Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
D6306-17 – Standard Test Method Technical Guide
📐 Scope and Application
ASTM D6306-17 (Reapproved 2024) provides a standardized framework for deploying diffusive samplers to measure gaseous pollutants in indoor air. According to Section 1.3, a diffusive sampler is defined as any device that samples according to Fick’s first law of diffusion without the aid of electrical or mechanical power. This guide specifically targets non-industrial environments, including residences, public buildings, and offices (Section 1.3), to measure time-weighted average (TWA) exposure concentrations for occupants (Section 1.2). All measurements are standardized in SI units (Section 1.5).
🎯 Core Objective — The primary purpose of this guide is to ensure uniformity of sampling within a variety of indoor environments and to facilitate the comparison of results between different studies and locations (Section 1.4).
⚙️ Sampling Mechanism and Key Principles
Diffusive samplers operate by allowing gaseous contaminants in a molecular state to diffuse through a defined geometric structure into an adsorbing region containing sorbent media or a chemical reactant (Section 4.1). The concentration is determined by the mass of analyte collected relative to the sampling rate and time. After the exposure period, the samplers are resealed and sent to a certified laboratory for analysis, following strict chain-of-custody procedures (Section 4.2, Guide D4840).
The standard integrates with a suite of critical ASTM standards to ensure comprehensive quality control across the sampling and analytical workflow:
| 🟦 Designation | 📏 Title |
|---|---|
| D1356 | Terminology Relating to Sampling and Analysis of Atmospheres |
| D1357 | Practice for Planning the Sampling of the Ambient Atmosphere |
| D3614 | Guide for Laboratories Engaged in Sampling and Analysis of Atmospheres and Emissions |
| D4840 | Guide for Sample Chain-of-Custody Procedures |
| D6196 | Practice for Choosing Sorbents, Sampling Parameters and Thermal Desorption Analytical Conditions for Monitoring Volatile Organic Chemicals in Air |
📊 Best Practices for Placement and Handling
Proper placement is critical for obtaining representative samples. Samplers must be located in the breathing zone of occupants and away from direct air currents or sources of contamination. The table below outlines the core operational characteristics of diffusive samplers as defined by the standard.
| ⚙️ Parameter | 📐 Specification / Guidance |
|---|---|
| Power Requirement | None (relies on molecular diffusion per Fick’s First Law, Section 1.3) |
| Environmental Scope | Non-industrial indoor settings (offices, homes, public buildings, Section 1.3) |
| Sampling Basis | Time-weighted average (TWA) concentration (Section 5.1) |
| Post-Exposure Protocol | Reseal immediately, ship to lab under chain-of-custody (Section 4.2, D4840) |
| Safety Responsibility | User must establish appropriate safety, health, and environmental practices (Section 1.6) |
⚠️ Environmental Limitations — D6306-17 is explicitly designed for non-industrial indoor environments. Users adapting this guide for industrial hygiene or ambient outdoor air must carefully evaluate the applicability and consult Guides D1357 and D3614 for additional planning and laboratory quality requirements.
❓ Frequently Asked Questions
🔍 What is the primary purpose of ASTM D6306-17?
It provides guidance on the placement and use of diffusive samplers for gaseous pollutants in indoor air to ensure uniformity of sampling, facilitate comparison of results, and measure occupant exposure concentrations.
💡 How does a diffusive sampler work without a pump?
It operates purely based on Fick’s first law of diffusion. Gaseous molecules move from an area of higher concentration (the ambient air) through a defined geometric opening into an area of lower concentration (the sorbent bed) without mechanical assistance.
⚡ What post-sampling procedures are critical for sample integrity?
The samplers must be immediately resealed after the exposure period to prevent further adsorption or loss of analytes. They must then be shipped to a qualified laboratory following rigorous chain-of-custody procedures, as specified in Guide D4840.
📌 What types of buildings does this standard apply to?
This standard is explicitly intended for non-industrial indoor environments, including residences, public buildings, and offices. It is not primarily intended for industrial or ambient (outdoor) atmospheric sampling without significant adaptation.