SUNTEST CPS/CPS+ conforming to the COLIPA Guideline: “METHOD FOR THE IN VITRO DETERMINATION OF UVA PROTECTION PROVIDED BY SUNSCREEN PRODUCTS” (Edition 2007A)
Note: The previous SUNTEST XLS/XLS+ model (built until 2008) was an accepted ‘solar simulator’ for the COLIPA 2007A test. The 2008 redesigned SUNTEST XLS+ has not been validated for the stated in-vitro method. Atlas MTT solely recommends the use of the SUNTEST CPS/CPS+ instrument in combination with the SunTray accessory.
BACKGROUND
COLIPA is the European trade association representing the interests of the cosmetic, toiletry, and perfumery
industry. As a non-profit-making organisation, COLIPA develops guidelines and test methods to promote reliable
In the past, the level of protection for sun protection products has been indicated by the sun protection factor
(SPF). The SPF number is influenced primarily by UVB wavelengths and the test is performed on human
In recent years, the harmful effects of the UVA wavelengths of sunlight have been more thoroughly established.
This has resulted in a new common method to test the effectiveness level of sun protection products to UVA
wavelengths. The method for the separate assessment of a sunscreen product’s ability to protect against UVA
exposure is based on an in vitro methodology.
The Atlas® SUNTEST is mentioned as an appropriate solar simulator. The new method comes with an Excel file
including several spreadsheets that have to be filled in with equipment and test data by the user. The results,
including the determinate UVA sun protection factor, are obtained by the automatic calculation function in the
The following describes some of the practical aspects of the procedures using a SUNTEST CPS/CPS+ in combination with the SunTray accessory.
PROCEDURE
UVB is defined as 290 – 320 nm and UVA as 320 – 400 nm.
The COLIPA 2007A method describes the UV source for pre-irradiation as:
Light source specifications as measured spectroradiometrically Total UV irradiance (290 to 400 nm) Irradiance ratio of UVA(320 to 400 nm) to UVB(290 to 320 nm)
The Atlas SUNTEST instruments CPS/CPS+ and XLS/XLS+ (built until 2008) are mentioned as examples of
appropriate UV radiation sources. The filter combination specified is:
IRRADIANCE CALIBRATION
To maintain an equal quality of UV sources COLIPA has published the “Guidelines for Monitoring UV Radiation
Sources”. This guideline describes the calibration procedures for instruments with UV sources and is an essential
part of the 2007A method of UVA-PF determination.
“The emission of the solar simulator will be checked (at least) annually for compliance with the given acceptance limits by a suitably qualified expert. The inspection should be conducted with a spectroradiometer that has been calibrated against an internationally accepted calibration standard.” and B) “Between two inspections the emission of the solar simulator will be monitored radiometrically (e.g. with an integrated UV meter). In parallel with the control of the UV source spectrum, the radiometer(s) and UVA cell(s), usually employed for controlling or adjusting the irradiance of the UV source at sample level and calculating the UV doses, will be calibrated in terms of UVA irradiance (W/m² UVA, 320-400 nm) for the same UV source spectrum, according to the COLIPA recommendations given in the Guideline "Monitoring of UV light sources" (2007). For A). The radiometric laboratory of Atlas MTT in Germany is a COLIPA accepted expert; the laboratory is
accredited to provide this service. New instruments can be calibrated according the COLIPA Guideline before
shipment enabling the customer to start testing immediately. The SUNTEST instrument then comes with an
official certificate. For the annual compliance check, a local COLIPA accepted expert needs to be called; a list of
accepted experts is available at COLIPA. More information on accredited laboratories can be found at:
http://www.npl.co.uk/optical_radiation/publications/orcs/spectroradiometry.pdf.
For B). The integrated UV meter of the SUNTEST can be checked using a XenoCal BB 300 – 400 nm. The
certificate (see A) provides the information on the UVA to UVB ratio enabling the customer to enter the necessary
information into the COLIPA Excel spreadsheet. The regular XenoCal measurements can be checked and
compared to the radiometric results of the Atlas MTT laboratory in Germany or can be compared to the
measurements of the local expert or external accredited national laboratory on an annual base.
PRACTICE
The test procedure specifies to test at least three samples of each tested product. The exposure time per sample
is calculated by the COLIPA Excel program and is based on irradiance level, product characteristics, and the
amount of product being tested. The 2007A method does not specify the irradiance level. The SUNTEST can be
operated on selectable irradiance levels. Therefore, exposure durations differ accordingly. Test durations are
typically short, <15 – 20 minutes. Therefore, to be able to operate a SUNTEST CPS/CPS+ in continuous light
mode, Atlas has developed the SunTray accessory. To avoid disturbing the test by opening the SUNTEST
repeatedly, Atlas recommends the use of the SunTray. SunTray is a device that enables the user to remove or
exchange samples from the SUNTEST test chamber without stopping the SUNTEST and not being exposed to
The COLIPA 2007A method specifies a sample temperature below 40°C to reduce thermal effects. Atlas
recommends the use of a SunCool device in order to maintain the sample temperature on a constant (low) level
If no SunCool is available, Atlas recommends reducing the irradiance to a low set point e.g. 500 W/m² (300-
800nm) and the set point of the BST (Black Standard Temperature) of 0°C resulting a maximum airflow over the
samples for a maximum cooling effect. The Black Standard Temperature sensor should then be removed from the
test chamber and placed under the sample table in the SUNTEST. The SUNTEST unit will continue to run at
maximum fan speed resulting in maximum cooling effect on the sample surface.
If the COLIPA test is carried out in a SUNTEST CPS/CPS+ unit combined with a SunTray unit, the Black
Standard Temperature should be set to 0°C and the BST sensor placed in the SunTray drawer below the sample
Example I: Start-up of new SUNTEST CPS+
The Atlas calibration certificate states for example:
Conversion factor to convert SUNTEST 300-800 nm to UVA 320-400 nm is 0.01275 Note: the conversion factor instrument dependent and not universal.
• This conversion factor must be entered in cell E27 of the RESULTS Worksheet • The customer operates its SUNTEST with irradiance for example 510 W/m² 300-800nm
(Colipa specifies minimum value 500 W/m²)
• This irradiance value has to be entered in the Excel spreadsheet in cell D27 on the RESULTS Worksheet • The COLIPA program uses the calculated value of cell F27 (= UVA320-400nm in mW/cm²) Example II: Regular check of SUNTEST CPS+ using XenoCalBB300-400
The Atlas certificate of the new instrument or the certificate of the local COLIPA expert (annual base) states
Operating the SUNTEST with irradiance set at 500 W/m² 300 – 800 nm
Total UV irradiance is 51.0 W/m2 ratio of UVA : UVB is 15.0
• SUNTEST operated with irradiance 500 W/m² 300-800nm • A regular measurement with XenoCal BB 300 – 400 shows UV irradiance is 51.2 W/m² 290 – 400 nm • The
320 – 400 nm portion of the irradiance is (15/16) x 51.2 = 48.0 W/m² 320 – 400 nm
• This irradiance value has to be entered in the Excel spreadsheet in cell D27 on the RESULTS
Worksheet. The COLIPA Excel program requires a value in mW/cm², the conversion factor in cell E27
of the RESULTS Worksheet is therefore set to 0.1
Example III: Regular check with local Colipa expert
The certificate of the local COLIPA expert (annual base) states for example:
Ratio of UVA : UVB is newly determined for example 18.2 UVA 320-400nm irradiance is 4.8 mW/cm²
• SUNTEST operated with irradiance 500 W/m² 300-800nm • A regular measurement with device of local expert shows UVA irradiance is 4.8 mW/cm² 320 – 400 nm • This irradiance value has to be entered in the Excel spreadsheet in cell D27 on the RESULTS Worksheet • The conversion factor of cell E27 of the RESULTS Worksheet is set to 1.0 unless the local expert
Application and experience of CAN as a low cost OBDH bus system MAPLD 2004, Washington D.C. USA, 8th – 10th September, 2004 Surrey Satel ite Technology Ltd, University of Surrey, Guildford, GU2 7XH, UK. Abstract This paper gives an overview of Surrey Satel ite Technology Ltd. (SSTL) use of CAN bus on its recent missions. It gives a description of the SSTL CAN topology and goes i