In many cases the engine room is the original source for most of the noise problems generated in the marine environment. Therefore, there are a myriad of treatment methods employed to minimize the negative impact that this unwanted sound and vibration can have on your customers comfort.

First and foremost the engine room design should be considered. In understanding that sound energy travels through the air as a pressure wave, it becomes imperative that the engine room be designed so that there are minimum, if any, direct line of sight sound paths from the engine room to the occupied areas of the boat. All air paths should be tortuous and be treated with acoustical baffles; this includes unsealed hatches, air intakes, exhaust paths, and open hull conduits. Since sound energy can also be transmitted through the hull and other structural members it is also imperative that the engine room design allow for adequate isolation mounting of all mechanical components and other sources of vibration. Technicon can assist you at this design phase in order to ensure that appropriate acoustical design elements are considered prior to any construction. This is often the most economical way to avoid having a noise problem.

Once the design has been established several methods of acoustical treatment should be considered. Reverberation within the engine room will increase the overall noise levels. The proper sound absorber application will minimize reverberation. Absorber/Barrier composites should be used on all surfaces leading to occupied areas of the boat in order to minimize sound transmission from the engine room to the passenger areas. Where possible bulkheads and other structural members should be treated with vibration isolation materials in order to attenuate vibration leading to structure born noise. Exposed floors should be treated with acoustical matting designed for safety, comfort, and durability.

Examples:

Gasoline Powered Engine Room

Absorber Material - AF-022-40-AR-00
Absorber/Barrier Composite - VBFF-322-31-AR-00
Vibration Isolation Material - REGUFOAM™ 300
Acoustical Flooring - DP-600
 

Diesel Powered Engine Room

Absorber Material - AF-001-40-AR-00
Absorber/Barrier Composite - VBFF-301-31-AR-00
Vibration Isolation Material - REGUFOAM™ 300
Acoustical Flooring - DP-600
 

In many cases, despite exceptional work done to minimize engine room noise impact on the hull structure, the hull itself by the virtue of its contact with the external environment can be a major source of noise problems. Secondary engine or shaft vibration, propeller cavitation or even fluid dynamics can set up resonate modes in the hull that cause the entire boat to act as a giant sounding board or drum. The proper vibration damping materials applied strategically to the hull or deck can effectively dampen the resonate frequencies of the hull and minimize the noise problem and significantly improve passenger comfort. Again the proper installation of vibration isolation materials between structural members can disrupt the transmission of vibratory energy between surfaces and dramatically reduce noise problem for the passengers. Hull liners can be used to treat open cavities in the hull in order to reduce reverberation throughout open spaces in the structure.

Examples:

Propeller plane damping - DC-100
Hull Damping - DP-300 or DP-400
Vibration Isolation - REGUFOAM™ 300 or REGUFOAM™ 400
Hull Liner - PF-012-80-00-00

In the acoustical treatment of the occupied areas of the boat the comfort, convenience, aesthetics, and individual tastes of the owner must be a priority. Headliners and soft trim components can minimize echoes and improve the quality of the sound within the passenger compartments. Floor underlayments should be used to block sound transmission from underneath occupied areas and to dampen footfall noise. Technicon Industries offer a wide variety of colors and styles of marine headliners in both designer fabrics and vinyls. We also produce trim materials that can be vacuum-formed or thermo-formed to meet your demanding needs.

Examples:

Headliner - AF-025-10-XX-00 (XX=color to be determined)
Trim Panels - AF-060-10-XX-00 (XX=color to be determined)
Floor Underlayment - VBF-351-01-00-00
 

Fuel and water tanks can act as drums and radiate noise throughout the rest of the vessel. Proper damping materials can minimize this effect. Additionally the large surface areas of these tanks should be treated with acoustical absorbers in order to reduce reverberation in most cases. Ice boxes and bait boxes usually need the same type of treatment with the added consideration of thermal insulation for optimal performance.

Examples:

Fuel and water tanks - DF-301-40-AR-93
Ice and bait boxes - DP-312-80-AR-93
 

Generator sets have many of the same sound features as the main engine and should be analyzed for treatment in much the same way. Even if the generator set is already located within a treated engine room it may be necessary to further treat the genset. Many boat owners find the sound of the generator particularly bothersome because gensets typically run while at anchor and during other times of general quiet. Placing the genset in its own enclosure isolated from the hull structure and lined with the appropriate acoustical absorber or absorber/barrier composite is recommended.

Examples:

Small Generators - AF-022-40-UW-00
Large Generators - VBFF-322-31-UW-00
 

Bulkheads offer multiple opportunities to reduce reverberant noise, block sound transmission, isolate vibration, and improve sound quality based on their location in the boat's structure. Bulkheads adjacent to the engine room should be constructed with internal vibration isolation materials and faced with absorber/barrier composites facing the engine room. Bulkheads throughout the passenger compartments can be covered on the inside with aesthetic trim laminations to improve sound quality, and on the outside with acoustical absorbers to reduce reverberation.

Examples:

Engine room bulkheads

Internal vibration isolation - Regufoam™300
Side toward engine compartment - VBFF-322-31-AR-00
 



Passenger compartments

Internal - AF-025-10-XX-00
External - AF-025-40-UW-00, AF-025-40-XX-00