The lawful use of copyrighted works in the UK falls under the term 'fair dealing'. The following is a list of relevant instances of 'fair dealing' as outlined by the UK Intellectual Property Office :
The majority of the image usage for research done at SIA will be covered under fair dealing, but don't forget to properly reference the pieces. For more information, visit the library's Chicago referencing guide.
If you have concerns regarding copyrighted materials, one suggestion might be to use images which use Creative Commons licences. Licensing under Creative Commons allows content creators to determine how their work can be used and attributed. There are six types of Creative Commons licences which govern attribution, distribution, modification of a creator's work.
The Creative Commons also has a help service to assist in research across a number of search services.