GLP-Compliant Vapour Pressure Testing According to OECD 104

LAUS performs GLP-compliant vapour pressure testing according to OECD 104 to provide high-quality experimental physicochemical data for regulatory submissions and chemical safety assessments.

We have experience in the determination of vapour pressure for challenging test items, including substances with very low vapour pressures and complex substances such as mixtures and UVCBs. A particular capability of our laboratory is the determination of extremely low vapour pressures down to 10⁻¹⁰ Pa using the Effusion Method with a Knudsen Cell. This approach is particularly suitable for solid substances with low volatility and a known molecular weight.

Selecting the Appropriate OECD 104 Method

OECD Test Guideline 104 – Vapour Pressure is part of OECD Guidelines for the Testing of Chemicals, Section 1: Physical-Chemical Properties. Depending on the substance and expected vapour pressure, an appropriate method is selected to generate reliable and scientifically sound data.

Effusion Method (Knudsen Cell)

•    Pressure range: 10⁻¹⁰ to 1 Pa

•    Particularly suitable for substances with very low vapour pressures

•    Vapour pressure is determined based on the measured mass loss of the test substance

•    Suitable for solid substances with known molecular weight

•    For UVCBs and mixtures, a vapour pressure range can be reported

The ability to determine vapour pressures as low as 10⁻¹⁰ Pa represents a particular analytical capability of LAUS and enables the testing of substances whose vapour pressure is difficult to measure using conventional methods.

Static Method

•    Pressure range: 10 to 10⁵ Pa

•    Suitable for substances with vapour pressures higher than that of water

•    Can also be applied to substances for which the molecular weight is not known

•    Pressure is measured directly at defined temperatures

•    Endpoint: Vapour pressure at 20 °C and 25 °C, calculated from the experimental measurements

Endpoint

Vapour pressure at 20 °C and 25 °C, calculated from the experimental measurements

OECD 104 Vapour Pressure Testing at LAUS

Looking for a reliable laboratory for OECD 104 vapour pressure testing?

LAUS can support your project with GLP-compliant testing and scientifically sound study design for a wide range of chemical substances. Contact our scientists to discuss your test item, expected vapour pressure range and study requirements.

Request a quote for OECD 104 Vapour Pressure Testing.

Your Benefits at LAUS

•    OECD 104 vapour pressure testing under GLP

•    Effusion method using a Knudsen cell

•    Measurement of extremely low vapour pressures down to 10⁻¹⁰ Pa

•    Static method for higher vapour pressures

•    Experience with mixtures and UVCBs

•    Individual selection of the most appropriate test method

•    Reliable experimental data for regulatory applications

Frequently Asked Questions about OECD 104 Vapour Pressure Testing

What is vapour pressure?

Vapour pressure is the pressure exerted by the gas phase of a substance when it is in equilibrium with its condensed phase at a given temperature. It is an important parameter for assessing the volatility of a substance.

What is OECD Test Guideline 104?

OECD Test Guideline 104 – Vapour Pressure describes standardised methods for the experimental determination of the vapour pressure of chemical substances.

Which method is suitable for very low vapour pressures?

For very low vapour pressures, the effusion method using a Knudsen cell is particularly suitable. At LAUS, vapour pressures as low as 10⁻¹⁰ Pa can be determined using this method.

Can mixtures and UVCBs also be tested?

Yes. LAUS has experience with mixtures, multi-constituent substances and UVCBs. Depending on the test item, a vapour pressure range can, for example, be determined.

Can substances with an unknown molecular weight be tested?

Yes. For suitable test items, the static method can be used. In this method, the pressure is measured directly at defined temperatures, so a known molecular weight is not required.

Are OECD 104 vapour pressure tests performed under GLP at LAUS?

Yes. LAUS performs vapour pressure testing according to OECD 104 under Good Laboratory Practice (GLP).