Howard County, MD Noise from Specific Sources: HVAC & Mechanical Noise (2026)

Howard County Code § 8.900(d)(14) singles out air conditioning and heat pump equipment used to cool or heat housing on residential property for its own numeric standard, separate from the general noise table in COMAR 26.02.03.02B that governs most other sources under this ordinance. The rule reads: a person may not cause or permit noise levels which exceed 70 dBA for air-conditioning equipment at receiving residential property, and 75 dBA for heat pump equipment at receiving residential property. Because the limit is keyed to the 'receiving' property, the measurement point is the neighbor's property line, not the compressor itself, and the section does not distinguish between daytime and nighttime hours the way the general residential noise table does elsewhere in § 8.900.

The same section defines dBA by reference to COMAR 26.02.03.01 and requires that any sound level meter used to check compliance meet or exceed ANSI S1.4-1971 Type II specifications. Enforcement runs through § 8.900(e): a violation is a misdemeanor carrying a fine of up to $100.00, imprisonment of up to 30 days, or both. The Howard County Police Department may instead pursue a civil citation under Title 24 of the County Code, and the Health Department has independent civil-penalty authority when the offending noise originates from commercial or industrial property rather than a residence. A first civil violation is classified as a Class E offense; a second or later violation escalates to a Class D offense.