What percentage must blind analysis fall within to maintain accuracy?

The percentage range that blind analysis must fall within to maintain accuracy is 80-120%. This range is established to ensure that results reflect a minimally acceptable margin of error, allowing for variations that might occur during testing or measurement processes.

In practice, this means that if a result from an analysis shows a concentration or measurement, it should be within 80% to 120% of what is expected or known for it to be deemed accurate. This acceptable range acknowledges that testing methods can have slight discrepancies but still provides a framework for determining reliability in results.

While other ranges may seem plausible, they do not align with the standards set forth in lead risk assessment practices. For instance, a range of 50-70% would be too broad and could permit results that are not sufficiently close to expected values, while options such as 90-100% or 100-150% either restrict acceptable error margins too tightly or broaden them excessively. Hence, the 80-120% range is the most reasonable for ensuring the accuracy of blind analysis in this context.