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workers, building, architect

NORA Manufacturing Sector Strategic Goals

927ZGRH - Occupation Exposures Sampling Strategies Manual Update

Start Date: 10/1/2008
End Date: 9/30/2013

Principal Investigator (PI)
Name: Martha Waters
Phone: 513-841-4458
Organization: NIOSH
Sub-Unit: DART
Funded By: NIOSH

Primary Goal Addressed

Secondary Goal Addressed

Attributed to Manufacturing


Project Description

Short Summary

This project will develop occupational exposure assessment strategies to enable prevention of work-related illness and injury. Evaluation of workplace exposure-response relationships requires detailed knowledge of worker exposures to potentially hazardous agents. The statistically random nature of exposure fluctuations complicates accurate and precise determination of worker exposures. Guidance on effective (meets performance objectives) and efficient (the most information for the least use of resources) exposure assessment sampling strategies is needed by occupational health professionals, particularly in the private sector. This project will develop this guidance and directly addresses the NIOSH Exposure Assessment Program mission to provide leadership in the development and use of effective exposure assessment strategies and tools to prevent work-related illness and injury, and will be useful to all employment sectors. Products will be guidance documents and software tools.


Purpose: The purpose of this project is to develop occupational exposure sampling strategy guidance appropriate for the evaluation and control of a variety of occupational exposure agents and stressors. This project was initiated to address the needs of stakeholders from industry, governmental, and labor organizations by providing an update and expansion of the NIOSH Occupational Exposure Sampling Strategies Manual (OESSM, 1977). Stakeholder needs have been obtained through the formation of a initial project team with external members from various sectors (2007), a public workshop with presentations by invited experts and facilitated discussions (11/2007), meetings with several experts (2/2008), and presentations and discussion sessions at a professional conference (AIHCE 6/2008).

Methods: Due to the large scope of this initiative combined with the variety of strategies required to address different exposure assessment needs and the complexity of the associated statistical tools, an OESS guidance document comprised of individual monographs or chapters will be developed. Each monograph or chapter will address a specific topic and will also serve as a component of a comprehensive exposure assessment strategy framework. This approach will be loosely based on the model of the NIOSH Manual of Analytical Methods. Some chapters will serve as the basis of journal publications. This approach permits incremental release of products. For each section or topic, existing research will be reviewed, new methods will be developed as needed (e.g. sample size formulae for specific sampling designs), guidance will be written, the document will be reviewed by experts and revised, and the written products will be disseminated. Most work will be completed by NIOSH staff with some use of contract task-orders for document development and review. A project team with internal and external members will be formed to guide the project.

Objectives and time frame: The specific aims of the project are to:

1.A. Review the state-of-the-science with respect to existing occupational exposure sampling strategies and produce a bibliographic database. Q1 FY09

1.B. Develop criteria for a performance-based exposure assessment sampling strategy. Q3 FY09

1.C. Communicate findings to occupational health community. Q4 FY09

2.A. Develop framework for exposure assessment strategies. FY10

2.B. Develop criteria for sampling plan design. FY10

2.C. Communicate findings to occupational health community. FY10

3.A. Describe methods for evaluation of exposure distributions. FY11

3.B. Describe methods for exposure distribution parameter estimation. FY11

3.C. Describe methods for evaluating exposure variability. FY12

3.D. Communicate findings to occupational health community. FY12

4.A. Describe interpretation methods for occupational exposure limits. FY13

4.B. Describe methods for determining OEL exceedance probabilities. FY13

4.C. Describe methods for determination of sample sizes based on OESSM performance objective. FY13

4.D. Communicate findings to occupational health community. FY13

5.A. Provide a set of computer-based statistical tools for exposure data evaluation. FY13

5.B. Communicate findings to occupational health community. FY13


1. Stakeholders will be contacted to identify trainings presented based on the NIOSH occupational sampling strategy methods.

2. Stakeholders will be polled (through professional associations and /or non-governmental organizations) to determine whether occupational exposure sampling strategy methods developed by NIOSH have been adopted or incorporated into private sector health and safety programs.

Mission Relevance

Effective exposure assessment strategies are needed to prevent work-related illness and injury. Exposition of occupational health risks requires assessment of worker exposures to potentially hazardous agents for the evaluation of exposure-response relationships.

This project aims to develop occupational exposure sampling strategy guidance appropriate for the evaluation and control of a variety of occupational exposure agents. This objective encompasses exposure measurement and estimation, sampling design including statistical tools, analysis and interpretation of exposure distribution data, statistically-based decision tools, and a comprehensive framework for managing the larger exposure assessment process, from qualitative assessment of workplace exposure factors to exposure surveillance. Previous NIOSH guidance was issued in 1977 in the document titled NIOSH Occupational Exposure Sampling Strategies Manual (OESSM). This highly influential document has been referred to in the occupational hygiene literature as "the most cited and discussed publication in occupational hygiene"; however this legacy NIOSH guidance is incomplete and now outdated.

Exposure assessment is complicated by the phenomenon of exposure variability over time and between workers. To obtain the best possible exposure estimates, recent advances in exposure assessment science must inform the occupational exposure assessment strategy. Knowledge about issues relevant to statistically-based exposure sampling strategies has increased greatly. In particular, (i) evidence now shows that substantial temporal and spatial exposure variability characterizes many work environments, leading to the need for more sophisticated and comprehensive sampling strategies, (ii) improvements in personal exposure monitoring methods have made it easier to collect sufficient exposure data for good decision-making, (iii) true risks associated with occupational exposures have become increasingly more difficult to detect over time increasing the need for very refined exposure assessment strategies for health studies, (iv) new statistical methods have been developed for designing sampling plans and analyzing exposure data, and (v) sampling strategy efficiencies can be achieved through recognition of the comparative magnitudes of environmental and sampling/analytical variability.

This project will contribute to the agenda of the Manufacturing Sector Program (MNF) because the outputs and potential outcomes, particularly in the first two years of the project, will deal primarily with exposure assessment of chemicals in air. The chemical production industry is part of the MNF, and the majority of the volume of use of chemicals occurs in the MNF. This project will address the exposures related to the disease endpoints of Strategic Goals 5 and 6 of the Manufacturing Sector. This project will contribute directly to the mission of the NIOSH Exposure Assessment Program (EXAP) to provide leadership in the development and use of effective exposure assessment strategies and tools to prevent work-related illness and injury.

Specifically, the following goals are addressed:

09PPEXAIG1.1: Develop guidance documents and statistical approaches for sampling strategies to determine worker exposure.

09PPEXAAOG1.1.1: Completion of a review of literature to assess currently existing guidance.

09PPEXAAOG1.1.2: Production of at least one document advancing state-of-the-art for exposure sampling strategies.

09PPEXAAOG1.1.3: Production of new or improved statistical approaches to exposure assessment sampling, including treatment of special issues and circumstances.

09PPEXAIG1.2: Update the historical NIOSH guidelines for sampling strategies, analysis and interpretation of exposure data.

09PPEXAAOG1.2.1: Completion of a review of existing tools and guidelines. 09PPEXAAOG1.2.2: Completion of updated guidelines and tools to address NIOSH and stakeholder-identified needs for exposure assessment methodologies, techniques, sampling plans and approaches.