Arc Flash Simulation Training Trailer

My name is John Poole and I work for Great Southwestern Construction in Castle Rock, CO. My safety department needed a program to train hundreds of employees about NFPA 70E and Arc Flash dangers so I decided to build out a training trailer with 'traps' built into the system. I have most of the code written but I want to implement LED's and an alarm horn (5VDC) to simulate an actual arc blast when the trainees make a mistake. I'm relatively new to coding and programming and am seeking some ideas on how to perhaps improve the overall product and/or ensure the coding and subsequent wiring to each device and back to the shield and Arduino Mega. I can explain in greater detail if your interested...it would be best seen here at the office if you're relatively local. I have several more documents that I can send as well. Thanks in advance for your consideration...I really need the help!