Noise and vibration on board ships affect crew health, passenger comfort, equipment reliability and contractual compliance. This in-depth professional course covers shipboard noise and vibration engineering from first principles to practical control. It explains acoustic levels and frequency bands, how levels are combined and rated, and how noise affects hearing and annoyance. It then examines the role of noise and vibration consultancy across the ship lifecycle, from specifications and early design decisions to trials and troubleshooting, together with IMO, offshore and class requirements. Prediction methods, from typical levels by ship type and source ranking to transfer functions, mobility and statistical energy analysis, lead into practical control measures for machinery, seatings, enclosures, HVAC and exhaust systems. The final part covers vibration sources and response, dynamics, resonance, shock and propeller-induced excitation.
Course at a glance: Duration 20 hours · Self-paced online · 9 sections, 45 lessons, a 197-page downloadable course book
What you will learn
- Apply source-path-receiver reasoning to diagnose shipboard noise problems.
- Combine and convert sound levels and interpret frequency bands, rating methods and hearing effects.
- Interpret shipboard noise criteria in IMO, offshore and class rules and their contractual significance.
- Predict noise at design stage using source strength, transfer paths, mobility and statistical energy analysis concepts.
- Select practical control measures, including resilient seatings, enclosures, cavity treatment and HVAC and exhaust silencing.
- Explain global and local vibration response, resonance, damping and shock.
- Describe propeller-induced excitation, cavitation and hull pressure pulses as vibration sources.
Inside the course: a high-level summary, section by section.
Acoustic fundamentals
The course begins with the language of acoustics. Sound pressure level is expressed in decibels because the ear responds to a vast range of pressures, and frequency bands, such as octaves and third-octaves, describe how sound energy is distributed across the spectrum. Because decibels are logarithmic, levels from several sources must be combined on an energy basis rather than simply added. A key practical consequence is that the dominant source controls the total: reducing it usually produces far more benefit than trimming several smaller contributors, so ranking sources should always come before choosing countermeasures.
Reduction principles, rating methods and the effects of noise on people complete the section. Weighted levels and rating curves reflect human sensitivity, while annoyance, speech interference and sleep disturbance shape accommodation criteria. Hearing effects range from gradual age-related loss to noise-induced hearing loss and acoustic trauma from extreme exposure. A levels worked example consolidates the calculations.
Consultancy, specifications and regulations
The second section looks at noise and vibration as a professional service across the ship lifecycle. Early specifications and design decisions have the greatest influence on the outcome, because the arrangement of machinery and accommodation, the choice of equipment and the structural layout are fixed early. Engineering support continues through detailed design, sea trials and, when problems occur, troubleshooting.
Occupants experience noise and vibration as a single comfort impression, so the two should be considered together. The course explains that a statement that a ship will comply with IMO or class requirements is a binding contractual commitment, not a loose promise, and reviews the structure of IMO noise limits, offshore installation criteria organised by work and accommodation areas and voluntary class comfort notations.
Noise prediction
Prediction starts with typical noise levels by ship type and the spectra and dominant sources that characterise them. Thrusters, for example, can dominate fore-ship cabin noise on dredgers, offshore support vessels and dynamic positioning ships, even where the background is mainly from air conditioning. A design-stage prediction strategy is then built from source strength, transfer through structure and air, and radiation into the receiving space, following a disciplined workflow in which every term has a role and the result is checked against the frequency range where accommodation noise is most troublesome.
Mobility and statistical energy analysis concepts are introduced for structure-borne transmission. Mobility describes how readily a structure moves when excited, which governs how much vibration power enters from a machine, while statistical energy analysis treats the ship as connected subsystems exchanging vibrational energy, which is useful at higher frequencies.
Practical noise control
The control hierarchy starts at the source with quieter machinery, then addresses the path and finally the receiver. Resilient seatings isolate machinery from the structure, but their benefit can be lost through short-circuits, such as rigid pipes, cables or ducts, and flanking paths that bypass the isolation. Enclosures and cavity treatment reduce airborne noise from machinery, HVAC and exhaust systems need silencers, duct design and attention to flow velocities, and measures in the engine control room and accommodation, such as floating floors and resiliently mounted linings, protect the most sensitive spaces.
Shipboard vibration
The vibration sections start with sources and strategy. Propellers, main engines, auxiliary machinery and waves excite the hull, and the design strategy is to avoid resonance by separating natural frequencies from excitation frequencies or by controlling excitation at source. Global hull girder response is distinguished from local response of decks, panels, masts and equipment. Verification uses measurement and finite element analysis to predict natural frequencies and forced response.
Dynamics principles are developed through the mass-spring-damper model, natural frequency and reduced or equivalent parameters, resonance and damping. Shock and spectral response are introduced for naval and offshore applications, where equipment must withstand sudden loads, and a natural frequency worked example applies the theory.
Hydrodynamic excitation
The final technical section explains why propellers are often the most important excitation source. As blades pass through the non-uniform wake behind the hull, they generate pressure fluctuations at blade-passing frequency and its harmonics. Cavitation greatly amplifies hull pressure pulses and adds broadband noise. Design factors such as wake uniformity, tip clearance, blade number, skew and propeller loading strongly influence excitation levels. Because these choices are fixed early, close cooperation between hull designers, propeller designers and noise specialists at the concept stage is the most effective way to avoid excessive aft-ship vibration and noise in service.
Why this matters in practice
Noise and vibration problems discovered at sea trials are expensive and sometimes impossible to fix fully, and they can lead to contractual penalties, loss of class comfort notations or unhappy crews and passengers. Engineers who understand the full chain from specification to prediction, control and verification can protect a project from these risks and solve problems efficiently when they do arise.
Key takeaways
You leave able to apply source-path-receiver reasoning, combine and rate noise levels, interpret regulations and contractual criteria, predict and control shipboard noise, analyse vibration response and resonance and understand propeller-induced excitation.
How you study
The course is delivered fully online and is self-paced, so you can fit roughly 20 hours of study around professional commitments. Lessons combine clear explanation with examples, diagrams and short interactive checks, and the main sections end with graded quizzes (7 in total) so you can confirm you can apply each method before moving on. A 197-page course book can be downloaded and printed for offline reading and later reference.
Course contents
- Fundamentals of Shipboard Noise Control: Source, Path and Receiver; Levels and Frequency Bands; Combining and Converting Levels; Reduction Principles; Rating, Annoyance and Hearing; Section 1 Practice Problems
- Acoustic Design Process and Regulations: Consultancy Across the Lifecycle; Specifications and Early Decisions; Engineering, Trials and Troubleshooting; IMO, Offshore and Class Rules; Section 2 Practice Problems
- Representative Noise Levels and Prediction Methods: Typical Levels by Ship Type; Spectra and Dominant Sources; Design-Stage Prediction Strategy; Source Strength and Transfer; Mobility and SEA Concepts; Section 3 Practice Problems
- Practical Noise Control Measures: Machinery Control Hierarchy; Seatings, Short-Circuits and Flanking; Enclosures and Cavity Treatment; HVAC and Exhaust Control; ECR and Accommodation Measures; Section 4 Practice Problems
- Shipboard Vibration Fundamentals: Vibration Sources and Strategy; Global and Local Response; Verification and FE Analysis; Section 5 Practice Problems
- Dynamics, Vibration and Shock Principles: Mass-Spring-Damper Model; Natural Frequency and Reduced Terms; Resonance and Damping; Shock and Spectral Response; Section 6 Practice Problems
- Hydrodynamic Excitation Forces: Propellers as Excitation Sources; Cavitation and Hull Pressure; Design Factors and Key Terms; Section 7 Practice Problems
- Summary: Key Takeaways
Who this course is for
This course is for engineering graduates and practising engineers in naval architecture, marine engineering, acoustics and ship design who specify, predict, measure or troubleshoot noise and vibration on ships and offshore installations. It also suits owners’ representatives and surveyors who review noise and vibration requirements. A background in basic dynamics is helpful.
Frequently asked questions
How long does Onboard Noise and Vibration take?
The course is designed for about 20 hours of study. It is self-paced and fully online, so you can spread it over a few weeks or complete it more quickly.
What is covered?
The course is organised into 9 sections with 45 lessons, moving from foundations to applied methods, as summarised above.
Is there material to keep after the course?
Yes. A downloadable 197-page course book accompanies the lessons for offline reading and later reference.
How is progress checked?
Each main section closes with a graded quiz (7 in total). The quizzes test understanding of the concepts and methods explained in the lessons rather than memorisation, and you can review the relevant lessons before attempting them.
Can I record this study for my own professional development?
Yes. The course notebook includes a self-assessment of the course objectives before and after study, a reflection page and a learning log, which you can use to keep your own record of professional development.
Duration: 20 hours
Related courses: A06 – Ship Vibration and Noise; B04 – Marine Propulsion Systems and Thruster Design; B09 – Design of Auxiliary Systems (Extended Edition); B03 – Electrical Networks and Machines for Marine Applications
Enrol
Study at your own pace and work through the full course material, worked examples and section quizzes. Enrol in B10 – Onboard Noise and Vibration →
Recent Comments