Depth is the wrong question
It is the first thing people reach for and it decides nothing. Two identical cuts can land on opposite sides of the line depending only on how each was closed.
Where the line sits
The first aid list at 1904.7(b)(5)(ii) is a closed list — if a treatment is on it, it is first aid, and if it is not, it is medical treatment. Wound coverings and butterfly bandages or Steri-Strips are on it.
A note on older guidance
An OSHA letter of interpretation from 1998 addressed this question under the pre-2001 recordkeeping rule, and treated wound closure with Steri-Strips as medical treatment. The 2001 rule placed butterfly bandages and Steri-Strips on the first aid list. Where older guidance and the current rule text disagree, the rule text governs.
Safety Sherpa is software, not a safety consultancy. This page quotes the cited regulation and links to the source text so you can read it yourself. It is not legal advice and does not replace a qualified person's judgment about a genuinely unclear case — our tools walk you through the decisions the regulations require and record your reasoning. The determination is yours to make.
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