The Logan sub-module is a Windows implementation of the Dupont/AIHA Logan software package that statistically analyses sampling results. It captures the PELs and sampling data by Material Class and uses parametric and non-parametric analysis for lognormal and normal distributions. LOGAN® results can be viewed graphically saved.
When you do noise or air monitoring, it is not feasible to collect a sample for each employee every day. Data collection from a workplace can only measure a small percentage of the exposures that occur, since exposure varies over time. Therefore, if you rely only on data collection, there is a risk of employee overexposure at any given time. Use of the Logan (lognormal analysis) program holds the risk of employee overexposure to workplace hazards to 5%, by allowing you to predict an SEG’s exposure to chemical, noise, and other environmental hazards from statistical analysis of a limited number of samples. When exposure to a hazard is predictable, it is easier to take the appropriate actions to ensure acceptable protection for employees.
The Logan program:
allows you to maintain employee risk of overexposure at less than 5%
provides cumulative probability plots
gives the measure of fit to the distribution
suggests frequency of resampling
allows you to save data and run the program from files.
How Logan Determines the Parameters for the Risk Criteria
How Logan Calculates Cumulative Probability
How Logan Suggests Resample Frequencies
Collecting Samples and Assessing Results