Call for Interest – to Evaluate Alternative SPF Methods

Deadline extended until 1 September, 2020

Learn more about ALT-SPF

Learn more about the ALT-SPF Consortium by reading the interview with Jürgen Vollhardt (Global Head of Science & Promotion Sun Care at DSM, Member of ISO TC217/WG7 for SNV) and Uli Osterwalder (Principal and Owner at Sun Protection Facilitator GmbH, Chair of ISO TC217) for the SOFW Journal.

Context and aim of the ALT-SPF initiative

The ALT-SPF project purpose is to evaluate, characterize and compare several alternative SPF test methods to ISO 24444:2019 and to publish the results obtained in peer-reviewed journal(s).

Rationale and brief history


The SPF procedure as described in ISO 24444:2019 and the quite comparable procedure in the US as defined by the FDA for SPF measurement are labor-intensive and complex human tests. The UV challenge to the subjects is on a small area but can bear considerable dosages, which is why there has long been a desire for alternative methods. Moreover, the complexity of the procedure and some intrinsic variabilities of this biological test (human subjects, human sunscreen application and human readout) create, for validation purposes, a relatively large random variability, in particular, between different laboratories performing these tests.

Skin cancer incidence rates are still growing around the globe and there are not many silver streams on the horizon that this trend diminishes. The SPF value, measured on human skin, represents a number that is intrinsically linked with the protection against DNA damage in human skin and thus it is connected with the protective ability of sunscreens against skin cancer, although, application of sunscreens should not be the only strategy against the disease. An alternative SPF test method should therefore deliver at least equivalent results as the current SPF in vivo in terms of accuracy and there is on top the desire, that the new method shows improvements in precision (repeatability and reproducibility), is easy to adapt by laboratories and cost-effective to perform.

Over the last two to three decades alternative methods such as for example, in vitro transmission tests in silico calculation, or non-invasive in vivo testing (using negligible UV dose on humans) have emerged and been developed to a stage that makes them promising alternatives.

The desire to understand the precision behavior of the alternative methods demand sophisticated statistical tools to analyze and, in particular, to characterize them for a general public use. These statistical tools aim to deliver key features to rate accuracy and to measure reproducibility, degree of systematic errors against different categories of sunscreens. The accuracy, repeatability and reproducibility should be known to decide on the release of a method measuring protective abilities of sunscreens that are linked to skin cancer prevention.

Comparing alternative SPF data against the gold standard requires a solid set of in vivo SPF data and thus represents a significant experimental effort that should not be repeated for each alternative method. This is how, in 2018, the main idea for the ALT-SPF project was born.

More information about the initiative can be found in the project synopsis.


Why should we as a personal care company sponsor this initiative?

As a personal care company sponsoring this initiative, you:

  • Get access to a huge amount of data on the characterization of alternative SPF test methods.
  • Will get to know the performance of the new methods in detail and for different product categories firsthand and can make your technology selection for you claiming needs.
  • Will be able to contribute to shaping the way alternative methods are characterized.
  • Can influence the samples that will be included.
  • Can interact with ISO experts working on the alternative methods.
  • Can spell out your expectation regarding bias and precision.
  • Will understand why the characterization method would withstand court challenges as it will be done according to the latest technology in statistics and various norms published or in preparation.
  • Will help providing the industry with a fast and reliable method that will also support your development process better.
  • Will support the in-depth investigation of the methods down to sample specific bias, their variation features relative to in vivo and that way defining properly the applicability and the scope of the new methods.
Does signing the Letter of Commitment (LoC) mean that my company is obliged to later sign the consortium agreement?

The LoC is necessary to screen for interested parties to join the consortium. Those who signed it will take part in the discussion to set up the consortium and shape the project before its actual launch. 

There is no obligation to later sign the consortium agreement by signing the LoC. However, the LoC asks you for confidentiality of information that is generated or distributed during the discussion phase prior to the project launch and the signature of the consortium agreement. If your company finally decides not to participate in the project, you are obliged to keep the shared information confidential.

Estimated timetable for the project execution

  • SPF Sample distribution: November 2020
    • Testing: November 2020 – May 2021
      • Publication of results: End of 2021

Who should participate?

This call for interest has for aim to invite the following interested parties to express their interest to join the consortium:

(i) any interested organization active in the manufacturing of sunscreens or UV filters; and/or

(ii) any interested organization active in alternative methods development to ISO 24444:2019 that fulfills the following cumulative criteria:

  • be able to provide scientific evidence that the alternative method shows agreement with SPF in vivo (ideally according to ISO 24444); and
Call for Interest – to Evaluate Alternative SPF Methods
  • willing to carry the efforts to provide test data and costs for individual statistical analysis and reporting, if required; and
  • be able to provide adequate number of laboratories to test, using the alternative method, the agreed number of sunscreen samples, following the agreed statistical approach (instructions to be agreed by consortium members after the call closure).

Any interested parties under (ii) may apply as a single applicant or in collaboration with other laboratories.

 The contribution of partners can be done in three ways:

  1. Sponsoring of project costs (a fixed amount to be calculated based on budget and number of sponsors before project launch).
  2. In-kind contribution by carrying out testing using alternative methods.
  3. Both 1 and 2.

Please note that the contribution under the conditions set forth in point 2 will give the right to participation to consortium meetings but no voting rights.


How to apply?

Submit both documents to the project manager ARTTIC: alt-spf-coordination [at]

Calendar for the call for interest and consortium setup

  • Extended deadline for submission of expression of interest: 1 September 2020
  • Communication of results of the evaluation of expressions of interest and invitation to participate in a first consortium meeting : 7 September 2020
  • First consortium meeting : End of September 2020
  • Signature of a Consortium Agreement: End of October 2020


For questions about the call, please contact:

alt-spf-coordination [at]

For questions about the organization/management of the project, please contact:

 Sara Skogsater, ARTTIC, email: skogsater [at]

 For more information related the technical aspects of the project, please contact:

Jürgen Vollhardt, DSM, email: Juergen.Vollhardt [at]

Uli Ostenwalder, SPF, email: uli.osterwalder [at]