Handheld device for remote asthma patient monitoring in children or adults. Accurate electronic respiratory monitor suitable for home use and for both children and adults. Electronic records which eliminates the need for paper record cards. Measures FEV1, FEV0.5, FEV0.75 and PEF. Displays percentage of personal best FEV1. Sets 'personal best' zones for test subjects. Quality of blow indicator. 600-test memory. Suitable for use in clinic with Bacterial Viral Filters (BVF). Large, easy-to-read display.