Abstract

This analysis uses previously developed labor standards, flowcharting (Visio), and spreadsheets (Excel) to provide a model for predicting the labor required to manage field protective masks for the United States Marine Corps. In addition, by adjusting the parameters of the model, we are able to determine where improvements have the most beneficial impact on the program.

Instructions for the Mask Labor Estimations Spreadsheet

This document provides the background for the analysis of mask labor, and how to use the associated spreadsheet. The model was developed using the inventory transaction and inventory balance tables in WMS as well as observations from the field, Each process was broken down to its most elemental steps and a labor level of effort was assigned to each step. Historical data allowed us to assign a percentage of probability to the paths that masks might take through the process.

The level of effort values associated with each labor process and the percentages associated with each path through the process were modeled into an Excel spreadsheet that corresponds to the flow diagram. This spreadsheet allows us to conduct "what if" analyses to see where improvements to the process will have the greatest impact.

There are four major areas of activity for the field protective mask:

  • Bulk mask receipt
  • Individual Mask Recovery
  • Mask Sanitization
  • Individual Mask Issue
These areas are interlinked. Some masks will be routed off the main stream of processing based on their condition. Other masks will join a process from other processes. For example, some of the bulk masks will be routed into the sanitization and rebuild process if they are found to be dirty or missing parts. Likewise, masks received from individual Marines will have to be moved to storage with masks that were received in bulk. The model is built on this flow and the probability that masks will follow a given path to the next process. Each process has associated with it a labor standard that is expressed in minutes on a per mask basis. The standard probabilities and labor standards were established based on historical data. Both the labor standard and path probability may be modified to analyze a specific situation.

AREAS OF ACTIVITY

SAMPLE SPREADSHEET ANALYSIS

Bright green cells are parameters that are frequently evaluated.

STD = Current Standard

  • For labor standards this will be the estimated labor required to perform the task expressed in minutes.
  • For percentages, this will be a fraction representing the probability that a mask will follow the “yes” path in the flow chart.

The sample spreadsheet above is set up with the following parameters to allow for ease of following the math:

  • Bulk masks received = 1,000
  • Individual masks issued = 100
  • Individual masks recovered = 100
  • Masks in condition code A = .667 (33.3% failure rate)
  • Masks that are dirty = .500 (50% are clean / 50% need cleaning)
  • Masks in SL3 complete status = .900 (10% need SL3 adjustments)
  • Masks requiring left hand conversions = .050.

The following is a definition of the process steps and the current standards applied to each one.

Bulk Mask Receipt

Mask Issue

Mask Sent to EAU

Mask Recovery

Sanitization

Note; If time does not permit air drying of masks, the masks will be hand dried. This process takes about 4 minutes per mask. No standard has been set as to the percentage of masks that require hand drying.