USP37使用分析天平称量（中英文）(2014-06-06 14:11:08)转载分类：食品药品WEIGHING ON AN ANALYTICAL BALANCE使用分析天平称量（本文件来自USP37-NF32，目前尚未实施，信息仅供参考）INTRODUCTION介绍Weighing is a frequent step in analytical procedures, and the balance is an essential piece of laboratory equipment. The general information described here applies directly to electronic balances used in analytical procedures. Although many portions of the chapter are applicable to all balances, some are applicable only to analytical balances. This chapter should not be considered all-inclusive, and other sources of information (e.g., the US National Institute for Science and Technology and balance manufacturers) may be useful and applicable when analysts perform a weighing operation or implement a weighing procedureiii.The information given in this chapter is applicable not only to balances used for materials that must be accurately weighed (seeBalances41) but also to balances used in all analytical procedures.称重在分析程序中是一个很频繁的操作，天平是化验室的基本设备。这里的一般信息适用于在分析过程中使用的电子天平。尽管本章节的一部分也适用于所有天平，一些仅适用于分析天平。本章不应作为包括所有的文件，一些其它来源的信息（例如，美国国家科学技术研究所和天平生产商）可能也很有用，适用于化验员进行称量操作，或实施称重程序。本章中给出的信息不仅适用于必须精密称定的物质（参见天平41），同时也适用于所有分析过程中使用的天平。QUALIFICATION确认Users should consultAnalytical Instrument Qualification1058, standard operating procedures, and recommendations from manufacturers when they devise qualification plans.用户在设计其确认计划时，应参考分析仪器确认1058，标准操作规程，和生产商的推荐。Installation安装The balances performance depends on the conditions of the facility where it is installed. Analysts should consult information provided by the manufacturer before they install a balance.天平的性能取决于其安装所处的环境。在安装天平前，化验员应参考供应商给出的信息。Support surface:The balance should be installed on a solid, level, nonmagnetic surface that minimizes the transmission of vibration (e.g., a floor-mounted, granite weigh bench). If a metallic support surface is used, the surface should be grounded in order to prevent the buildup of static electricity.支持台面：天平应安装在坚固、水平、无磁场的平面，尽量减少震动传递（例如，安装在地板，花岗岩称重台）。如果采用了金属的支持台面，表面应接地，以避免静电聚积。Location:If possible, the balance should be located in a room that is temperature and humidity controlled. The location should have a clean, consistent electrical power supply. The location should be free of drafts and should not be near ovens, furnaces, air conditioner ducts, or cooling fans from equipment or computers.位置：如果可能，天平应安装在一个温湿度可控的房间。位置应清洁，具有持续的电力供应。位置应不会产生波动，不靠近烘箱、马弗炉、空调送回风罩，或设备、空调的冷却风扇。The balance should be positioned away from outside windows so that direct sunlight does not strike the balance. The balance should not be installed near sources of electromagnetic radiation such as radiofrequency generators, electric motors, or hand-held communication devices (including cordless telephones, cellular telephones, and walkie-talkies). The balance should not be located near magnetic fields induced by laboratory instrumentation or other equipment.天平位置应远离窗户，以避免直接阳光照射。天平安装不应靠近电磁辐射源，如无线频率发向射源，电子马达，或手动通话设施（包括无绳电话、手机、手提无线电话机）。天平不应安装在化验室设备或其它设备产生的磁场区域附近。The performance of the balance should be assessed following installation and before use in order to demonstrate adequate performance. In some situations, it may not be possible to position the balance in an optimum environment. Examples of potential facility issues include the following:天平的性能在安装后使用前应进行评估，以证明其性能符合要求。在某些情况下，可能无法将天平安装在一个理想的环境。潜在的设施问题包括以下：1. Air currents sometimes are present in the laboratory.化验室中有时会有气流2. Temperatures in the laboratory vary excessively (check the manufacturers literature about temperature sensitivity).化验室温度有时会快速波动（检查供应商关于温度敏感性的说明）3. Humidity is either very low or very high. Either condition may increase the rate at which the sample weight varies because of pickup or loss of water. Low humidity increases the buildup of static electricity.湿度可能会很低或很高。由于失水或吸水，太高或太低都会影响样品重量变动的速度。低湿度会增加静电积聚。4. Adjacent operations are causing vibration.邻近操作产生震动5. Corrosive materials are used nearby or are routinely weighed.附近使用腐蚀性材料，或常规称量腐蚀性物料6. The balance is located within a fume hood because it is used to weigh corrosive or hazardous materials.由于天平用于称量腐蚀性或危险性物料，因此安装在排烟罩内7. The balance is adjacent to equipment that produces a magnetic field (e.g., a magnetic stirrer).天平邻近产生磁场的设备（例如，电磁搅拌器）8. Direct sunlight strikes the balance.天平有直接太阳光照In situations when the balance is located near equipment or systems that induce vibration, drafts, electromagnetic radiation, magnetic fields, or changes in temperature or humidity, the assessment should be conducted with those systems operating in order to duplicate a worst-case scenario.如果天平位置接近产生震动、摆动、电磁辐射、磁场或温湿度变化的设备，则需要对这些系统在操作状态下进行评估，以重复最差情况环境。Operational Qualification运行确认An operational qualification should be performed either by the user or by a qualified third-party vendor after the equipment has been installed.在天平安装后，应由用户或第三方供应商进行运行确认。As a minimum, the power should be turned on and the balance should b