A New Approach to Flash Point Testing

insights from industryChristian Schröder-HolzhackerProduct Managereralytics GmbH

In this interview, industry expert Christian Schröder-Holzhacker provides an in-depth look at flash point testing, highlighting ​​​​​the growing global adoption of ASTM D7094 as a modern and safer alternative to traditional methods.

Can you briefly explain what flash point testing is and why it is so important across different industries?

First, it’s important to define what a flash point is. The flash point is the lowest temperature at which the vapors of a substance will ignite when exposed to an external ignition source. It’s important to note that it’s not the liquid itself that burns, but the vapor above it. The liquid needs to be heated to a specific temperature to generate enough vapor for combustion.

Flash point testing is a standardized way to measure this behavior under controlled conditions. It’s a critical tool in risk assessment because it indicates whether a material is classified as flammable, which has huge safety implications.

The flash point of a substance is relevant during production (like in the petroleum or fragrance industries), and for transport regulations. For example, diesel has a flash point of around 60 °C, which makes it relatively safe to handle. But gasoline, with a flash point of -35 °C, is highly flammable. So, the flash point helps define hazard levels and determine proper handling and transport regulations.

ASTM D93 (Pensky-Martens) has been a widely used standard for many years. What are some of its key characteristics and limitations?

ASTM D93, also known as the Pensky-Martens test method, is an established method and it is over 150 years old. It requires a sample volume of 70 mL and involves heating the liquid with a controlled rate, testing for ignition every one or two degrees Celsius using an open flame or a glowing wire.

While it's very standardized, it does have limitations. It typically doesn’t measure below 40°C—so it’s not ideal for materials with low flash points. It also requires a relatively large sample volume, which is problematic when working with expensive or hazardous materials.

This method is risky safety-wise because a temporarily open container with flammable vapor is exposed to an ignition source. If – by accident – a highly volatile and flammable substance like gasoline is measured, it can create a continuous flame that’s hard to extinguish.

ASTM D7094 is often described as a modern, safe, and fast alternative to ASTM D93. Can you explain the main differences between these two methods?

D93 and D7094 are closed-cup methods, but D7094 is a "continuously closed-cup" method. That means the sample cup remains sealed throughout the entire test. Instead of opening the cup to introduce an ignition source, we use a high-energy electrical arc—similar to a spark plug—which can ignite vapors without ever opening the system.

This design has big safety implications. Since the cup remains closed, there’s no risk of the sample continuing to burn – any combustion consumes the available oxygen inside the cup and extinguishes itself.

Another key difference is sample volume. D7094 only requires a 2 mL sample, compared to 70 mL in D93, which makes the whole device much smaller and more efficient.

Many industries rely on ASTM D93 for regulatory compliance. How does ASTM D7094 compare in terms of accuracy and repeatability? Can it serve as a direct replacement?

First, it’s important to understand that flash point is a method-defined parameter, meaning there’s no absolute reference value for comparison like there is with physical parameters, e.g. temperature or pressure. So, what matters is repeatability and reproducibility.

ASTM D7094 has shown significantly better repeatability in several inter-laboratory studies, especially at higher temperatures. The differences are minor for jet fuel or diesel (around 40-60 °C). However, for lubricants with a flash point of 200 °C, the D7094 method shows up to three times better repeatability than D93. This makes it highly suitable for industries where precision is crucial.

Overall, D7094 is accepted for many products, such as diesel, fuel oils, bio-blends, and kerosene. However, whether it can be a direct replacement depends on the regulatory or product specification. Some specifications still mandate D93, but the adoption of D7094 is growing steadily.

In terms of sample volume, ASTM D7094 requires significantly less than D93. How does this benefit both the user and the environment?

Handling just 2 mL of sample is much easier and safer than dealing with 70 mL. It reduces lab personnel's exposure to hazardous substances and minimizes the chance of spills. From a waste perspective, the difference is huge. If you are running 20-25 tests a day, that’s only about 50 mL of accumulated waste with D7094, compared to over 1.5 liters with D93. That’s a big difference in terms of disposal costs and environmental impact—especially for expensive or hazardous materials.

Have you seen any trends in the adoption of ASTM D7094 globally? Are regulatory bodies beginning to recognize it as an equivalent or even superior alternative?

Yes, definitely. ASTM D7094 has been around since the late 1990s and is now accepted in many fuel-related standards, including diesel, fuel oils, and kerosene. We're also working on getting it officially approved for jet fuel testing.

Organizations like ASTM and the EPA in the U.S. are generally quicker to adopt newer methods than some of their European counterparts, but progress is happening across the board. So it’s a transition phase, and we're seeing growing acceptance globally.

Automation and digital integration are becoming essential in modern labs. How does eralytics incorporate smart technology into its flash point testers?

At eralytics, we focus on flexibility and integration. We don’t provide a LIMS (Laboratory Information Management System) software ourselves, but we make sure our analyzers can connect easily to all major LIMS systems. That means supporting multiple interfaces—Ethernet, RS-232, USB, and more.

This applies to our flash point testers and the entire eralytics product portfolio. We aim to future-proof our devices so that labs can easily integrate them into their existing systems without needing custom workarounds.

Image Credit: eralytics GmbH

Beyond petroleum, are there any other industries or applications where ASTM D7094 is gaining traction?

Yes—aside from petroleum, a big industry for flash point testing is flavor and fragrance, especially in countries like France. In this sector, the cost of samples becomes a much bigger factor. Testing 70 mL of a high-end perfume might cost hundreds of euros while testing 2 mL is far more economical.

So, in addition to the safety and environmental benefits, D7094's cost advantage makes it a clear choice for industries dealing with expensive or specialty chemicals.

Are there any specific geographic hotspots where demand for D7094 is strongest?

Demand is global - our flash point testers are used in over 150 countries. Of course, major markets like the U.S. and China are big for us, but we see adoption in Southeast Asia, Europe, and beyond. Flash point testing is relevant across various industries and geographies, so there isn’t a single hotspot; it’s a universal need.

Are there any final insights you’d like to share with labs or industries considering a move to ASTM D7094 and eralytics’ solutions?

The key considerations are safety, convenience, and compliance. If you can choose your test method, D7094 offers clear advantages in safety, sample handling, and waste reduction.

However, if you are tied to certain product specifications or regulatory frameworks, you may still need to use D93. That being said, the landscape is evolving, and more and more specifications are being updated to include or allow D7094. So, it is a good time to start exploring modern alternatives.

Image Credit: eralytics GmbH

Image Credit: eralytics GmbH

About Christian Schröder-Holzhacker 

Christian Schröder-Holzhacker is a Product Manager at eralytics GmbH, based in Vienna, Austria. With a Ph.D. in Chemistry from the Vienna University of Technology, he combines scientific expertise with hands-on experience in analytical instrumentation.

With over 7 years of experience in the field, his work bridges innovation, safety, and regulatory compliance across industries. Christian is passionate about modernizing laboratory practices, and he actively supports the adoption of smart, efficient alternatives to traditional testing methods.