Directory access rights or file rights

Here is the problem, I have a directory on a Novell 5.1 server that everyone uses to store all kinds of files (ie.. graphics,pdf,video clips, music …etc).
I want to keep the directory for storage so that users can copy files to and from the directory but I don’t want users to be able to execute any of the files within the directory. What rights do I use to make these file non-excutable when they are copyied back and forth from the server directory to pc’s and vice versa.
In unix I know how to do this but in novell I’m not sure how to set this up.