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1.8 Platform for Internet Content Selection (PICS)

Publishing date: May 2002

The W3C Platform for Internet Content Selection (PICS) specification allows web managers to set a certification rating for the content of their sites. This is very similar to the ratings system that exists for films shown in cinemas.

A filter configured to use the PICS ratings system will read the classification contained within the data and displays the page only if it meets the user-defined specifications.

Use each checklist to ensure that your web pages comply with these guidelines

1.8.1 Checklist and summary: Core guidance

Checklist

Summary

The ICRA system allows the author of a page or site, through the use of a specific metatag, to identify content of the website or document in each of the following categories:

The rating system uses a neutral binary system. A particular element within each category, such as, ‘mild expletives’ in the language section is either present or absent from the website.

1.8.2 Implementation

There are a number of varieties of PICS ratings systems on the Internet but the most commonly used is the ICRA system managed by the Internet Content Rating Association. Microsoft Internet Explorer and a growing number of filtering products support this.

Important - A rating can be chosen to cover the entire site, which can be added to the site’s homepage. If desired, each individual page can be separately certified. The usual practice is to certify only the site as a whole.

It would be expected that the majority of UK public sector web information sites would have a none of the above rating for each of the categories in the ICRA system.

There are two basic steps to using this system. First, the content manager will obtain a rating label (a metatag) for the site and will then add that to the source data of the default page in the domain. This is usually called index.htm and may be a frameset. Second, the user’s web browser or filter can be configured to read that PICS certification.

Once turned on, the PICS rating and filtering system can be a very strong tool in restricting the websites that are accessible. If a page has a higher rating than that set by the owner of the browser, the user is requested to insert a password. Only the correct password will allow the page to be downloaded and displayed.

W3C PICS standard http://www.w3.org/PICS/ [External link]

1.8.3 Gaining a label

To gain an ICRA label for your site you must visit the following URL:

http://www.icra.org/_en/label [External link]

  • Once at the site select the ‘Label your website here’ button.
  • You now have the ability to certify a single page, a directory or an entire website. Select the option that is most suitable.
  • You will now need to complete the Registration document.
  • On this page you will be asked to identify the content of your website or the web page descriptors in each of the ICRA categories. When this section is completed click on the ‘Submit’ button at the bottom of the page.
  • You will now need to confirm or change any of the entered data in the ‘Input Verification’ page. When completed click the ‘Input correct’ button.
  • Finally the user must agree to the ICRA Terms and Conditions document by selecting the button at the bottom of the page.
  • Once completed the ICRA rating will be displayed with instructions on how to incorporate the metatag into your chosen pages. The site includes extra support information should it be needed and runs a free email technical support service.

Key points about labelling:

  • A filter will read and cache labels it finds. It will not ‘search the site’ for labels. Therefore if there are commonly used entry points to the site other than the home page; these too should carry a copy of the label.
  • Pages always accessed through links from within the site do not need to be labelled separately as the cached label will be used.
  • ICRA’s support pages include a flow diagram of how labels are read and interpreted by filtering software.

1.8.4 Example of a PICS metatag

The following is an example of the standard PICS metatag generated from the ICRA site. The URL in bold will need to reflect the page in which the metatag is to be inserted, not the example department URL as is illustrated here.

In this example, the rating (defined in the parentheses) is ‘none of the above’ in all categories - the website contains neither sex nor violence, etc. The tag includes elements for backward compatibility with ICRA’s forerunner - RSACi.

Once this rating has been achieved the website can display the ICRA logo on the homepage to illustrate that the procedure has been completed. This is optional and a range of different colours is available.

More complex example to show flexibility

This metatag does not specify the page or site to which it applies. Such a PICS label will be applied only to the page it is on. Furthermore, note that the lz 1 term (which is ICRA code for “none of the above” in the language category) has been set to lz 0. This means that the label does not make a positive declaration that there is no potentially offensive material on this page. Such a label might be useful, for example, for pages which carry quoted speech including swear words but which most readers would not deem “offensive” in the context given. You can make analogous changes in other categories.

Labels may be edited at will -- but watch the syntax! ICRA does not need to be informed about every change made and has other tools available that may be useful.

The e-Government Interoperability Framework can be found at:

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