And provided further, That the levels of radiation from each electron tube containing byproduct material do not exceed 1 millirad per hour at 1 centimeter from any surface when measured through 7 milligrams per square centimeter of absorber.
For purposes of this paragraph "electron tubes" include spark gap tubes, power tubes, gas tubes including glow lamps, receiving tubes, microwave tubes, indicator tubes, pickup tubes, radiation detection tubes, and any other completely sealed tube that is designed to conduct or control electrical currents.
10 C.F.R. §30.15
For FEDERAL REGISTER citations affecting § 30.15 , see the List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume and at www.govinfo.gov.