Skip Navigation



Annals of Occupational Hygiene Advance Access published online on July 7, 2004

Annals of Occupational Hygiene, doi:10.1093/annhyg/meh032
Copyright © 2004 by the British Occupational Hygiene Society.
This Article
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
48/5/491    most recent
meh032v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Flynn, M. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Flynn, M. R.
Social Bookmarking
 Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Received November 22, 2003
Accepted January 20, 2004

Article

A Stochastic Differential Equation for Exposure Yields a Beta Distribution

Michael R. Flynn 1*

1 CB7431 Rosenau Hall, Department of Environmental Sciences and Engineering, School of Public Health, University of North Carolina, Chapel Hill, NC 27566-7431, USA

* To whom correspondence should be addressed. E-mail: mike{at}flynn.edu.


   Abstract

This paper presents a stochastic differential equation for exposure based on a modified version of the standard dilution ventilation equation. An equilibrium solution is obtained with the assumption that variability in the rate of change of concentration is proportional to the product of concentration and one minus concentration. Appropriate definitions for concentration are used to ensure a physically consistent model. The probability distribution for exposure that results is the standard beta distribution. This model is supported by several exposure data sets, which fit the beta distribution well. Issues regarding parameter estimation for the beta distribution, and application of the model are presented. Recommendations are made for simultaneously collecting contaminant generation rate information, ventilation rates, and time dependent breathing-zone tracer concentrations, in addition to the exposure data.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
ANN OCCUP HYGHome page
M. R. FLYNN
The 4-Parameter Lognormal (SB) Model of Human Exposure
Ann. Hyg., October 1, 2004; 48(7): 617 - 622.
[Abstract] [Full Text] [PDF]



Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.