Q: Are these [paragraphs] separate or can they be used together?

OSHA 1910.269(l)(8)(v)

(C)  Arc-rated protection is not necessary for the employee’s head when the employee is wearing head protection meeting § 1910.135 if the estimated incident energy is less than 9 cal/cm2 for exposures involving single-phase arcs in open air or 5 cal/cm2 for other exposures,

(E)  For exposures involving single-phase arcs in open air, the arc rating for the employee’s head and face protection may be 4 cal/cm2 less than the estimated incident energy.

For example, if we have estimated the incident energy at 12.99cal/cm2 for single-phase open air, then we reduce this value to 8.99 cal/cm2 from E above and thus no face shield is needed as long as the hardhat meets 1910.135 from C above.  Or is C derived from E?

A:

Don’t think that is the intention.  The idea behind both of these phrases is to keep from overburdening climbing line workers from having restrictive PPE when possible.  Paragraph E assumes you will be wearing a shield but allows you to avoid a HOOD rather than making the 9 cal cut-off be a 12 cal cut-off.

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