A simple plan to offer children protection from harmful and inappropriate internet footage by clearly rating it with traffic light symbols is to be tested this summer. The project, developed by the British Board of Film Classification in collaboration with partners in Italy and the Netherlands, could also allow powerful internet service providers and search engines a new path through the current controversy about their unregulated content.

Amateur film-makers will be able to rate the films they put online according to national ratings categories, and the whole process could then be further policed by users of the site.

Participating websites would have the option of letting viewers comment on the way that each film has been rated, alerting both users and the relevant national authorities to any serious transgressions.

The idea of offering a do-it-yourself rating service for user-generated content came out of international discussions with the parallel bodies in charge of film censorship and classification.

"This is a service we want to offer," said David Austin, assistant director of policy and public affairs at the BBFC. "We already classify some 10,000 videos and films that are submitted to us for release every year and we will be using much the same classification model in the pilot for user-generated content."

The sheer amount of private video footage uploaded on popular sites such as YouTube means there is no way any board could tackle it. "The volume is so great that it became clear the answer was to get those who are making and posting the films to rate them for users," said Austin.

Consultation with the Dutch film regulator led to the idea that an online questionnaire comprising simple questions about the nature of the content could be made to apply across international boundaries.

"What the questions will do is provide a way of giving content an age rating. This is something that could be done in other countries in the world because, while the questionnaire can remain the same, the results will mean different things in different countries, since they all have different standards and film categories. Results in the Netherlands, for example, will reflect Dutch standards."

Austin explained that each country has varying levels of sensitivity to key issues such as swearing or nudity. "In Britain people don't generally like bad language, whereas in the Netherlands they don't care as much.

"We will not be asking people to make value judgments about their films. They just have to answer simple questions about the content, such as 'Does this video contain X, Y or Z, and if so, how long is the scene?'"

In Britain the usual six ratings categories for films will be reduced to three for ease of use. "We felt that six would be too complicated," said Austin, "so we have conflated U, which means suitable for all, with PG, parental guidance, and then the age category 12 with 15, and finally 18, suitable only for adults, with R18, which covers those adult works intended for licensed premises only.

"We will represent these three categories with the traffic light symbols green, amber and red."

The scheme will be voluntary and service providers and search engines will be able to decide how their users want to see the ratings displayed.

"At this stage a lot of it depends on how much the search engines buy into the scheme. We want to help them look after their sites, and if some of the big ones get involved, then they can make the age-rating option available for everything."

The crowdsource monitoring option would then allow users to judge the chosen rating and to spot abuses of the system. If there is a serious problem, such as an example of hate speech or of child abuse, it can be reported. In Britain the default reporting link will take users through to the Internet Watch Foundation hotline. The traffic light innovation online reflects parallel concerns about what has become the most complex and perhaps most important area of the BBFC's work on films destined for general release. While public interest frequently focuses on the reclassification struggles surrounding controversial titles such as The Exorcist or A Clockwork Orange, the more delicate job is deciding whether to rate a film U or PG, 12 or 15.

BBFC president Patrick Swaffer said recently that in Britain certain key elements mark a film out for concern in respect of children. Aside from explicit or obscene material, the board is careful not to allow sequences showing children climbing into fridges or washing machines. The potential for these "imitative techniques" sets off alarm bells that would be reflected in the questionnaire for online user-generated content.

Last month the government allowed the BBFC to classify a whole new range of commercial DVDs that had been exempt. The decision will close a legal loophole that allowed young people to buy sexually explicit and ultra-violent material without restriction. Some pop videos, sports titles and religious and educational DVDs and Blu-Ray discs were classed as exempt. As a result, erotic scenes in videos by performers such as Robbie Williams and Beyoncé and topless scenes in supposed exercise DVDS were being sold without age restrictions. Violent footage of cage fighting was also exempt because it was classed as sport.