Regarding that front ring: I tried searching through the OSHA website and OSHA regs as best I could, but I found no reference to the requirement for a front ring, only that for fall arrest, the attachment goes in the back (as already noted).
I did find a discussion (see link) about a change in the ANSI harness specification (which I believe OSHA uses) and that discusses the front ring and its uses. (ANSI specs are available only at a cost, so I don't have the full citation.)
Lab Safety Supply - EZ Facts Safety Info - Document #347, ANSI Z359 - A New Lift to Fall Protection Standards
And part of that discussion:
Another change to Z359.1 was the addition of requirements and markings for harnesses equipped with a front-mounted D-Ring or attachment. In the past, standard harnesses with a front mounted D-ring could utilize that D-ring attach point for ladder climbing, fall restraint or work positioning systems only. “The new standard offers an explanation, that the front D-ring attachment on a harness should be positioned within the sternum (at the breastbone) area of the body. The front D-ring attachment is intended for the use in rescue, work position, rope access, and other ANSI Z359.1 recognized applications where the design of the systems is such that only a limited free fall of two (2) feet is permitted.”
Joe
I did find a discussion (see link) about a change in the ANSI harness specification (which I believe OSHA uses) and that discusses the front ring and its uses. (ANSI specs are available only at a cost, so I don't have the full citation.)
Lab Safety Supply - EZ Facts Safety Info - Document #347, ANSI Z359 - A New Lift to Fall Protection Standards
And part of that discussion:
Another change to Z359.1 was the addition of requirements and markings for harnesses equipped with a front-mounted D-Ring or attachment. In the past, standard harnesses with a front mounted D-ring could utilize that D-ring attach point for ladder climbing, fall restraint or work positioning systems only. “The new standard offers an explanation, that the front D-ring attachment on a harness should be positioned within the sternum (at the breastbone) area of the body. The front D-ring attachment is intended for the use in rescue, work position, rope access, and other ANSI Z359.1 recognized applications where the design of the systems is such that only a limited free fall of two (2) feet is permitted.”
Joe