I think you have a serious problem Mick,if mine was that high I would be giving a lot of thought into keeping as far away from my feathered friends as posible,or never be without a full face mask.I had my bloods tested at >> BRITISH PIGEON FANCIERS MEDICAL RESEARCH. Here is th email I recieved. Thank you for sending your blood sample to us for testing. The analysis of your blood has shown you have a level of reaction to pigeons of 19 mcg/ml This means that you have low sensitisation to pigeons. At this level, some people can develop mild symptoms. It is important to use a mask if there are chest difficulties, particularly when cleaning out the loft. This will usually control any pigeon lung problems. Further information and general advice can be found by visiting the website, www.pigeon-lung.co.uk Best Wishes, Kenneth Boyd Research Co-ordinator admin@pigeon-lung.co.uk I thought I had a problem,I don't know the high limit ??