Corey Breen developed a slurry alarm to warn of high levels of toxic gas.
Paul Donegan, who has worked with machinery for 40 years, designed a PTO sensor.
Lift arm assist creators Matthew O'Sullivan, Edward Daly and John O'Brien at this year's National Enterprise Awards.
A roofing safety bar developed by Sean Keogh and Darragh Canny aims to stop falls from roofs during work.
Shane Hagan and Daniel Doherty with their product Reel Easy.