From [1] for fair use on Australian Rail Tram and Bus Industry Union

1. This image is a low-resolution image of the logo of an organization.
2. This image does not limit the copyright holder's ability to profit from the original source, nor will it dilute the importance or recognition of the logo in connection with its organization.
3. This image enhances the article in which it's displayed, as it provides an immediate relevance to the reader more capably than the textual description alone.