing apparatus. These provisions should have aminimal impact on the initial construction, and significantlyreduce the difficulty of a remote viewing deployment at a laterdate.6.2.6 Multiple remote viewing systems shou
30、ld be standard-ized as much as possible to minimize expense and improvemaintenance. The maintenance of remote viewing systemsoften requires a pre-staged camera mount with services forconnectors, typically assembled and tested in a mock-upfacility, to allow rapid maintenance and to minimize thepotent
31、ial for personnel exposure. Standardized designs allow aminimum number of pre-staged mounts to be required andmaximizes the speed of repair. The mock-up facility usuallyprovides for a test version of the mechanical and electricalinterfaces that are located in the radiological environmentwhere the re
32、mote system can be tested. This assures theirproper fit, interfacing, operation, and maintenance prior to theiractual installation in a hot cell or similar environment.7. Materials of Construction7.1 Material of Construction in Hazardous Environments:7.1.1 Remote viewing systems materials of constru
33、ctionshould be resistant to the expected chemical and mechanicalenvironment of a hot cell while maintaining radiation hardnessappropriate to the application.7.1.2 The chemical environment of a hot cell is often hostileto exposed components or materials; this includes the usage ofaggressive chemicals
34、 for decontamination purposes. This prob-lem can be addressed by enclosing a viewing system in sealed,and sometimes pressurized, housings with sealed viewingwindows. Typically, glass or fused silica quartz viewingwindows can be used with the latter being much more resistantto high radiation. Wiring
35、should be either completely enclosedwithin housings (note: various methods below) or protected bychemical resistant jackets.7.1.3 The construction materials used should be resistant toa discharge of the in-hot cell fire suppression system, if present.7.1.4 The radiation effects on viewing systems in
36、volve boththe lifetime dosage and the maximum dose rate. Radiation-induced noise at high dose rates can severely degrade the videoimage, even though the video system may not suffer significantdamage over a short period exposure.7.1.5 Careful consideration should be given to the expectedtotal accumul
37、ated radiation dose and maximum dose rates forthe specific remote operations to which the viewing systemswill be exposed. Often the radiation requirements are overspecified due to limited information or assumptions. This canresult in considerable increases of system costs or complexitybeyond what is
38、 necessary.7.1.6 The radiation resistance of materials is of particularconcern in remote viewing systems, due to the wide variety ofmaterials required (for example, electronics, lenses, windows,wiring, motors, limit switches, insulators).All critical materials(that is, those that would cause a syste
39、m to fail) should beevaluated to determine their suitability for the radiation hard-ness requirements in a hot cell. If possible, investigate whetherirradiation test certificates or reports are available to provideconfidence that equipment will survive the environment in- hotcell, or establish a rad
40、iation resistance test program formaterials used.7.1.7 High total dose requirements can be accommodatedby designing the remotely deployed portion of a viewingsystem for simplified replacement. The tradeoffs of designingfor higher radiation performance versus designing for morefrequent replacement sh
41、ould be evaluated for each system.7.1.8 The energy level of the expected radiation should becarefully considered in all materials and shielding evaluations.The amount of shielding that is effective against high energyradiation (for example,60Co) is dramatically different thanlower energy radiation (
42、for example,137Cs) and this should betaken into account.7.1.9 The type of ionizing radiation expected (that is, alpha,beta, gamma, neutron) can also have an unexpected effect onmaterials of construction. It is well known that the largerradiation particles (alpha or beta) can be easily stopped by thi
43、nmetallic or non-metallic shielding materials; however, it isoften not appreciated that non-metallic shielding materials canbe severely damaged in the process. Plastic, elastomeric,rubber, or similar materials can be severely damaged by directexposure to alpha and beta radiation.8. Hazard Sources an
44、d Failure Modes8.1 Remote Viewing Components:8.1.1 Remote viewing systems should function acceptablyin the presence of a variety of hazards. The best estimates ofthe nature and severity of these hazards should be determinedbefore remote systems are designed and fabricated.8.1.2 Radiation hazards can
45、 include x-rays, alpha, beta,gamma, and infrequently neutrons. The materials of construc-tion and decontamination techniques should be compatiblewith the expected types and levels. When neutrons are presentthe potential for material activation should be evaluated.C16610778.1.3 Chemical environments
46、are often present in hot cellfacilities since they are often used for experiments, specializedprocessing, or decontamination of equipment. The compatibil-ity of the hot cell chemical environment with the type ofviewing system equipment to be used should be evaluatedaccordingly.8.1.4 High temperature
47、s and high humidity can be presentin some facilities and can have a severe effect on remoteviewing systems where electronics are located in the hot cell.The combined effects of temperature and radiation on remotesystems, when they occur simultaneously, can significantlyshorten the life of equipment.
48、8.1.5 High levels of vibration and shock can occur in hotcell facilities, since powerful equipment (that is, motors,pumps, cranes, or manipulators) can be in close proximity in aconcrete structure. Consideration should be given to the shockloading on a viewing system, during installation, maintenanc
49、eactivities, and during routine operation. Viewing systemsinstalled on moving or vibrating equipment (for example,on-crane mounted remote cameras) must accommodate longterm and possible severe shock loading. These factors shouldbe evaluated to determine their effect on remote viewingequipment or steps should be taken to minimize their effects.8.1.6 High levels of electromagnetic interference, or elec-trical noise, may exist when high-power equipment is operatedand may degrade the performance of the remote viewingsystem. Image sensor tubes, still commonly used in mostradiation hardened c
