ASTM D6494-22 PDF

Overview

ASTM D6494-22, titled Standard Test Method for Determination of Asphalt Fume Particulate Matter in Workplace Atmospheres as Benzene Soluble Fraction, provides a rigorously defined approach for measuring the concentration of asphalt fume particulate matter in the air at worksites. This method focuses on isolating the benzene soluble fraction (BSF) from airborne particulates, ensuring reliable exposure assessments for workers in environments where asphalt materials are present. Employing a polytetrafluoroethylene (PTFE) filter-based sampling process, the standard supports both area and personal air monitoring. This method aligns with internationally recognized occupational exposure limits, including those established by ACGIH, and builds upon former NIOSH and OSHA methods to improve reproducibility and lower background contamination.

Key Topics

• Air Monitoring and Exposure Assessment: Establishes a robust means for determining worker exposure to hazardous asphalt fumes in occupational environments such as road construction and roofing.
• Sampling Methodology: Specifications for PTFE filter cassettes (2μm pore size), sampling pumps capable of 0.5 to 2.0 L/min flow rates, and chain-of-custody requirements for sample integrity.
• Benzene Soluble Fraction (BSF): Defines the gravimetric procedure for extracting and measuring only the benzene soluble fraction from collected particulate matter, a key indicator linked to occupational health guidelines.
• Time-Weighted Average (TWA) and Short-Term Exposure Limit (STEL): Method generates time-weighted average data, facilitating regulatory compliance over both short- and long-duration exposures in the concentration range from 0.2 to 2.0 mg/m³.
• Precision and Bias: Details on repeatability, accuracy, and quality assurance parameters to ensure defensible monitoring results.
• Safety Considerations: Addresses the proper handling of hazardous reagents like benzene and dichloromethane and stresses the importance of adhering to laboratory safety protocols.

Applications

• Workplace Air Quality Monitoring: Essential for industrial hygienists and safety professionals tasked with monitoring and controlling occupational exposure to asphalt fumes in sectors such as highway construction, paving, and roofing.
• Regulatory Compliance: Supports efforts to meet occupational exposure limits (e.g., ACGIH TLVs and BEIs) and informs hazard assessments required by OSHA and other regulatory agencies.
• Health and Safety Programs: Provides critical data for evaluating the effectiveness of engineering controls, personal protective equipment, and process modifications.
• Laboratory Analysis: Outlines procedures suitable for use in accredited laboratories, compatible with high flow rate personal monitoring equipment, and consistent with ISO/IEC 17025 requirements for testing and calibration laboratories.
• Research and Development: Offers baseline methodology for scientific studies investigating the toxicity, exposure routes, or mitigation of asphalt fumes in various workplace scenarios.

Related Standards

For comprehensive workplace air sampling and analysis, users of ASTM D6494-22 should consider the following related standards:

• ASTM D1356 - Terminology Relating to Sampling and Analysis of Atmospheres
• ASTM D1357 - Practice for Planning the Sampling of the Ambient Atmosphere
• ASTM D4840 - Guide for Sample Chain-of-Custody Procedures
• ASTM D5337 - Practice for Flow Rate Adjustment of Personal Sampling Pumps
• ASTM D6062 - Guide for Personal Samplers of Health-Related Aerosol Fractions
• ASTM D8358 - Guide for Assessing and Including Wall Deposits in Airborne Particulate Matter Analysis
• OSHA Method 58 - Coal Tar Pitch Volatiles
• NIOSH Method 5042 - Benzene Soluble Fraction and Total Particulate (Asphalt Fume)
• ISO/IEC 17025 - General Requirements for the Competence of Testing and Calibration Laboratories

Employing ASTM D6494-22 helps ensure that air quality measurements for asphalt fume particulate matter in workplace atmospheres are scientifically sound, reproducible, and defensible, thereby protecting worker health and supporting regulatory compliance initiatives.