Opening a high-pressure appliance with under 200 lb, using post-1993 equipment. Evacuate to how many inches of mercury vacuum?

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  1. 0 inches (atmospheric pressure)
  2. 10 inches
  3. 15 inches

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References

  1. 40 CFR 82.156 Required practices (Cornell LII) www.law.cornell.edu/cfr/text/40/82.156 Checked 2026-10-10.
  2. 40 CFR 82.156 Required practices (Cornell LII) www.law.cornell.edu/cfr/text/40/82.156 Checked 2026-10-10.

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