Document 0LjD95G2ZQomO9xGv4a8wYOjV

Sampling Rate Changes The 3M Organic Vapor Monitor #3500 Sampling Guide R-35SG (May, 1981) It is recommended that the Sampling Rates published in the new Sampling Guide (R-35SG-May, 1981) be used in calculating contaminant concentrations for sampling done with the 3M Organic Vapor Monitor #3500. However, results obtained by use of previous sampling rate data (Compound Guide R-35CGL-A, 1981) are within the + 25% OSHA performance requirement for all sampling methods. The new Sampling Guide (May, 1981) is a result of a 3M R&D program directed toward gathering validation data on the 3M Organic Vapor Monitor. The project was similar in scope to the NIOSH Standards Completion Project which established the performance criteria for sampling methods (basically charcoal tube validation data). In completing this program, and over the past three years, increasingly more sophisticated methods of developing and handling experimental data evolved. This included the development of different techniques of generating known challenge concentrations, as well as increasing the number of samples run to yield a better statistical treatment of the data. As a result of this effort the sampling rates found in the new Sampling Guide are more accurate and consistent within each chemical group. All sampling rates in the May 1981 Guide have an accuracy of at least . 5%. Frank W. Snowden ANOTHER STEP TOWARDS BETTER OCCUPATIONAL HEALTH AND SAFETY 'CC ^ v> R-TDBLH(30.75)R Occupati nal Health and Safety Products Divisi n/3M 230-B 3M Center St. Paul, Minnesota 55101 Litho in U.StA. 3M 115360