Use of Air Purifiers to Improve Respiratory Health in Children

The goal of this pilot study is to investigate if installing an air purifier in the homes of children and young people with asthma improves their asthma outcomes. The main questions it aims to answer are: * Does installing an air purifier in the homes of children and young people with asthma improve their asthma outcomes * Is the use of an air purifier in the home acceptable to children and young people and their families? Children and young people with asthma attending our clinic will be selected at random to be invited to take part. For those that take part, an air purifier (Rensair Ltd. - Rensair Compact) will be installed in their home for a one-year period. Data will be collected on numbers of asthma attacks, rescue oral steroids, quality of life, symptoms, lung function at the beginning and at three-monthly intervals throughout the study period. The acceptability to children and young people and their families taking part in this study of using an air purifier in their home will also be assessed.