Reduce marine noise and vibration on vessels

Get help throughout planning, building and operation

• Before you start building

  Define noise and vibration comfort criteria at the beginning of a new shipbuilding project. It is much easier to agree on comfort criteria and install reasonable noise and vibration mitigating measures during the project than to rectify issues after the ship is built and delivered.

  We can help ensure that your ship's noise and vibration comfort criteria meet expectations. We know the requirements of the International Maritime Organisation, IMO, and classification society's requirements/criteria and have vast experience measuring noise and vibration levels.

  In this phase we help you:

  • Draft the building specifications for your ship regarding noise and vibration requirements
  • Negotiate building specifications between yard and shipowner
  • Understand and safeguard the expectations of the owner
  • Ensure the yard understands the consequences of noise requirements regarding noise and vibration mitigating measures and impact on the project

  Which criteria to use for noise and vibration?

  The International Maritime Organization (IMO) has a set of requirements in resolution MSC. 337(91) "Code on Noise Levels on Board Ships", which aim to secure acceptable working conditions for the crew. However, in many cases, the requirements are too relaxed, especially when it comes to passenger comfort.
  
  Major classification societies such as Lloyd's Register, DNV and ABS have non-mandatory requirements for passengers and crew that can be applied to different types of ships. The requirement can be further divided into categories depending on your ambition regarding noise and vibration comfort.  We assist in defining specific noise and vibration requirements for your project based on experience.
  
  

• When you design your ship

  Designing a new ship is a complex task that requires you to plan sufficient noise and vibration-reducing measures to meet requirements.

  In this phase, we assist you in validating, reviewing and providing input for:

  • insulation plan drawings
  • general arrangement drawings
  • structural drawings
  • machinery drawings
  • machinery vibration isolation systems etc.

  Predicting noise and vibration levels

  We can calculate the expected noise and vibration levels in different areas of your ship. Our analytical tools help minimise the risk of noise and vibration issues after the vessel is built and support the yard and owner in understanding the impact of noise and vibration for different mitigating measures as the project progresses.

  We use tools such as Finite Element Analysis (FEA), Computational Fluid Dynamics (CFD) and ray tracing acoustics to predict:

  • noise and vibration levels internally on the ship
  • environmental noise from the ship
  • acoustic performance of different constructions
  • measures to minimize machinery noise and optimize vibration performance
• When building your ship

  It is essential to know the machinery's actual acoustic properties, performance, and individual building components before installing noise and vibration-reducing measures.

  We can perform an acoustical benchmarking test for your building components, like floating floors, windows, doors and bulkheads. The tests help you determine optimal features for your ship. At our acoustics laboratory facilities, we test the building components you have in mind for:

  • sound insulation
  • impact noise reduction
  • acoustic absorption
  • apparent dynamic stiffness
  • sound pressure level / velocity insertion loss and the radiation index.

  We can also test machinery noise and vibration to determine the sound power levels of various products. You can use these measurements as documentation for product properties and performance.

  All our laboratory tests can be performed accredited or as guiding information.

  We participate and assist during factory acceptance of major machinery for pre-checking that requirements are met and provide consultancy for further improvement.

  We also perform structural and sound insulation tests during the building phase to ensure analytical calculations comply with what is measured and verify structural and building component properties at a relatively early stage of the project.

• Completing the ship

  Once your ship is due for sea and harbour acceptance tests, we can help you measure your noise and vibration levels per the agreed measurement standards, operating conditions and comfort criteria. We can assist in authoring protocols before measurements. 
  
  Qualified personnel must perform the measurement to document agreement with the building specification.  
   
  
  If the results indicate that the ship's acoustics and vibration levels do not comply with requirements, we perform troubleshooting measurements to advise on possible corrective actions. 
  
  We perform in-field noise and vibration measurements during factory, harbour, and sea acceptance tests. Our noise and vibration measurements can be performed accredited. We also help you prepare noise and vibration protocols before the acceptance test. 
  
  We perform measurements following relevant standards like:

  • Multi-channel noise and vibration measurements
  • Sound pressure level measurements
  • Vibration measurements
  • Sound insulation measurements
  • Impact noise measurements
  • Structural vibration testing, mobility, natural frequency, damping, operational deflection shapes etc.
  • Sound intensity measurements
  • Sound Power measurements
  • Order tracking measurements
  • Environmental noise measurements

  FORCE Technology is authorised by the Danish Maritime Authority to perform noise measurements on ships.
  
  

• Noise and vibration troubleshooting at sea

  Noise and vibration issues might appear when the ship is in operation. In this case, we can help you understand an adverse noise and vibration problem and detect the source of origin.

  Our vast experience with noise and vibration-related issues from other ships and our state-of-the-art measurement equipment is a sound basis for providing troubleshooting measurement assistance that can help solve your acoustics issues.

  Your expert on noise measurement standards

  Rules, standards and regulations change continuously. We know when and how. We participate in ISO committees and have been selected as the reference laboratory for noise measurements for the Danish Environmental Agency. Our engagement in standardisation puts us at the forefront of developing measurement standards. It lets us impact how rules, standards and regulations change for the benefit of our clients.