Section 52.1483 - Malfunction regulations(a) The following regulations are disapproved because they would permit the exemption of sources from applicable emission limitations under certain situations and therefore they do not satisfy the enforcement imperatives of section 110 of the Clean Air Act.(1) Clark County District Board of Health (i) Previously approved on May 14, 1973 and deleted without replacement on August 27, 1981: Section 12 (Upset, Breakdown, or Scheduled Maintenance).(ii) Section 25, Rule 25.1, submitted by the Governor on July 24, 1979.(iii) Section 25, Rules 25.1-25.1.4, submitted by the Governor on November 17, 1981.(iv) Section 25, "Affirmative Defense for Excess Emissions Due to Malfunctions, Startup, and Shutdown," submitted by the Governor on September 1, 2010.49 FR 10259, Mar. 20, 1984, as amended at 69 FR 54019 , Sept. 7, 2004; 79 FR 13567 , Mar. 11, 2014