The -W option splits a file into multiple streams. You can use this if your EPROM programmer cannot split files into different devices when programming.
hex -W2 app.hzx -Fhex
This splits the application file app.hzx into high and low bytes for a processor with a 16-bit bus. The bytes at even addresses are placed in the file app.hzx.0.hex and the bytes at odd addresses in the file app.hzx.1.hex.