Institute for Interlaboratory Studies

The independent institute organizes global interlaboratory studies on fuels, petroleum products, petrochemicals and consumer products. Studies are usually performed on commercially relevant products and involve testing on complete specifications. Any laboratory may participate using its own routine analytical methods.

Discover our annual program

Petroleum products

CHEMICALS
FUELS
GASES
LUBRICANTS and OILS
PETROLEUM PRODUCTS and OTHERS

Consumer products

COSMETICS AND PERSONAL CARE
LEATHER/FOOTWEAR
POLYMERS
TEXTILES
FOOD AND SKIN CONTACT MATERIAL, TOYS, DRIED PAINT

How it works

The process

Register your account

After your registration, followed by authorization by iis, you can proceed with ordering PT-products.

Order your products

Participation in some PTs may be limited due to limited stock of products. We therefore highly recommend to apply your PT-registration as soon as possible. Dispatch costs will be calculated afterwards, this will vary per product and destination.

Product dispatch

Once your participation is confirmed, we will ship the products to the address of your choice.

Confirm product receipt

You can confirm product receipt via your client account or the iis Data Reporting portal.

Report your test results

You can submit your test results via the iis Data Reporting portal.

Reports & Certificates

You will receive your Proficiency Test Report and you can download your certificates in your account. We use our protocol to run a Proficiency Test.

About us

Who we are

iis is an independent organization that provides various types of interlaboratory studies (proficiency tests, round robins, cross checks, collaborative trials) for analytical laboratories. The Institute is located in Spijkenisse - The Netherlands. Its clients - participating laboratories in interlaboratory studies - are found all over the world, in more than 100 countries.

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most recent iis Topics

July 10, 2025

Updated Overview of Costs and General Conditions SGS Nederland B.V.

Please be informed that the cost overview of Petroleum products and Consumer products have been reviewed and updated. Additionally, the General Conditions of SGS Nederland B.V. have recently been revised,...

New iis Data Reporting website in use

The new iis Data Reporting website here will be available from the following PTs that will start this week: Fuel Oil iis25F01 Fuel Oil Metals iis25F01M Fuel Oil Chemical Species...