exposure should be considered to exceed the limit value. Cn indicates the total time of
exposure at a specified noise level, and Tn indicates the total time of exposure
permitted at that level.
Exposure to impulsive or impact noise should not exceed 140 dB peak sound
18.104.22.168 Equipment Design Sound Levels. All equipment which produces noise as a side
effect of operation shall be specified for noise level not in excess of 84 dBA (A scale
rated sound pressure level referenced to 0.0002 microbar) when measured 5 feet above the
mounting floor level and 3 feet from the equipment base. Equipment which cannot meet
this specification shall be provided with appropriate silencers or enclosed as necessary
to contain or direct the emanating sound.
22.214.171.124 Space Design Sound Levels. Power plant areas which require air conditioning
usually require consideration of sound level also. These areas include central control
rooms, offices, and laboratories. The acoustical design goals for these areas is the
achievement of background sound levels which will not interfere with the occupancy
requirements. For complete information relative to design, control, and testing of
Engineers (ASHRAE) Handbooks, Fundamentals and Systems Volumes.
Handling of Toxic and Hazardous Substances
126.96.36.199 Hazard Communication Standard. OSHA standards for hazard communications are
presented in Title 29, CFR Part 1910, Subpart Z, paragraph 1910.1200.
188.8.131.52 Local Exhaust. For design guidance of local exhaust systems for mixing tanks,
local feed systems, test bench hoods, etc., see MIL-HDBK-1003/17 Industrial Ventilation
Systems, and ACGIH Industrial Ventilation Manual.
184.108.40.206 Storage. For design criteria pertaining to storing of all types of toxic and
hazardous substances, see MIL-HDBK-1032/2, Covered Storage.
Provide storage per manufacturer's recommendations or
220.127.116.11 Dry Chemicals.
18.104.22.168 Liquid Chemicals. Provide curbed area around liquid storage or mixing tanks
and chemical feed equipment. Volatile toxic chemicals will require special ventilation
as acids, morpholine, hydrazine, etc. For design criteria, refer to ACGIH Industrial
Subpart Z - Toxic and Hazardous Substances.