ASTM D1739 Explained: A Practical Guide to Dustfall Monitoring
What Is ASTM D1739?
ASTM D1739 is a standard test method for the collection and measurement of dustfall, also known as settleable particulate matter.
The current edition is ASTM D1739-98(2026), published by ASTM International. The method provides a procedure for collecting dustfall from ambient air and determining the amount of particulate matter deposited over a specified monitoring period. It covers both water-soluble and insoluble particulate matter.
Unlike instruments that continuously measure airborne particulate concentrations, ASTM D1739 uses a relatively simple collection method. A suitable collection container is exposed at a monitoring location, allowing particles that settle from the atmosphere to accumulate. The collected material is subsequently processed and weighed.
This makes ASTM D1739 particularly useful for long-term dustfall monitoring and trend assessment.
What Does ASTM D1739 Measure?
ASTM D1739 is concerned with settleable particulate matter—particles that are sufficiently large or heavy to settle out of the atmosphere under gravity.
The method determines the mass of material collected over the monitoring period. The historical procedure describes reporting the result as a dustfall rate, commonly expressed in:
g/(m² · 30 days)
This expresses the mass of deposited particulate matter per square metre over a 30-day period.
It is important to distinguish dustfall from airborne particulate measurements such as PM10 and PM2.5. PM10 and PM2.5 monitoring focuses on particles suspended in the air within defined aerodynamic size fractions, whereas dustfall monitoring measures material that deposits onto a collection surface.
How Does the ASTM D1739 Dustfall Method Work?
The basic principle is straightforward.
A dustfall collection container is positioned at a carefully selected monitoring location and exposed to the surrounding atmosphere. During the sampling period, settleable particles fall into the container.
At the end of the sampling period, the container is closed and returned for laboratory processing. The collected material is separated into its relevant components, including water-soluble and insoluble material, and the quantities are determined.
The earlier published procedure describes a monitoring period of approximately 30 days and reporting the results in grams per square metre per 30 days.
The simplicity of this approach is one of its main advantages. ASTM itself describes the method as simple and useful for studying long-term trends, while also noting that it is a crude and non-specific method.
What Equipment Is Needed for ASTM D1739?
An ASTM D1739 dustfall monitoring programme generally requires:
- Dustfall collection containers
- Suitable container supports or monitoring stands
- Clearly identified monitoring locations
- Appropriate sample handling and storage equipment
- Laboratory equipment for processing and weighing samples
- Documentation for recording sampling dates, locations and conditions
The design and installation of the monitoring equipment are important because the objective is to obtain representative samples of dust deposition while minimising interference from the monitoring apparatus itself.
For environmental dust monitoring programmes, equipment may also be configured to provide directional information, allowing dust deposition to be assessed in relation to potential source locations.
Where Is ASTM D1739 Used?
Dustfall monitoring can be useful in situations where understanding the longer-term deposition of particulate matter is important.
Typical applications include:
- Mining operations
- Quarries
- Construction sites
- Bulk material handling facilities
- Industrial facilities
- Mineral processing operations
- Roads and haul routes
- Agricultural and other dust-generating activities
- Environmental impact monitoring
- Community dust monitoring programmes
The method can provide a useful record of how much settleable particulate matter is being deposited at different monitoring locations over time.
For a site with multiple potential dust sources, several monitoring stations can be used to establish spatial patterns and identify changes in deposition.
ASTM D1739 and Long-Term Dust Trends
One of the strengths of ASTM D1739 is its suitability for long-term trend monitoring.
Because the method collects deposited material over an extended sampling period, individual results can be compared between monitoring locations and across successive sampling periods.
For example, a monitoring programme might reveal:
- Increasing dust deposition at a particular boundary location
- Seasonal changes in dustfall
- Differences between upwind and downwind locations
- Changes following the introduction of dust-control measures
- Long-term changes associated with site activities
A well-designed monitoring network therefore provides more information than a single isolated dustfall result.
What Are the Limitations of ASTM D1739?
ASTM D1739 is useful, but it is important to understand what the method is not designed to do.
The current ASTM scope states that the method is not appropriate for determining dustfall rates in small areas affected by specific sources. It also states that the method is inappropriate for industrial hygiene applications except where other, more specific methods are used.
This distinction matters.
ASTM D1739 is primarily an environmental dustfall collection and measurement method. It should not automatically be treated as a method for measuring worker exposure to airborne dust.
Similarly, a dustfall collector does not provide the same information as a real-time particulate monitor. If the objective is to measure airborne PM10, PM2.5, respirable dust or occupational exposure, a different measurement approach may be required.
ASTM D1739 vs PM10 Monitoring
It is common to confuse dustfall monitoring with PM10 monitoring, but the two measure different things.
ASTM D1739 dustfall monitoring:
- Measures particulate matter that settles from the atmosphere
- Provides a deposition rate over a sampling period
- Is well suited to long-term environmental trend monitoring
- Uses passive collection rather than continuous real-time measurement
PM10 monitoring:
- Measures airborne particulate matter within the PM10 size fraction
- Can use active sampling or continuous monitoring instruments
- Provides information about particles suspended in ambient air
- Is generally used when airborne particulate concentration is the parameter of interest
Both approaches can be valuable, but they answer different environmental monitoring questions.
Why Is Correct Monitoring Location Important?
The location of a dustfall collector can have a major influence on the information obtained from a monitoring programme.
Monitoring locations should be selected with consideration given to:
- Potential dust sources
- Prevailing wind direction
- Property boundaries
- Nearby residential or sensitive areas
- Terrain and surrounding structures
- Site activities
- Background conditions
- Accessibility and security
A network containing multiple sampling points can provide considerably more information than a single collection point.
Where the purpose of monitoring is to understand the contribution of a particular source, monitoring design becomes especially important because a conventional dustfall sample can contain material originating from multiple sources.
ASTM D1739 in South African Dustfall Monitoring
ASTM D1739 is particularly relevant to environmental dust monitoring in South Africa. South African guidance and regulatory material has historically referenced ASTM D1739 in connection with dustfall monitoring. The dust-monitoring industry also commonly uses the method as a basis for environmental fallout-dust monitoring programmes.
However, applicable legislation, permits, environmental authorisations and project-specific monitoring requirements should always be checked before selecting a monitoring method or interpreting a result.
The applicable regulatory requirements may specify monitoring locations, action levels, reporting requirements or other conditions in addition to the measurement method itself.
What Is the Current ASTM D1739 Edition?
An important point when researching ASTM D1739 online is that older references remain widely available.
The current edition is:
- ASTM D1739-98(2026) — Standard Test Method for Collection and Measurement of Dustfall (Settleable Particulate Matter).
ASTM lists the 2026 edition as active and identifies the 2017, 2010 and earlier editions as previous versions.
Consequently, documents, websites or monitoring specifications that refer to ASTM D1739-98(2010) or ASTM D1739-98(2017) may be referring to historical versions of the standard.
For compliance work, users should verify which edition is specified by the applicable regulator, permit, project specification or monitoring programme.
ASTM D1739: Simple Method, Useful Data
The main attraction of ASTM D1739 is its simplicity.
A properly designed dustfall monitoring programme can provide a relatively straightforward way of documenting the amount of settleable particulate matter deposited at selected locations over time.
Its value is particularly apparent when multiple monitoring stations are operated consistently and the results are evaluated as a time series rather than as isolated measurements.
At the same time, the limitations of the method should be understood. ASTM D1739 itself identifies the method as crude and non-specific and states that it is useful for studying long-term trends.
Choosing Dust Monitoring Equipment for ASTM D1739
The monitoring equipment should be appropriate for the environmental conditions, monitoring objectives and applicable specification.
When selecting a dustfall monitoring system, consider:
- Compliance with the required monitoring method
- Collector design
- Container dimensions
- Mounting and support arrangements
- Protection from interference and contamination
- Ease of sample removal and replacement
- Site security
- Resistance to weather and corrosion
- Ease of cleaning and maintenance
- Ability to operate multiple monitoring stations consistently
For programmes involving several monitoring points, a robust and repeatable equipment design can make routine sample collection and maintenance significantly easier.
Frequently Asked Questions About ASTM D1739
Is ASTM D1739 a dust monitoring standard?
Yes. ASTM D1739 is a standard test method for the collection and measurement of dustfall or settleable particulate matter.
How long is an ASTM D1739 sample collected?
The traditional procedure uses a sampling period of approximately 30 days, with results reported on a 30-day basis.
Does ASTM D1739 measure PM10?
No. ASTM D1739 measures settleable particulate matter deposited into a collection container. It is not a PM10 concentration measurement method.
Can ASTM D1739 be used for occupational dust exposure?
ASTM states that the method is inappropriate for industrial hygiene use except where other, more specific methods are also used.
What units are used for ASTM D1739 dustfall?
The traditional reporting format is a mass deposition rate, commonly grams per square metre per 30 days (g/m²/30 days).
Is ASTM D1739 still current?
Yes. The current ASTM edition is ASTM D1739-98(2026), which ASTM lists as active.
Conclusion
ASTM D1739 provides a practical method for collecting and measuring dustfall, or settleable particulate matter, from ambient air. Its simplicity makes it particularly useful for long-term environmental dustfall monitoring and trend analysis.
However, ASTM D1739 should be selected with a clear understanding of its scope and limitations. It is a dustfall deposition method rather than a real-time airborne particulate monitor or an occupational exposure measurement method.
For organisations operating mining, quarrying, industrial or other dust-generating sites, a properly designed dustfall monitoring network can provide valuable information about particulate deposition and changes over time.
When selecting dust monitoring equipment for ASTM D1739, the collector design, installation, monitoring locations and sampling procedures should all be considered as part of the overall monitoring programme.
For ASTM D1739 dustfall monitoring equipment and environmental dust monitoring solutions, explore the equipment available from Dust Monitoring Equipment.
At Dust Monitoring Equipment, we specialise in fallout dust monitoring equipment, training and services for organisations requiring practical solutions for dustfall monitoring.
For more information on dustfall monitoring equipment and services, contact our team to discuss your monitoring requirements.
