金币
UID11527
帖子
主题
积分1835
注册时间2011-12-29
最后登录1970-1-1
听众
性别保密
|
发表于 2014-12-10 13:11:59
|
显示全部楼层
你看看这个1. 《无菌药品》分册(14.3.1)
1.1. 限度确立方法:
1.1.1. 可以根据历史数据,结合不同洁净区域的标准制订。
 如采用数理统计(正态分布法)的方法,一般可以将平均值加上2倍的标准差作为警戒限度,加上3倍的标准差作为纠偏限度。
 其它模型基于负二项分布,泊松,韦伯,或基于其它指数分布模型也是可以的。
 对于不同的数据选择不同的模型来确定其限度值。典型的是在环境控制区域,污染并不属于正态分布。
 环境监测数据可进行评估,以确定合适的方法来设定限度值。对新厂房而言,可根据以前的类似设施或工艺制定这些限度,并且要进行一段时间的环境监测,根据监测数据来评价事先确立的警戒限度是否合适,并做出相应调整。
1.1.2. 纠偏限度不得高于相应洁净级别下的参照性限度标准(GMP、国标等规定的环境控制标准)。
1.2. 限度回顾:
限度设定后,应定期回顾评价,如每个季度或年度。如果历史性数据表明环境有所 改善,则限度也应作出相应调整以反映出实际的环境状况。
2. PDA TR No. 13:Fundamentals of an Environmental Monitoring Program
2.1. Cutoff Value Approach 截断值法(阈值法)
All the test data for a particular site, or group of similar sites, are arranged in a histogram and the alert and action levels are set at values whose monitoring results are respectively 1% and 5% higher than the level selected. Other percentiles may be used in establishing levels. A variation is to take the last 100 monitoring results and use the 95th and 99th percentile values as the alert and action levels
所有测试数据或者网站上的一组数据,以直方图形式排列出,警戒限和行动限分别设置高于监测结果水平的1%和5%。其它百分数可用于建立监测结果水平。例如,用最后100个监测结果的第95和第99百分位值作为警戒和行动水平。
2.2. Normal Distribution Approach 正态分布法
This approach is best used for high counts only(a Poisson distribution is used for low counts).The mean and standard deviation of the data are calculated and the alert and action levels are set at the mean plus two and three times the standard deviation, respectively.
这个方法只适合高计数(播送分布用于低计数)。计算数据的平均值和标准差,警戒限和行动限分别设置为平均值加2倍和3倍标准差。
2.3. Non-parametric Tolerance limits Approach 非参数公差限值法
In this approach , alert and action limits are set using non-parametric(distribution free)methods.This is valuable for environmental monitoring data that typically is not normally distributed, i. e,
exhibit high levels of skewness towards zero counts. For the alert limit, the tolerance limit was set at a level of γ=0.95 and P=0.95. The action limit resulted from a tolerance limit set at γ=0.95 and P=0.99. These limits allow us to assert with confidence at least 95% that 100(P) or 99% of a
population for the respective data.
这个方法中,警戒限和行动限设置使用非参数法(自由分布)。此方法适用于非正常分布的环境监测数据,例如高水平的数据偏向零。对于警戒限,设置为公差范围γ=0.95、P=0.95。行动限设置为公差范围γ=0.95、P=0.99。
2.4. Other 其它
Other models based on negative binomial, Poisson, Weibull, or exponential distributions are possible. It may be appropriate to determine the model that best fits the data and use that model to set the levels. Typically, contamination in strictly controlled environments does not fall within a normal distribution. Environmental monitoring data may be evaluated to determine the suitability of the approaches to level setting.
其它方法基于负二项分布,泊松,韦伯,或基于其它指数分布模型也是可以的。确定最适合数据设定水平的方法。严格控制环境中污染不属于正态分布。环境监测数据可用于评价和确定监测水平制定方法的合理性。
|
|