Platforms for roof work

We need to do some work on the chimney’s of a couple of historic structures.
The roof have 4/12 to 12/12 pitches depending on which building.
We need to purchase some kind of OSHA compliant work platforms to do the work, stock brick, etc.
Does anyone of recommendations or suggestions of manufacturers or sources.
Thanks, Jigs.
Replies
Jigs,
Got this from The Slateman (Walter) at BTC. He has some pics of setup there,
http://www.vanguardmanufacturing.com/products/CHIMNEY-BRACKET-FOR-ERECTION-OF-5%252dFT.-SCAFFOLD-FRAMES.html
KK
That's the best I've seen
That is the best unit I have seen. I'll try to order something next week.