A high-pressure appliance (for example, one using R-22) has a full charge of 250 pounds and is being recovered with equipment manufactured after November 15, 1993. To what level must it be evacuated before it is opened?
Not quite. The answer is C: 10 inches of mercury vacuum
Table 1 of § 82.156 splits high-pressure appliances at 200 lb of full charge: under 200 lb requires 0 in. Hg (0 psig) with newer equipment, while 200 lb or more requires 10 in. Hg. The 4 in. Hg figure is the level for 200-lb-plus high-pressure appliances when older (pre-November 1993) equipment is used, and 15 in. Hg is the newer-equipment level for medium-pressure appliances of 200 lb or more. Compressor status does not change these levels; it matters only for the percentage standard on small appliances.
Reference: 40 CFR Part 82 § 82.156(a), Table 1 (Required levels of evacuation)
Checked against the official text
Read the eCFR text current through 2026-10-30 of § 82.156. Table 1: high-pressure appliance with a full charge of 200 lb or more, using recovery equipment made on or after Nov. 15, 1993, must be evacuated to 10 in. Hg vacuum (under 200 lb: 0 in. Hg).