kennyjulie1 - Read the attached website and look at Incidental duties. It explains it okay, but you would need further advice from HMRC to make sure. Don't be fooled into not counting those days and then at the end of the year for the HMRC not to allow them and for you to be over your 91 day limit and therefore liable for tax.
http://www.hmrc.gov.uk/pdfs/ir20.pdf
Incidental duties
5.7 Whether duties you perform in the UK are 'incidental' to your overseas duties (paragraph 5.5) depends on all the circumstances. If the work you do in the UK is of the same kind as, or of similar importance to, the work that you do abroad, it will not be merely incidental unless it can be shown to be ancillary or subordinate to that work. It is normally the nature of the duties performed in the UK rather than the amount of time spent on them that is important, but if the total time you spend working in the UK is more than 91 days in a year, the work will not be treated as incidental. Examples of duties which we do not normally regard as incidental are
- attendance at directors' meetings in the UK by a director of the company who normally works abroad
- visits to the UK as a member of the crew of a ship or aircraft
- visits to the UK in the course of work by a courier.
5.8 If the work you do in the UK has no importance in itself, but simply enables you to do your normal work abroad, it may be treated as incidental. We will decide after looking at all the circumstances in your case. Examples of duties which we regard as incidental are
- visits to the UK by an overseas representative of a UK employer to report to the employer or to receive fresh instructions
- training in the UK by an overseas employee as long as - the total time spent in the UK for training is not more than 91 days in a year, and
- no productive work is done in the UK in that time.