The World Health Organization publish air quality guidelines based on the latest scientific evidence of the impact of air pollutants on human health. For some air pollutants, there is no safe level of exposure, and, in these circumstances, the guidance suggests levels that represent an achievable minimum. These guidelines are intended as a starting point for national Governments to develop measures that reflect the local factors that are known to shape the impacts of air pollution. We are considering World Health Organization guideline levels for particulate matter. This will enable us to understand practical aspects of achieving air quality improvements and inform our future plans.

The current legal limits on air pollution are derived from the law of the European Union, and set a minimum acceptable standard. The need for rules at EU level reflects the fact that air pollution does not respect national borders and requires a concerted response at local, national and international levels. Whatever the outcome of the Brexit process, we are committed to ensuring our environmental protections are aligned to those at EU level, with absolutely no lowering of standards.

Delivering against these standards requires collaborative action across Government and society. Therefore, the responsibility for tackling air pollution is shared right across the Cabinet. I have been working with the Minister for Economy and Transport on actions to address nitrogen dioxide exceedance in five sites across our strategic motorway and trunk road network. I am pleased to announce that 50 mph speed limits will be in place on a permanent basis across all five sites by the middle of July. We will be enhancing communications around the reason for the speed restrictions and providing new permanent traffic sign layouts at all sites, so that the public is aware of the importance of these measures.

At the end of this month, I'm due to receive feasibility study reports from Cardiff and Caerphilly councils, outlining action that they will take to achieve legal limits for nitrogen dioxide in the shortest possible time frame. The plans will be independently assessed by a panel of experts next month, and I intend to make a final decision on the implementation of measures as soon as possible thereafter, based on the evidence and advice.

Achieving clean air means that, as a society, we must reduce our reliance on the private car and encourage walking, cycling and use of public transport. Welsh Government is investing heavily in creating active travel routes across Wales, with more than £30 million of investment under way and more planned for next year. Our ambition for all buses and taxis to be low or no carbon emissions by 2028 will ensure that increasing use of public transport can contribute to improving air quality, as well as moving us towards a low-carbon economy.

Tackling air quality requires changes to the planning system to prevent air quality issues before they arise. Following changes to strengthen requirements to address air quality considerations in the revised 'Planning Policy Wales', published last year, I am pleased that planning officials and my own are developing a new technical advisory note for planners and developers on air quality and soundscape, following a focused call for evidence later this year.

Having the best available evidence is essential so that we can maximise the positive impact of the measures we take to address air pollution. In April this year, I commissioned an extensive assessment of multi-pollutant and cross-sector emission reduction measures. This research will provide the most detailed assessment ever conducted of air quality across Wales. It will consider the full range of possible interventions and assess them on the basis of value for money. Crucially, it will assess the potential impact of those measures against the seven wellbeing goals from our Well-being of Future Generations (Wales) Act. This evidence will be used to inform our clean air plan for Wales. In turn, the plan will identify those areas that require the changes to legislation to be addressed through our clean air Act.

From our first breath to our last, we all need clean air to lead healthier and happier lives. The action I have described demonstrates Welsh Government’s commitment to delivering new infrastructure, evidence and regulation to help to achieve this aim. There is also action we can all take today to avert the dangers of air pollution. We can all reduce our personal contributions to air pollution and our exposure to it. That is why Welsh Government has partnered with Global Action Plan for the first time to celebrate Clean Air Day on 20 June. It is vital we inform everyone about the causes of air pollution and the role we each have in tackling it. So, I urge all Members of the National Assembly and everyone listening to this debate to support the Clean Air Day campaign and consider what you can do to ensure that Wales breathes clean air.