Teach Soap

I would like to create a liquid soap that men and women can use to get grease off their hands when they've been working in the shed. There is a comercial liquid soap here in Australia that does this and I'd like to make my own version, the comercial soap has scrubby bits and contains citrus oil. I have however noted that citrus oil can cause burns when exposed to the sun after using it. So I'd like any help on if I could use the citrus oils or is there something better for use on grease and oil? because plain soap just doesn't cut it.
Thanks