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Rules for Classification and Construction

I Ship Technology

1 Seagoing Ships

18 Harmony Class Rules on Rating Noise and Vibration for Comfort,Cruise Ships (v >25 kn)

Edition 2004


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The following Rules come into force on June 21th

, 2004.

"General Terms and Conditions" of the respective latest edition will be applicable

(see Rules for Classification and Construction, I Ship Technology, Part 0 Classification and Surveys).

Reproduction by printing or photostatic means is only permissible with the consent of Germanischer Lloyd.

Germanischer Lloyd AG

Head Office Hamburg

Vorsetzen 35, D-20459 Hamburg

Telefon +49 40 3 61 49-0

Telefax +49 40 3 61 49-2 00

[email protected]

http://www.gl-group.com

Published by: Germanischer Lloyd AG, Hamburg Printed by: Gebrder Braasch GmbH, Hamburg
http://www.gl-group.com/


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Table of Contents

Section 1 Classification

A. Scope ......................................................... ............................................................... .................. 1- 1

B. Harmony Criteria Numbers (hc) ...................................................... ........................................... 1- 1

C. Class Notation ................................................................ ............................................................ . 1- 1

Section 2 Required Noise and Vibration Limits

A. General ................................................................... ........................................................... .......... 2- 1

C. Vibration Requirements ..................................................................... ......................................... 2- 1

Section 3 Required MeasurementsA. General ................................................................... ........................................................... .......... 3- 1

B. Measuring Conditions ................................................................ ................................................. 3- 1

C. Performance of Measurements ................................................................... ................................. 3- 2

D. Survey Programmes ................................................................. ................................................... 3- 7

E. Survey Report ............................................................. ....................................................... ......... 3- 7

Section 4 Calculation Procedure ofhcClass_Notation

A. Determination of single hc .............................................................. ............................................ 4- 1

B. Averaging of single hc .................................................................................................. .............. 4- 1

C. Determination ofhcClass_Notation ....................................................... ......................................... 4- 2

Annex A Standards

A. General ................................................................... ............................................................. ........ A- 1

B. Standards ................................................................ ............................................................ ........ A- 1

Annex B Definitions

A. Important Definitions .................................................................. ................................................ B- 1

Annex C Recommendations to Reduce Noise and Vibration

A. General ................................................................... ............................................................. ........ C- 1

B. Considerations Regarding Excitation Forces .............................................................................. C- 1

C. Theoretical Investigations ............................................................................ ............................... C- 1

D. Secondary Measures .................................................................. ................................................. C- 2

E. Supplementary Measurements during Production Phase ............................................................ C- 2

Annex D Protocol Sheet

A. Measurement Protocol Sheet ............................................................... ....................................... D- 1

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Section 1

Classification

A. Scope

1. In general, these Rules are based on nationaland international standards listed in Annex A. Theywill be adapted to the latest editions of these standardswhen deemed necessary or will be modified to ac-count for the progress of knowledge. The Rules reflectthe state of the art in vibration and acoustic technol-ogy.

2. Some important definitions for expressionsused in these Rules are given in Annex B.

3. Among various comfort-promoting factors(e.g. decor and furniture of cabins and public spaces,indoor climate, board service, ship motions etc.), twomain parameters determining the comfort on board a

passenger ship are dealt with in these Rules: noise andvibration.

4. In this context, noise and vibration are de-fined as follows:

Noise:

Audible air pressure variations, generated forinstance by main engines, propellers, auxiliarymachinery, systems and persons within the fre-quency range of 16 to 16 000 Hz.

Vibration:

Structural oscillations in the frequency range of1 to 80 Hz

5. The influence of ship motions (seasickness)

on human well-being is not considered in these Rules.

6. These Rules are intended to support ownersand shipyards to specify requirements regarding com-fort for passengers and crew on board seagoing cruiseships.

7. Requirements according to current regula-tions of the responsible flag state regarding maximumnoise and vibration levels in crew spaces have to befulfilled independently of these Rules.

8. If the maximum speed of the passenger shipis equal or less than 25 knots, the requirements de-fined for cruise vessels < 25 knots must be applied.

9. If the maximum speed of the passenger ship

exceeds v = 7,16 1/6

[knots], the requirementsdefined for high speed craft have to be applied.

10. If the length between perpendiculars is lessthan 80 m, limit values given in these Rules do notapply. They shall be agreed upon separately afterconferring with Germanischer Lloyd (GL).

B. Harmony Criteria Numbers (hc)

To allow for a graduation of noise and vibration lev-els, 5 harmony criteria numbers (hc) are introduced:

hc = E = excellent comfort

hc = 1 = very high comfort

hc = 2 = high comfort

hc = 3 = moderate comfort

hc = 4 = acceptable comfort

Two separate numbers, hcpass and hccrew, reflect the

level attained for passenger and crew spaces, respec-tively.

1. Respective limit values of noise and vibrationare defined in Section 2.

2. Compliance with criteria given in these Rulesshall be verified through measurements performedunder defined conditions at specified locations; seeSection 3.

C. Class Notation

1. Upon request, ships complying with theseRules are granted the following special Notation ofHarmony Class

( )pass crewHC hc /hc

For instance, HC (2/3) corresponds to a high comfortfor passengers and a moderate comfort for crew, ac-cording to B.

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2. For a series of ships, the required noise meas-urements have to be conducted individually for eachship of the series. Regarding vibration measurements,a reduced measurement programme can be acceptedfor sister ships.

3. After modifications (e.g. conversions) thatmight influence the noise and vibration behaviour, theclass notation has to be reconfirmed by GermanischerLloyd.

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Section 2

Required Noise and Vibration Limits

A. General

1. Requirements given in these Rules refer tohuman well-being only. However, to achieve a cer-tain level of noise and vibration comfort, it must beensured that main and auxiliary machinery do notvibrate heavily. Therefore, limit values given in cor-responding standards or Classification Rules, forinstance Part 1 Seagoing Ships, Chapter 2 Machinery Installations, Section 2, Fig. 2.1, shall be

observed, too.

2. Requirements regarding acoustic privacy aregiven in addition to those for noise and vibration.

3. Requirements for noise and vibration arepresented for three operating conditions:

sea mode

harbour operation

thruster operation

The noise and vibration limits given for sea modeoperation form an upper bound for any operationmode at typical ship speeds.

4. Requirements regarding measurements forthe three operating conditions are given in Section 3,B.

5. Limits are given separately for passengerand crew spaces.

6. Requirements are related to different imis-sion zones as defined by frame A, B, C and D. The

principal arrangement of these zones is shown in Fig.

2.1 for a typical fast passenger vessel, see also "Imis-sion zones" in Annex B.

B. Noise Requirements

1. Most relevant standards are ISO 2923, ISO717/1 and ISO 717/2.

2. Required noise limit values depending onthe harmony criteria number (hc) are listed in Tables2.1to 2.4.

3. The measurement procedure and the calcula-tion of the hc achieved by noise measurements aredescribed in Section 3, C.and Section 4, respectively.

C. Vibration Requirements

1. The most relevant vibration standard is ISO

6954, edition 2000-12-15. The limit values refer,consequently, to the overall frequency-weighted rmsvalue in the range of 1 to 80 Hz. The vibration veloci-ties are given in mm/s.

2. Required vibration limit values dependingon the harmony criteria number (hc) are listed inTables 2.5and 2.6.

3. The measurement procedure and the calcula-tion of the hc achieved by vibration measurementsare described in Section 3, C.and Section 4, respec-tively.

aft bulkhead

of bow thruster

room0,15 Lpp

CBA D

20 m

Fig. 2.1 Imission zones

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Table 2.1 Noise limits, passenger spaces

Sea Mode 1, 2Harbour

Operation 1, 2

Thruster

Operation 2 , 3, 4

hc hc hcNoise level limits [dB(A)]E 1 2 3 4 E 1 2 3 4 E 1 2 3 4

Indoor spaces aft of frame A

First-class cabins 50 52 54 56 58 44 46 48 50 52 52 54 56 58 60

Standard cabins 54 56 58 60 60 46 48 50 52 54 56 58 60 62 64

Public spaces, type 1 and 2 56 58 60 62 64 52 54 56 58 60 60 62 64 66 68

Corridors, staircases 58 60 62 64 64 54 56 58 60 62

Indoor spaces between frame A and C

First-class cabins 46 48 50 52 54 44 46 48 50 52 52

54 56 58 60

Standard cabins 50 52 54 56 58 46 48 50 52 54 54 56 58 60 62



Indoor spaces between frame C and D

First-class cabins 44 46 48 50 52 44 46 48 50 52 52

54 56 58 60

Standard cabins 48 50 52 54 56 46 48 50 52 54 54 56 58 60 62



Indoor spaces forward of frame D

First-class cabins 44 46 48 50 52 44 46 48 50 52 52 54 56 58 60

Standard cabins 46 48 50 52 54 46 48 50 52 54 56 58 60 62 64



Outdoor spaces

Open deck recreation areas 64 66 68 70 75 64 66 68 70 72 64 66 68 70 72

Exhaust/supply air openings in open deck

recreation areas5 68 70 72 75 80 68 70 72 75 80 68 70 72 75 80

1 In each space the noise level generated only by air-conditioning and mechanical ventilation systems must be at least 4 dB(A) below the

required noise limit value for harbour operation.2 In each sanitary cell the noise level generated only by air-conditioning exhaust air systems at full capacity must not be more than 5

dB(A) above the required noise limit value for harbour operation.3 To be verified by measurements in the vicinity of thrusters only. Passenger indoor spaces aft of Frame A shall be considered during stern

thruster operation only. All thrusters running at not less than 70 % of full load. The noise limits shall be maintained also in standby

operation of thrusters.

4 Limit values valid, provided that thrusters are in operation for a maximum of 4 hours out of 24 hours.5 At a distance of 1,5 m.

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Table 2.2 Noise limits for acoustic privacy, passenger spaces

On board acoustic privacy sound insulation

(minimum requiredweighted apparent sound insulation index [dB]according to ISO 717/1 and ISO 140/4)

hcArrangements:

E 1 2 3 4

First-class cabins to first-class cabins (incl. bath to bath) 42 40 38 36 34

First-class cabins to standard cabins (incl. bath to bath) 42 40 38 36 34

Standard cabins to standard cabins (incl. bath to bath) 40 38 36 34 32

First-class cabins to corridors 40 38 36 34 32

Standard cabins to corridors 38 36 34 32 30

Pax cabins to crew spaces 50 48 46 44 42

Pax cabins to public spaces type 1 64 62 60 58 56

Pax cabins to public spaces type 2 58 56 54 52 50

Pax cabins to staircases 1

58 56 54 52 50

Pax cabins to engine room casings, elevator casings etc. 2 60 58 56 54 52

Pax cabins to HVAC rooms 3

58 56 54 52 50

Pax cabins to engine rooms 4

64 62 60 58 56

On board acoustic privacy impact sound insulation

(maximum permissible normalized sound pressure level index [dB]according to ISO 717/2 and ISO 140/7)

hcArrangements:

E 1 2 3 4

Pax cabins adjacent to pax cabins (soft floor) 46 48 50 52 54

Pax cabins adjacent to corridors (soft floor) 46 48 50 52 54

Pax cabins adjacent to crew spaces 46 48 50 52 54

Pax cabins adjacent to public spaces type 1 (soft, hard floors) 46 48 50 52 54

Pax cabins adjacent to public spaces of type 2 (hard floor) 48 50 52 54 56

Pax cabins adjacent to public spaces of type 2 (soft floor) 46 48 50 52 54

Pax cabins adjacent to open deck recreation areas (hard floor) 50 52 54 56 58

Pax cabins adjacent to jogging paths, dance floors etc. 5 5 5 54 56

Pax cabins adjacent to service spaces (galleys, pantries etc.) 46 48 50 52 54

1 In general, the number of passenger cabins located adjacent to staircases have to be minimized.2 Number of passenger cabins located adjacent to engine rooms and elevator casings etc. should be minimized. If possible, acoustic

buffer zones (e.g., service stores, lockers etc.) should be arranged between cabins and casings. The average sound pressure level in

engine room casings must be limited to max. 100 dB(A).3 Average sound pressure level in HVAC rooms located adjacent to passenger cabins must be limited to max. 80 dB(A).4 Arrangement of passenger cabins adjacent to engine rooms should be avoided. Otherwise specific provisions are required to achieve

limit values.

5 Arrangement of passenger and crew cabins below sport courts etc. should be avoided. However, if so arranged the on board impact

sound insulation index for sport courts etc. must be agreed upon between owner, yard and Germanischer Lloyd.

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Table 2.3 Noise limits, crew spaces

Sea Mode 1Harbour

Operation 1

Thruster

Operation 2, 3

hc hc hcNoise level limits [dB(A)]

E 1 2 3 4 E 1 2 3 4 E 1 2 3 4

Work spaces

Machinery spaces (not continuously manned) 5 110 110 110 110 110 110 110 110 110 110 110 110 110 110 110

Engine control rooms 69 71 73 75 75 64 66 68 70 72 67 69 71 73 75

Workshops 80 85 85 85 85 80 80 80 80 80

Open deck working areas 4

75 75 80 85 85 75 75 80 80 85 75 75 80 80 85

Stores 5 80 85 90 90 90 75 75 80 85 85

Indoor spaces not specified 5 90 90 90 90 90 90 90 90 90 90

Service spaces

Galleys 6

68 70 72 75 75 66 68 70 75 75 68 70 72 75 75

Serveries, pantries 6 66 68 70 75 75 66 68 70 75 75 66 68 70 75 75

Navigation spaces

Navigation bridge and chart rooms 55 55 60 60 65 55 55 60 60 65 58 58 60 60 65

Radio rooms 55 55 60 60 60 55 55 60 60 60 55 55 60 60 60

Listing posts, including outdoor bridge wings 7

65 65 70 70 70 65 65 65 70 70 65 65 70 70 70

Accommodation spaces

Day and sleeping rooms / officers 50 52 54 56 58 50 52 54 56 58 62 64 66 68 70

Day and sleeping rooms / others 54 56 58 60 60 52 54 56 58 60 64 66 68 70 72

Mess rooms, offices, recreation rooms 59 61 63 65 65 57 59 61 63 65 66 68 70 72 74

Hospitals 54 56 58 60 60 54 56 58 60 60 64 66 68 70 72

Gymnasiums, treatment rooms 57 59 61 63 65 57 59 61 63 65

Corridors adjacent to cabins 58 60 62 64 66 56 58 60 62 64

Open deck recreation areas 68 70 72 75 75 68 70 72 75 75

1 In each space the noise level generated only by air-conditioning and mechanical ventilation systems must be limited to at least 4 dB(A)

below the required noise limit value for harbour operation (excluding work spaces and open recreation areas).

2 To be verified by measurements in the vicinity of thrusters only. All thrusters running at not less than 70 % of full load. The noise limitsare also to be maintained in standby operation of the thrusters.

3 Limit values valid provided that thrusters are in operation for a maximum of 4 hours out of 24 hours.

4 Spaces requiring verbal communication when berthing the ship (maximum 4 hours out of 24 hours).

5 Reference is made to IMO Resolution A.468 (XII) ear protectors should be worn when the noise level is above 85 dB(A).

6 With mechanical ventilation in normal operation.

7 Reference is made to IMO Resolution A.468 (XII) which also requires that the noise level at speed does not exceed 68 dB in the1/1 octave band at 250 Hz and does not exceed 63 dB in the 1/1 octave band at 500 Hz.

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Table 2.4 Noise limits for acoustic privacy, crew spaces

On board acoustic privacy sound insulation

(minimum requiredweighted apparent sound insulation index [dB]according to ISO 717/1 and ISO 140/4)

hcArrangements:

E 1 2 3 4

Cabins to cabins 40 38 36 34 32

Cabins to corridors 38 36 34 32 30

Cabins to stairways 56 54 52 50 48

Cabins to engine room casings, elevator casings etc. 1 58 56 54 52 50

Cabins to mess rooms, hospitals, gymnasiums, service spaces etc. 58 56 54 52 50

Cabins to engine rooms 2 60 58 56 54 52

1

The number of cabins located adjacent to engine rooms and elevator casings etc. should be minimized. If possible, acoustic bufferzones (e.g., corridors, service stores, lockers etc.) should be arranged between cabins and casings. The average sound pressure level inengine room casings shall be limited to max. 100 dB(A).

2 The arrangement of cabins adjacent to engine rooms should be avoided. Otherwise specific provisions are required to achieve limit

values.

On board acoustic privacy impact sound insulation

(maximum permissible normalized sound pressure level [dB]according to ISO 717/2 and ISO 140/7)

hcArrangements:

E 1 2 3 4

Cabins adjacent to cabins 52 54 56 58 60Cabins adjacent to dance floors, stages etc. 50 52 54 56 58

Cabins adjacent to gymnasiums 52 54 56 58 60

Cabins adjacent to service spaces (e.g. galleys, pantries etc.) 52 54 56 58 60

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Table 2.5 Vibration limits, passenger spaces

Sea ModeHarbour

Operation

Thruster

Operation 1

hc hc hc

Vibration limits [mm/s](overall frequency weighted rms

value 1 to 80 Hz)E 1 2 3 4 E 1 2 3 4 E 1 2 3 4

Indoor spaces aft of frame B

First-class cabins 1.4 1.8 2.2 2.6 3.0 1.6 2.0 2.4 2.8 3.2

Standard cabins 2.0 2.4 2.8 3.2 3.2 2.0 2.4 2.8 3.2 3.6

Public spaces, short exposure time 2.8 3.2 3.6 4.0 4.4

Public spaces, long exposure time 2.0 2.4 2.8 3.2 3.6

Corridors, staircases

Indoor spaces forward of frame B

First-class cabins 1.2 1.6 2.0 2.4 2.8 1.6 2.0 2.4 2.8 3.2

Standard cabins 1.6 2.0 2.4 2.8 3.2 2.0 2.4 2.8 3.2 3.6

Public spaces, short exposure time 2.4 2.8 3.2 3.6 4.0

Public spaces, long exposure time 1.8 2.2 2.6 3.0 3.4

Corridors, staircases

Outdoor spaces aft of frame B

Open deck recreation areas 2.6 3.0 3.4 3.8 4.2

Open deck recreation areas of overhangs 3.0 3.5 4.0 4.5 5.0

Outdoor spaces forward of frame B


Open deck recreation areas of overhangs 2.6 3.0 3.4 3.8 4.2

1 Thrusters operating at not less than 70 % of full load.

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Table 2.6 Vibration limits, crew spaces

Sea ModeHarbour

Operation

Thruster

Operation 1

hc hc hc

Vibration level limits [mm/s](overall frequency weighted rms

value 1 to 80 Hz)E 1 2 3 4 E 1 2 3 4 E 1 2 3 4

Work spaces

Machinery spaces (not continuously manned) 4.8 5.2 5.6 6.0 6.0

Engine control rooms 2.8 3.2 3.6 4.0 4.0

Workshops 3.6 4.0 4.4 4.8 4.8

Stores 4.8 5.2 5.6 6.0 6.0

Indoor spaces not specified 4.8 5.2 5.6 6.0 6.0

Service spaces

Galleys 2.5 3.0 3.5 4.0 4.0

Serveries and pantries 2.8 3.2 3.6 4.0 4.0

Navigation spaces

Navigation bridges and chart rooms 2.5 3.0 3.5 4.0 4.0

Radio rooms 2.5 3.0 3.5 4.0 4.0

Listing posts including navigation bridge wings 3.2 3.6 4.0 4.4 4.8

Accommodation spaces

Day and sleeping rooms / officers 1.7 2.2 2.7 3.2 3.2 2.0 2.5 3.0 3.5 4.0

Day and sleeping rooms / others 2.0 2.4 2.8 3.2 3.6

Mess rooms, offices, recreation rooms 2.4 2.8 3.2 3.6 3.6

Hospitals 1.7 2.2 2.7 3.2 3.2

Gymnasiums, treatment rooms 2.4 2.8 3.2 3.6 3.6

Corridors adjacent to cabins


1 Thrusters operating at not less than 70 % of full load

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Section 3

Required Measurements

A. General

1. Noise and vibration measurements and theirevaluation shall be carried out by experienced techni-cians employed by a company authorized by GL. Ifdesired, GL will conduct measurements with ownexperts.

2. Propulsion machinery power shall be verified

during measurements.

3. Measurements shall be witnessed by a GLSurveyor.

B. Measuring Conditions

1. Sea Mode

1.1 Propulsion machinery shall produce the nec-essary power to reach the service speed of the vesselas contractually agreed on. Power shall not be lessthan 85 % of MCR.

1.2 Controllable pitch propellers, if any, to be innormal seagoing position.

1.3 A condition with operating stabilizers to beconsidered.

1.4 To exclude shallow water effects the mini-mum water depth required for measurements has to becalculated for each ship individually based on theDepth Froude Number. The loading condition should

be the same as specified in the contract. Deviationsshall be submitted to GL for approval prior to trials.For ships normally operating in shallow waters, corre-sponding conditions have to be chosen for measure-ments.

1.5 Sea state 3 (significant wave height approx.1,25 m) and a wind speed of 4 Bft should not be ex-ceeded. For more severe weather conditions, the ac-ceptance of measurements will be decided by GL on acase-by-case basis.

1.6 The course of the vessel shall be as straight as

possible. Minimum rudder movement is imperative.Rudder angles shall not exceed 2 degrees.

1.7 The ship shall be fully outfitted, and all sys-tems contributing to noise and vibration shall be in

normal seagoing condition, e.g. all auxiliary machin-ery, navigation instruments, radar sets, etc. shall be innormal operation throughout measurements. Thecommunication radio shall be turned on, but not oper-ating.

Mechanical ventilation and air-conditioning equip-ment shall be in normal operation (capacity to be inaccordance with design conditions). All air-conditioning systems shall be adjusted prior to meas-urements.

1.8 Noise and vibration caused by any unneces-sary human activity shall be avoided.

1.9 Passenger entertainment and public addresssystems shall be switched off.

1.10 No passengers shall be on board. Exceptionsmay be permitted.

1.11 Doors and windows shall, in general, beclosed.

2. Harbour Operation

2.1 Measurements are permissible for waterdepths smaller than for Sea Mode. The water depth

present during harbour measurements shall be re-ported.

2.2 The presence of large noise-reflecting areasin the vicinity of the vessel shall be reported.

2.3 The influence of external noise sources, suchas traffic, workshops, etc., shall be reduced to a mini-mum.

2.4 All machinery, mechanical ventilation andair-conditioning equipment to be running in normal

port condition, as contractually agreed on betweenowner and shipyard.

2.5 Requirements according to 1.7 to 1.11 applyas well.

3. Thruster Operation

3.1 Measurements shall be conducted in an opensea area. The water depth shall be reported.

3.2 Ship speed shall be close to zero.

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3.3 All machinery shall be running in normalcondition as necessary for Thruster Operation with notless than 70 % of full load for each thruster.

3.4 Additional noise measurements shall be taken

in selected pax and crew cabins during standby opera-tion of thrusters.

3.5 Requirements according to 1.5 and 1.7 to1.11 apply as well.

C. Performance of Measurements

1. Noise

1.1 Instrumentation

1.1.1 Integrating-averaging sound level metersshall be applied. These should be able to store themeasured data.

1.1.2 The instrumentation system including micro-phone, cable and recording devices shall meet re-quirements for a type 1 instrument as specified in IEC804.

1.1.3 The microphone shall be calibrated to havean essentially flat frequency response in a diffusesound field.

1.1.4 A windscreen shall be used for outdoor meas-urements.

1.1.5 If a windscreen is used for indoor measure-ments, the measured A-weighted sound pressure levelshall not be influenced by more than 0,5 dB (A).

1.1.6 1/1 or 1/3 octave band filters shall complywith the requirements of IEC 1260.

1.1.7 Class 1 sound calibrators complying with therequirements of IEC 942 shall be used.

1.1.8 Calibration of measuring instrumentation:

The compliance of the integrating-averagingsound level meter with requirements of IEC 804shall be verified by the manufacturer or otherauthorized organization at least every two years.

The compliance of the sound calibrator withrequirements of IEC 942 shall be verified by themanufacturer or other authorized organization atleast every two years.

The date of last verification and confirmation ofcompliance with relevant IEC standards shall berecorded. Calibration sheets shall be provided.

1.1.9 An instrument suitable of storing time signals

in case of subjectively annoying low-frequency sound(booming) or obvious tonal components shall be pro-vided.

1.2 Number of measurement positions

1.2.1 Noise level measurements in passengerspaces

1.2.1.1 Cabins

The total number of measurement positions to betaken in pax cabins depends on the net living space ofeach room belonging to the individual pax cabin.

net living space less than or equal to 20 m2:

one measurement position in the middle of theroom

net living space greater than 20 m2:

at least two measurement positions in the room.

On ships for which the total number of passengers isless than or equal to 150, noise measurements shall beconducted in each pax cabin.

On ships for which the total number of passengers isgreater than 150, the number of required measurement

locations are defined in Table 3.1, expressed in verifi-cation percentages.

1.2.1.2 Public spaces of type 1 and 2

Measurement positions shall be chosen in a way thatthe noise situation can be evaluated in each individual

public space.

In small public spaces with an area less than or equalto 40 m, at least one measurement position shall betaken in the centre of the room.

1.2.1.3 Corridors

Measurement positions shall be chosen where maxi-mum noise levels can be expected (especially close toair inlets and outlets of air-conditioning systems, cas-ings, etc.). Furthermore, the maximum distance be-tween each two measurement positions depends on theoperating condition and the emission zone as follows:

Sea Mode; aft of Frame C: 12 m

Sea Mode; forward of Frame C: 18 m

Harbour Operation; aft of Frame C: 18 m

Harbour Operation; forward of Frame C: 25 m

Thruster Operation; measurements not required

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Table 3.1 Required scope of noise measurements, passenger and crew spaces(Number of Passengers > 150)

Sea Mode HarbourOperation 2

ThrusterOperation 3Verification percentages 1

All hc All hc All hc

Indoor spaces aft of frame A

Passenger first-class cabins 4 50 10 20

Passenger standard cabins 4 25 10 20

Crew day and sleeping rooms 4 30 10 20

Crew mess and recreation rooms 4 100 25 50

Work spaces, control rooms, offices, etc.4

100

25

Indoor spaces between frame A and C

Passenger first-class cabins 25 10 10

Passenger standard cabins 25 10 10

Crew day and sleeping rooms 30 10 10

Crew mess and recreation rooms 100 25 25

Work spaces, control rooms, offices etc. 100 25

Indoor spaces between frame C and D




Crew mess and recreation rooms 25 25 25


Indoor spaces forward of frame D




Mess and recreation rooms 25 25 50


1 For spaces not referred to in this table, C.1.2.1 and 1.2.2 applies.

2 Especially spaces in the vicinity of main noise sources (where maximum noise levels can be expected or where obviously high noiselevels are observed during the noise survey).

3 Especially spaces close to thrusters (where maximum noise levels can be expected or where obviously high noise levels are observedduring the noise survey).

4 Passenger indoor spaces aft of frame A shall be considered during stern thruster operation only.

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1.2.1.4 Main staircases

Measurement positions shall be taken at each staircaseplatform of each main staircase in Sea Mode and Har-bour Operation.

1.2.1.5 Outdoor spaces

Total numbers of measurement positions mainly de-pend on the size of the passenger ship and on numberof air-conditioning and mechanical ventilation airsupply/exhaust openings located close to passengerrecreation areas.

In general, several measurement positions shall betaken on passengers open recreation deck spacesdirectly exposed to exhaust gas noise of the main

propulsion plant and auxiliary machinery. The sameapplies to recreation areas located close to air sup-

ply/exhaust openings of mechanical ventilation sys-tems.

The final noise measurement positions on passengersopen recreation deck spaces will be determined byGL.

1.2.2 Noise level measurements in crew spaces

1.2.2.1 Accommodation and work spaces

The measurement positions shall be chosen accordingto IMO Resolution A.486 (XII), Chapter 2.8.

On ships for which the total number of passengers isless than or equal to 150, noise measurements shall beconducted in each crew cabin for Sea Mode condition.

On ships for which the total number of passengers isgreater than 150, the number of noise measurementsrequired for Sea Mode condition is given in Table 3.1,expressed in verification percentages.

Number of measurement positions for Harbour Opera-tion and Thruster Operation are given in Table 3.1,expressed in verification percentages, irrespective ofthe number of passengers.

1.2.3 Acoustic privacy measurements

1.2.3.1 Sound insulation

Measurements shall be conducted according to ISO717/1 and ISO 140/4 in crew and passenger spaces.

Measurements shall be conducted in at least two cab-ins of each type.

1.2.3.2 Impact sound insulation

Measurements shall be conducted according to ISO717/2 and ISO 140/7 in crew and passenger spaces.

Measurements shall be conducted at least in two cab-ins located close to relevant spaces for each combina-tion of cabin type and floor construction.

1.3 Measurement procedure

1.3.1 General

1.3.1.1 The most relevant standards to be observed

are: ISO 2923

ISO 140

ISO 717

E DIN 45681

1.3.1.2 A maximum of three persons are allowed tostay in the same indoor space/cabin when the noisemeasurements are being conducted.

1.3.1.3 The equivalent continuous A-weighted soundpressure level in dB(A) shall be measured. The corre-sponding band levels of the 1/1 octave band mid fre-quencies of at least 31,5 Hz to 8 000 Hz shall bemeasured simultaneously. After each measurement, allmeasured data shall be stored on the hard disk of thesound level meter.

1.3.1.4 The calibration of the measuring instrumentsshall be checked immediately before and after each

period of use. The calibration level shall be measuredand stored after each calibration.

1.3.1.5 Overall sound pressure level in dB(A), filenumber of the data storage (ID number), measurement

location, noise limit according to hc target and subjec-tive noise impression shall be recorded and immedi-ately noted in measurement protocol sheets after re-cording, see Annex D.

1.3.1.6 The sound level instrumentation shall be setto "fast" response. The measuring time shall be at least15 seconds if the fluctuation of the overall sound pres-

sure level is equal to or less than 3 dB(A). If fluctua-

tions exceed 3 dB(A) or if the sound is cyclic orirregular, the instrument setting shall be changed to "slow" response and the measuring time shall be ex-tended to at least 30 seconds.

1.3.1.7 During each measurement, the microphoneshall slowly be moved horizontally and/or vertically

over a distance of approximately 0,5 m.

1.3.1.8 In spaces such as radio and radar rooms, careshould be taken to ensure that any electrical interfer-ence present does not give rise to a false indication ofthe noise level.

1.3.1.9 A microphone windscreen shall be used whenmeasuring noise levels on open deck spaces and also

below decks where there is any substantial air move-ment. When used for indoor spaces, 1.1.5 has to beobserved.

1.3.1.10 Wind noise, e.g. wind trash, singing or simi-lar effects has to be reported for surveyed outdoorspaces.

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1.3.1.11 For measurements in passenger spaces, it isrecommended to position the microphone at an aver-age height of approx. 1,4 m to cover both the positionof a sitting and a standing person.

1.3.1.12 The microphone position should not be closerthan 0,5 m to boundary surfaces, e.g. lining walls,ceilings, windows, floors and bulkheads.

1.3.2 Acoustic privacy

1.3.2.1 Measurements shall be conducted accordingto ISO 717-1, ISO 717-2, ISO 140/4 and ISO 140/7.

1.3.2.2 For sound transmission measurements be-tween corridor and cabin, the microphone position inthe cabin (receiver room) shall be located where pas-sengers normally stay.

1.3.3 Presence of secondary noise sources

In general, secondary noise sources (e.g. rattling,knocking and squeaking noises from doors, panels,furniture, fittings or fixtures, etc.) shall be eliminatedin crew and passenger accommodation spaces.

1.3.4 Presence of obvious tonal components

1.3.4.1 In general, obvious tonal components inpassenger and crew spaces will not be accepted forany of the conditions: Sea Mode, Harbour Operationand Thruster Operation.

1.3.4.2 Obvious tonal components audible in paxcabins and/or in passenger public spaces and/or increw accommodation spaces shall be reported, seeAnnex D.

1.3.4.3 The tone rating procedure, as mentioned inAnnex B, shall be applied in passenger spaces wheresteady noise with audible discrete tones is present. Ingeneral, the application of this tone rating proceduredoes not depend on the hc target, but will be handledin a stricter manner for ships with a hc target E, 1 or 2.

1.3.4.4 This procedure shall also be applied in crewaccommodation spaces on board ships with an hc

target of E, 1 or 2. For ships with an hc target 3 or 4,IMO Resolution A.468 (XII) shall be applied.

1.3.5 Presence of booming effects

1.3.5.1 In general, the presence of annoying low-frequency sound (booming effects) occurring in pas-senger and crew spaces during Sea Mode, HarbourOperation and Thruster Operation will not be ac-cepted.

1.3.5.2 Annoying low-frequency sound audible inpax cabins and/or in passenger public spaces and/or increw accommodation spaces shall be reported, seeAnnex D.

1.3.5.3 When booming effects are present in passen-ger spaces, the booming rating procedure as men-

tioned in Annex Bshall be applied, irrespective of thehc target chosen for the ship.

1.3.5.3.1 The procedure as described in IMO Resolu-tion A.468 (XII) shall be applied in crew accommoda-

tion spaces and does not depend on the hc target cho-sen for the ship.

1.3.6 Presence of impulse noise

1.3.6.1 In general, impulse noise in passenger andcrew spaces will not be accepted for any of the condi-tions: Sea Mode, Harbour Operation and ThrusterOperation.

1.3.6.2 The presence of impulse noise shall be de-termined according to the definition as given in AnnexB.

2. Vibration

2.1 Instrumentation

2.1.1 The equipment shall be calibrated at periodicintervals of not more than two years. Calibrationsheets shall be provided.

2.1.2 On non-magnetic floors, measuring sensorsshould preferably be mounted on a three-legged platewith a minimum weight of 1500 g.

2.1.3 The instrumentation shall allow for calcula-tion of the weighted rms value in terms of vibrationvelocity according to ISO 6954.

2.1.4 Provision shall be made for the storage of allspectra and a limited number of time records.

2.1.5 The instrumentation shall comply with re-quirements of ISO 8041.

2.2 Number of measurement positions

2.2.1 The required number of measurement posi-

tions depends on the vibration direction to be meas-ured (longitudinal, transverse or vertical).

2.2.2 Measurement positions for assessing longitu-dinal vibrations shall be chosen in a way that meas-urement results adequately reflect the global level. Atleast one measurement position should be chosen atthe inner bottom, the strength (weather) deck and thetop deck level.

2.2.3 Measurement positions for assessing trans-verse vibrations shall be chosen in a way that resultsadequately reflect the global level. Measurement posi-

tions should be located at the strength (weather) deckof the vessel and at the highest deck of ship. The lon-gitudinal distance of measurement positions shall notexceed Lpp/4.

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2.2.4 The scope of measurements in vertical direc-tion for passenger and crew accommodation areas,expressed in verification percentages, is listed in Table3.2.

2.2.5 In rooms/spaces of a more unique character,e.g. public spaces, open deck recreation areas, offices,mess rooms, etc., the vertical vibration level shall bemeasured individually for each room/space. Normally,measurements will be carried out in the centre of theroom.

2.2.6 For rooms/spaces with an area exceeding40 m2, several measurement positions shall be chosen(at least one position per 40 m2) in a way that subjec-tively high vibrations in vertical direction are covered.

2.3 Measurement procedure

2.3.1 The relevant standards are ISO 4867 and4868.

2.3.2 The velocity spectrum, achieved by an FFTanalysis of the measured time series, shall generally be

made available, i.e. during sea trials. The spectrumshall be stored.

2.3.3 If desired by GL experts, for instance if beat-ing occurs, time records of selected measurement

positions shall be recorded and stored.

2.3.4 To ensure comparability of the spectra, thefollowing parameters shall be applied for data acquisi-tion and signal processing:

measurement time per point: 1 min.

sampling rate: 300 1/s.

spectral frequency range: 1 Hz to 80 Hz

minimum spectral resolution: 0,2 Hz

FFT window function: flat top (if not available:Hanning window)

FFT averaging mode: linear averaging (stablemean)

2.3.5 The results shall be presented as weightedrms values in terms of vibration velocity.

Table 3.2 Required scope of vibration measurements, passenger and crew spaces, vertical direction

Verification percentages 1 Sea

Mode

Harbour

Operation

Thruster

Operation

Aft of frame B




Spaces between frame B and D

Passenger cabins, 1st

class 20

Passenger cabins, standard 10

Crew day and sleeping rooms 10

Spaces forward of frame D

Passenger cabins, 1st

class 20 30

Passenger cabins, standard 10 30

Crew day and sleeping rooms 10 30

1 For spaces not referred to in this table, C.2.2.5 and 2.2.6 applies.

2 For vessels equipped with stern thruster only.

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D. Survey Programmes

1. General

Different types of measurements which are to be con-

ducted on board shall be described in six individualSurvey Programmes:

Noise Vibration

Part I: Sea Mode Part V: Sea Mode

Part II: Harbour Operation Part VI: Thruster

OperationPart III: Thruster Operation

Part IV: Acoustic Privacy

At least three months prior to measurements the cor-responding Survey Programmes should be submittedto GL for approval.

All Survey Programmes shall be based on the finaldesign stage of the ship and shall be presented in formof an A4-sized document with numbered pages. Theuse of A3 format is restricted to drawings.

Moreover, programmes are meant to give the personsperforming measurements necessary background in-formation for a straightforward execution of meas-urements.

2. Data and drawings

2.1 Following items form the standard informa-tion required for approval of the Survey Programmes;additional documents can be required if deemed nec-essary.

2.2 General arrangement drawings of the ship(preferred scale 1:50, 1:100, 1:250 or 1:500).

2.3 Machinery arrangement drawings, including

casing arrangement and machinery legend (preferredscale 1:100, 1:250 or 1:500).

2.4 Drawing for thermal, fire and sound protec-tion, including insulation details (e.g. sketches, mate-rial properties, etc.).

2.5 Floor and deck covering drawings (thermal,fire and sound protection), including insulation details(e.g. sketches, material and acoustical properties, etc.).

2.6 General arrangement drawings of mechanicalventilation systems, including location of HVAC

rooms.All relevant structure-borne and airborne noisesources shall be indicated in the drawings (includingthe air supply / exhaust openings of mechanical venti-lation and HVAC systems).

2.7 Data and drawings required according to ISO717-1 and ISO 717-2.

2.8 Acoustic privacy plan (see Annex B).

2.9 Detailed description (sketches, material prop-erties, etc.) of noise abatement measures which are

provided in cabins adjacent to machinery spaces, cas-ings, trunks, etc.

3. Content of each survey programme

3.1 Target hcpass and hccrew

3.2 Ship particulars

3.3 Main data of propulsion plant, propeller,

auxiliary engines.

3.4 Environmental conditions expected duringmeasurements.

3.5 Permissible range of wind speed, sea stateand water depth.

3.6 Operating conditions expected during meas-urements.

Loading condition, displacement, draughts, power andspeed of main engine, propeller and auxiliary machin-

ery.

3.7 Measurement instrumentation

3.8 Prepared measurement protocol sheets andsketches for each emission zone.

Table indicating for each measurement position: num-ber, location (frame, transverse offset from CL, decklevel), measurement direction, kind and area [m] ofspace/room and limit values corresponding to hc tar-get.

Measurement positions plotted in general arrangement

plans indicating number, position and direction to bemeasured.

E. Survey Report

A Survey Report contains all results of each meas-urement on board, executed on the basis of the SurveyProgrammes.

Each Survey Report shall contain the following docu-mentation:

1. Ship and machinery data

2. Loading condition

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3. Any deviation from the Survey Programmes,e.g., environmental and operation condition, meas-urement locations, number, instrumentation etc.

4. Wind speed and direction, sea state (esti-

mated wave height and direction), ship course andspeed

5. Filled-in measurement protocol sheets fornoise and vibration.

6. Calculation of overall hc achieved on thebasis of measurement results.

7. All measured 1/1 and/or 1/3 octave bandnoise levels shall be submitted (CD, diskettes or via e-

mail).

8. All measured vibration spectra shall be sub-mitted (CD, diskettes or via e-mail). The same appliesto selected time series if desired by GL Surveyor.

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Section 4

Calculation Procedure ofhcClass_Notation

A. Determination of Single hc

The measured overall values for each individual meas-uring location during the acceptance tests (see Section3) are transformed to the corresponding single hc onthe basis of the limits given in Section 2.

The measurement values must not be rounded, i.e.:

A measured noise level of 46,1 dB(A)exceeds a given limit of 46 dB(A).

A measured vibration level of 3,21 mm/sexceeds a given limit of 3,2 mm/s.

B. Averaging of Single hc

All hc have to be determined separately for passengerand crew spaces.

For hcClass_Notation E, 1 and 2 the single hc must notexceed the desired hcClass_Notationby more than 2 cate-gories.

For hcClass_Notation 3 and 4 the measured noise and vi-bration levels must not exceed the respective limitvalues by more than 2 dB or 1,0 mm/s.

If the single hc is smaller than the desiredhcClass_Notation, the latter must be used for the averagehc calculation.

For vibration only: In a room/space with severalmeasurement positions, the target hc shall not be ex-ceeded at more than one position.

1. Noise

1.1 The hcSPL_Cabins is defined as the arithmeticmean value (average hc) of all single hc determinedduring the required measurements for the sound pres-sure level in passenger and crew cabins, according tothe following ranges:

hcSPL_Cabins= E for average hc = 0,00 to 0,25

hcSPL_Cabins= 1 for average hc = 1,00 to 1,25



hcSPL_Cabins= 4 for average hc = 4,00

1.2 The hcSPL_Others is defined as the arithmeticmean value (average hc) of all single hc determinedduring the required acceptance trials for the sound

pressure level in passenger and crew spaces other thancabins, according to the following tolerances:

hcSPL_Others= E for average hc = 0,00 to 0,35

hcSPL_Others= 1 for average hc = 1,00 to 1,35



hcSPL_Others= 4 for average hc = 4,00

1.3 The hcAcoustic_Privacy is defined as the arithme-

tic mean value (average hc) of all single hc determinedduring the required measurements for the sound andimpact sound insulation, according to the followingtolerances:

hcAcoustic_Privacy = E for average hc = 0,00 to 0,35

hcAcoustic_Privacy = 1 for average hc = 1,00 to 1,35

hcAcoustic_Privacy

= 2 for average hc = 2,00 to 2,35

hcAcoustic_Privacy = 3 for average hc = 3,00 to 3,35

hcAcoustic_Privacy = 4 for average hc = 4,00

2. Vibration

2.1 The hcLongVib is the highest value of all sin-gle hcdetermined by measurements of the longitudinalvibrations during the required acceptance trials.

2.2 The hcTransvVib is the highest value of all sin-gle hcndetermined by measurements of the transverse

vibrations during the required acceptance trials.

2.3 The hcVertVibis defined as the arithmetic meanvalue (average hc) of all single hc determined bymeasurements of the vertical vibrations during therequired acceptance trials, according to the followingtolerances:

hcVert_Vib = E for average hc = 0,00 to 0,35

hcVert_Vib = 1 for average hc = 1,00 to 1,10

hcVert_Vib = 2 for average hc = 2,00 to 2,10

hcVert_Vib = 3 for average hc = 3,00 to 3,10hcVert_Vib = 4 for average hc = 4,00

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C. Determination ofhcClass_Notation

The hcClass_Notation is determined separately for passen-ger and crew spaces.

The hcClass_Notation is the highest value out of the fol-

lowing six criteria, taking the three types of conditionsinto account (Sea Mode, Harbour Operation andThruster Operation):

Noise: hcSPL_Cabins

hcSPL_others

hcAcoustic_Privacy

Vibration: hcLong_Vib

hcTransv_Vib

hcVert_Vib

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Annex A

Standards

A. General

1. If these Rules contain procedures deviatingfrom the relevant standards, these Rules shall have

priority.

B. Standards

1. Noise standards

IMO Resolution A.468 (XII): 1982, "Code onnoise levels on board ships"

IMO Resolution A.343 (IX): 1975-11, "Rec-ommendation on Methods of Measuring NoiseLevels at Listening Posts"

ISO 2923, 1996-12, "Acoustics Measurementof noise on board vessels"

ISO 31-7: 1992-09, "Quantities and units of

acoustics"

IEC 651: 2001-10, Ed. 1.2, "Sound level metres"

IEC 1260: 1995-08 and IEC 1260-am1: 2001-09, Electroacoustics - Octave-band and frac-tional-octave-band filters"

IEC Publication 804, and amendment no. 1,1989, "Integrating/averaging sound level me-ters"

IEC 942: 1997-11, Ed. 2.0 and IEC 942-am1:200-10, Ed. 2.0 "Sound calibrators"

ISO 717/1: 1996-12, "Acoustics Rating ofsound insulation in buildings and of buildingelements Part 1: Airborne sound insulation in

buildings and interior elements"

ISO 717/2: 1996-12, "Acoustics Rating ofsound insulation in buildings and of buildingelements Part 2: Impact sound insulation"

ISO 140/4: 1998-12, "Acoustics Measurementof sound insulation in buildings and of buildingelements Part 4: Field measurements of air-

borne sound insulation between rooms"

ISO 140/7: 1998-12, "Acoustics Measurementof sound insulation in buildings and of buildingelements Part 7: Field measurements of impactsound insulation of floors"

ISO 1999: 1990-01, "Acoustics Determinationof occupational noise exposure and estimationof noise-induced hearing impairment"

E DIN 45681: 1992-01, "Bestimmung der Ton-haltigkeit von Geruschen und Ermittlung einesTonzuschlages fr die Beurteilung von Ge-ruschimmissionen" ("Detection of tonal com-

ponents of noise and determination of a tone ad-justment for the assessment of noise imission")

2. Vibration standards

ISO 6954: 2000E, "Mechanical vibration Guidelines for the measurement, reporting andevaluation of vibration with regard to habitabil-ity on passenger and merchant ships"

ISO 2631-1: 1997 (E), "Mechanical vibrationand shock Evaluation of human exposure towhole-body vibration Part 1: General require-ments"

ISO 2631-2: 1989 (E), "Mechanical vibrationand shock Evaluation of human exposure towhole body vibration Part 2: Continuous andshock induced vibration in buildings(1 - 80 Hz)"

ISO 4867: 1984 (E), "Code for the measurementand reporting of shipboard vibration data"

ISO 4868: 1984 (E), "Code for the measurementand reporting of local vibration data of shipstructures and equipment"

ISO 8041: 1990 (E), "Human response to vibra-tion Measuring instrumentation"

Germanischer Lloyd, Ed. 2004, "Rules for Clas-sification and Construction, I Ship Technol-ogy, Part 1 Seagoing Ships, Chapter 2 Ma-chinery Installations"

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Annex B

Definitions

A. Important Definitions

Angular frequency, circular frequency:

[rad/s] is the product of the frequency of asinusoidal quantity and the factor 2 :

= 2 f

Acoustic privacy:

"Privacy" from an acoustical point of view, i.e.

the state of being alone and relatively undis-turbed with regard to noise emissions fromneighbouring cabins, sanitary cells, corridors,

public spaces, open deck recreation spaces, ser-vice spaces, etc. (sound and impact sound insu-lation).

Acoustic privacy plan:

Drawings showing the arrangement of all cabintypes including noise limit values to be kept.See also "cabin type".

Auxiliary machinery:

Machinery, other than main propulsion machin-ery, operating when the ship is in normal ser-vice, e.g. auxiliary diesel engines, turbo-generators, hydraulic motors and pumps, com-

pressors, boilers, ventilation fans, gears, pumps.

Abatement measures:

Noise and/or vibration control measures, e.g.with the aim of reducing the airborne and/orstructure-borne noise emission as well as of vi-

bration levels of structures, equipment, etc.

A-weighted sound pressure level LAeq orLAeq,T:

The A-weighted equivalent continuous soundpressure level using the frequency weighting"A" as specified in the IEC publication 60651within a measurement time interval T.

Beat, beating:

Periodic amplitude variations of an oscillationresulting from the superposition of two excita-tion sources of slightly different frequencies.Beating which occurs in the audible frequencyrange is experienced as being annoying.

Boom, booming:

Deep, hollow resonant low-frequency sound inthe range between 16 and 125 Hz. Booming ismainly due to one or more discrete tonal com-

ponents of significantly greater amplitudes than

those of the adjacent spectrum level. Booming isexperienced as being annoying and can only bedetected subjectively. See also "steady noisewith audible discrete tones".

Booming rating procedure:

Procedure for measuring and assessing the oc-currence of audible discrete tones below 125 Hz(booming effect). The procedure developed byGL is based on experimental investigations on

board ships.

As result of this procedure a booming adjust-ment (CB in dB(A)) is established. The noise

rating level has to be used for further evaluation.

Bathroom:

A room in which there is, e.g. a shower and/or abathtub, a washbasin, a toilet, etc. In theseRules, the area of a bathroom is greater than6 m

2.

Cabin type:

Cabins with different types of interior systems(lining walls, ceilings, doors, etc.), floor con-structions, floor coverings, etc. See also "Acous-tic privacy plan".

Crew spaces:

Cabins, offices (for carrying out the ship's busi-ness), hospitals, mess rooms, recreation rooms(such as lounges, smoke rooms, cinemas, librar-ies, hobby and game rooms) and open recreationareas used by officers, hotel staff and crew.

Corridors:

Passageways/alleyways arranged in crew andpassenger spaces.

Depth Froude Number:

The Depth Froude Number is v g h ;

v = ship speed [m/s], g = gravitation accelera-tion [m/s2], h = water depth [m].

Displacement :Displacement of the vessel [t].

Dressing-room:A room for putting on clothes and a place whereclothes are stored, usually in a built-in ward-robe. In these Rules, the area of a dressing room

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is greater than 8 m2. Otherwise the dressing

room is not to be defined as a "room".

Drivingpoint impedance:

In a mathematical sense, the complex ratio of

force to velocity taken at the same point in amechanical system during simple harmonic mo-tion.

Engine or shaft speed:

Number of revolutions per minute [rpm]

Equivalent continuous sound pressure levelLeq or Leq,T :

Unweighted sound pressure level of a continu-ous steady sound. Within a measurement timeinterval T this sound has the same mean squaresound pressure as a sound under considerationthat varies with time. It is expressed in decibels

by the following equation:

( )

( )2t2

eq eq,T 102 1 t o1

p t1L = L = 10 log dt

t - t p

(t2 t1) = period T over which the average istaken, starting at t1 and ending at t2

p (t) = unweighted instantaneous rmssound pressure between 16 and16 000 Hz

p0 = 2 105 Pa (reference level)

Exposure time (vibration):

A distinction is made as to whether publicspaces are characterized by "short" or "long"exposure times. Typical public spaces with shortexposure times are receptions, shops, alleyways,staircases, lobbies, sanitary rooms, etc. Typicalpublic spaces with long exposure times are res-taurants, cafeterias, bars, theatres, cinemas,lounges, conference rooms, hospitals, discos,etc.

Fluctuating noise:

The measured sound pressure level (e.g. pointer

of the display) varies more than 3 decibelswith the "slow" meter characteristic switchedon. Impulse noise must be excluded.

Frame A, B, C, D:

See "imission zones"

Hard floor:

Floor characterized by a relatively "hard" final

covering, e.g. uncovered steel deck, wood, tiles,marble, PVC, etc. fitted on top of floating floors,viscoelastic floors, normal deck components,steel decks, etc.

Hotel staff spaces:

See "crew spaces"

HVAC:

Heating, venting and air-conditioning system Imission zones:

Typical noise and vibration imission zones aredefined as follows:

Frame A:

A virtual frame section at a maximum dis-tance of 3 times the propeller diameter infront of the propeller plane.

Frame B:

A virtual frame section or the aft main

vertical fire zone bulkhead at a distance ofat least 0,15 Lpp in front of the propellerplane.

Frame C:

Forward bulkhead of forward engine room(main or auxiliary diesel engine room).

Frame D:

20 m aft of rear bulkhead of bow thrusterroom.

Impedance:

See "driving-point impedance"

Impulse noise:

Noise of less than one second duration that oc-curs as an isolated event or as one of a series ofevents with a repetition rate of less than15 times per second. The presence of impulsenoise shall be determined by obtaining the dif-ference between the equivalent continuoussound pressure level measured with timeweighting "impulse" and "fast". If the differenceis more than 2 dB, the presence of impulse noisemay be assumed.

Impulse rating procedure:

Procedure for measuring and assessing the oc-currence of impulse noise events. As result ofthis GL procedure an impulse adjustment CI

[dB(A)] is established. The noise rating levelhas to be used for further evaluation.

Integrating sound level meter:

A sound level meter designed or adapted tomeasure the level of the mean squared time av-eraged A-weighted sound pressure level (IEC804).

ISO noise rating (NR) number:

The number found by plotting the 1/1 octaveband spectrum of the NR curves given in ISO

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Standard R 1996-1967 and selecting the highestnoise rating curve tangent to the spectrum.

Machinery spaces:

All spaces containing propulsion machinery,

boilers, steam and internal combustion engines,generators and major electrical machinery, oilfilling stations, refrigerating, stabilizing, hydrau-lic units, air-conditioning cooling compressors,etc.

Maximum continuous rating (MCR):

Designed maximum continuous power rating ofmain engines.

Measured SPL:

The sound pressure level measured with a soundlevel meter or sound measurement instrumenta-

tion. The measured SPL shall be expressed toone decimal place.

Net living space:

Total living area of an individual pax cabinwithout sanitary cell and balcony in square me-tres.

Noise level:

See "A-weighted sound pressure level".

NRC:

Noise rating curve, see "ISO noise rating (NR)

number".

Noise rating level:

The noise rating level LA, r is defined as follows:

LA,r = Aeq T I BL C C C+ + + [dB(A)]

= noise rating level [dB(A)]

LAeq = measured overall A-weighted soundpressure level

CT, CI, CB = adjustments as result of the tone,

impulse and booming rating pro-

cedure Noise FEM:

The NoiseFinite Element Method (Noise FEM)developed by Germanischer Lloyd makes it pos-sible to predict the propagation of structure-borne noise energy in complex ship structures.For this purpose the Noise FEM uses the geome-try and material data of existing global finiteelement models created mainly for strength andvibration computations. Noise FEM is based onprinciples also used in SEA. For detailed infor-mation see:

C. Cabos and H. G. Matthies:"A method for the prediction of structure-borne noise propagation in ships", Proceed-ings of the 6th international congress on

sound and vibration 1999, Technical Univer-sity of Denmark

Normal service speed:

Shaft speed and propulsion power correspond-

ing to service speed contractually agreed on, atleast at 85 % MCR.

Officers' spaces:

See "crew spaces".

Overall frequency-weighted rms value:

The overall frequency-weighted rms value hasto be determined according to ISO 6954, secondedition 2000-12-15.

Overhang:

An overhang in this context is the part of a deck

area protruding the vertical support (walls, pil-lars).

Passenger:

Any person on board other than members of thecrew or persons employed or engaged in any ca-pacity for the business of that ship.

Pax cabins:

All types of cabins (e.g. suite, first-class, stan-dard cabin, etc.) intended to be used by passen-gers.

Passenger indoor spaces:

All areas used by passengers in enclosed spacesof the vessel.

Passenger outdoor spaces:

All outdoor recreation areas to where passengeraccess is foreseen.

Public spaces, type 1:

Enclosed spaces for passenger recreation wherethe noise level normally is or may be high whenin use, e.g. entertainment spaces such as discos,theatres, cinemas, gymnasiums, dance floors,stages, etc.

The sound pressure levels for the 1/1 octaveband mid frequencies that should not be ex-ceeded in above spaces are listed in Table B.1.

Public spaces, type 1a:

Separated deck/floor spaces of public spacestype 1 such as dance floors, stages and gymna-sium floors.

Public spaces, type 2:

Enclosed spaces for passenger recreation wherethe noise level is not normally high (approx.75 dB(A) or can be expected to be low (approx.

65 dB(A)) when in use, e.g. conference rooms,casinos, restaurants, bars, shops, atriums, galler-ies, receptions, observation lounges, libraries,etc.

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Table B.1 Sound pressure levels for public spaces type 1

1/1 octave band limit value 1/1 octave band limit value

31,5 Hz 65 dB(A) 1 000 Hz 91 dB(A)

63 Hz 72 dB(A) 2 000 Hz 94 dB(A)

125 Hz 78 dB(A) 4 000 Hz 94 dB(A)

250 Hz 85 dB(A) 8 000 Hz 94 dB(A)

500 Hz 88 dB(A)

RMS value:

The rms value of a single-valued function, f(t),over an interval between t1 and t2 is

( )

1 2t2 2

t1

2 1

f t dtrms value

t t

=

Room space:

Total room area of an individual public space

[m2]

SEA:

Statistical Energy Analysis. For detailed infor-mation see:

R. H. Lyon and R. G. DeJong,"Theory and Applications of Statistical En-ergy Analysis", Butterworth Heinemann,Boston 1995

Soft floor:

Floor characterized by a relatively soft finalcovering, e.g. carpets, carpeting, etc., fitted ontop of floating floors, viscoelastic floors, nor-mal deck compounds, steel decks, etc.

Sound pressure level "L":

A measure of sound level on logarithmic scale

given by:

[ ]100

pL 20 log dB

p

=

where:

p = rms value of measured sound pressurebetween 16 and 16 000 Hz

p0 = 2 105 Pa reference level

Steady noise without audible discrete tones:

Level fluctuations equal to or less than 3decibels. This type of noise is frequently re-ferred to as "broad-band" noise. Obvious tonalcomponents of noise (tonality and/or booming)in the whole audible frequency range between

16 and 16 000 Hz are absent or negligiblysmall.

Steady noise with audible discrete tones:

This type of noise has components at one ormore discrete frequencies having significantlygreater amplitudes than those of the adjacentspectrum level. Audible discrete tonal compo-nents of noise (tonality and/or booming) canoccur in the whole audible frequency range be-tween 16 and 16 000 Hz.

Sanitary cell:

A space in which there is, e.g. a shower and/orbathtub, a washbasin, a toilet, etc. In theseRules, the room space of a sanitary cell is lessthan or equal to 6 m

2. Sanitary cells are not de-

fined as "rooms".

Suite:

First-class passenger cabin/space with a set ofat least two adjacent rooms, e.g. bedroom, liv-ing room and/or sitting room, bathroom, dress-ing room, etc.

Tonality, annoying discrete tone:

A sound wave whose instantaneous soundpressure varies essentially as a simple sinusoi-dal function of time (pure tone). Tonality is ex-perienced as being annoying and can only bedetected subjectively. Tonality is defined in thefrequency range between 125 and 16 000 Hz. Itis mainly caused by main reduction gears,pumps, air-conditioning cooling compressorunits, thruster gears, HVAC inlet and outletopenings, etc.

Tone rating procedure:

Procedure for measuring and evaluating theoccurrence of tonality. It was developed byGermanischer Lloyd on the basis of nationalstandards and experimental investigations on

board ships.As a result of this procedure, a tone adjustment

figure CT[dB(A)] is established. The noise rat-ing level has to be used for further evaluation.

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Annex C

Recommendations to Reduce Noise and Vibration

A. General

1. To maintain the required noise and vibrationlevels, various investigations and noise and vibrationreduction measures are recommended. This is true forthe planning, design, fabrication and testing phase of anewbuilding.

B. Considerations Regarding ExcitationForces

By nature, the reduction of noise and vibration excita-tion forces is the most effective way to reduce thenoise and vibration levels. Therefore it is recom-mended:

to optimise the ship's lines by model tests inorder to achieve an appropriate wake distribu-tion

to optimise the propeller design with regard tonoise and vibration excitation by cavitation tank

tests to take into account the noise and vibration

excitation characteristics of main and auxiliarymachinery, gear, bow thruster, etc. by adequatechoice of suppliers

C. Theoretical Investigations

1. Noise and vibration aspects should be con-sidered as early as possible in the design process.

2. The extent of theoretical investigations nec-essary depends on the experience of the yard with therelevant ship type and the hc which shall be achieved.As a guideline the analyses summarised in Table C.1.are recommended.

The following types of investigations are distin-guished:

Review of General Arrangement Plan

Prior to detailed investigations, the general arrange-ment plan is reviewed with regard to noise and vibra-tion.

Local Vibration Calculation

Natural frequencies of plate fields, stiffeners and smallregularly stiffened panels are estimated by means of

empirical formulas. The objective is to avoid reso-nance with main excitation frequencies. Added massesas well as hydrodynamic masses have to be consid-ered. Attention should especially focus on local struc-tures in vicinity of excitation sources (e.g. main pro-

pulsion, bow and stern thrusters) as well as on struc-tural components of public, living and working spaces.

Natural frequencies of all structural components shallbe chosen to have a sufficient margin to main excita-tion frequencies.

Noise Prediction

A noise prediction is conducted at an early designstage. Semi-empirical noise prediction programmesare applied to predict the average airborne noise lev-els. Noise limits specified for passenger and crewspaces are compared with predicted values.

Global Vibration Level Prediction

In a global vibration level prediction, the vibrationlevel at "global" points of the ship structure is esti-mated on the basis of a forced vibration calculation inthe lower frequency range (approx. 1 Hz to 20 Hz).

Dynamic magnification due to local resonances ofplate fields, stiffeners or panels is not considered.These local structural systems are investigated sepa-rately (see "Local Vibration Calculation").

The vibration level is estimated for relevant loadingconditions at representative points of the ship struc-ture.

If the expected vibration level exceeds specified lim-its, modifications of the steel structure, a differentnumber of propeller blades, arrangement of compensa-tors, etc. are proposed as possible means of improve-ment.

Detailed Vibration Level Prediction

A detailed vibration level prediction represents anextension of a global vibration level prediction, i.e. thedynamic magnification due to vibrations of large deck

panel structures is considered. The distribution ofhomogeneous and inhomogeneous masses on decks istaken into account as realistically as possible.

Detailed Impedance Investigation

Driving-point impedance levels (frequency rangeapprox. 50 to 300 Hz) of machinery foundations, shellconstructions above the propeller and of other criticalareas are determined by means of detailed local finite

element models as early as possible during the designstage. The aim of such an investigation is to optimizerelevant parts of the ship structure from an acoustical

point of view.

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NoiseFEM Analysis / Statistical Energy Analysis(SEA)

With a SEA or a NoiseFEM analysis, the soundpropagation within the structure is predicted. Consid-

ering the main structural members, the structure-bornenoise intensity flow is calculated for each subsystemof the SEA/NoiseFEM model. Then the energy levelwithin each subsystem is used for predicting averagestructure-borne and airborne noise levels in the ship.

D. Secondary Measures

1. If the theoretical investigations reveal that therequired noise and vibration levels probably can not

be attained secondary measures should be foreseen,i.e.:

isolation (resilient supports for instance)

insulation, encapsulation

damping (floating floors for instance)

compensation of vibration excitation forces

silencing

structural modifications

E. Supplementary Measurements duringProduction Phase

1. It is recommended to carry out test bed noiseand vibration measurements for the machinery com-

ponents in order to check the adherence to noise andvibration specifications agreed on with suppliers.

2. During outfitting stage the local vibrations ofdeck structures should be measured (impact or/andexciter measurements) to verify calculation results andto identify and rectify local structural deficiencies.

3. During outfitting stage the impedance of ma-chinery foundations should be measured to verify cal-culation results and to identify and rectify local struc-tural deficiencies.

Table C.1 Recommended theoretical investigations for seagoing cruise ships (v > 25 knots)

Seagoing passenger ships

hcType of investigation

E 1 2 3 4

Review of General Arrangement 1 z z z z z

Local Vibration Calculation z z z z z

Noise Prediction 1 z z z z z

Global Vibration Level Prediction z z

Detailed Vibration Level Prediction z z

Detailed Impedance Investigation z z

Detailed Noise Analysis (e.g. NoiseFEM Analysis, SEA Analysis etc.) 1 z z

z = Strongly recommended

= Recommended

= Recommended only if experience with similar ships is not available

1 The occurrence of tonality and/or booming in pax cabins and public spaces will be strictly assessed for hc E to 2(see Section 3, C.1.3.4).

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Annex D

Protocol Sheet

A. Measurement Protocol Sheet

Measurement Protocol Sheet (Noise)

No. Type of room MP-No

.

(Measu

rementPointNo.)

File(ID

)-No.

Sound

LevelMeter

MeasuredNoiseLevel

[dB(A)]

NoiseL

imitacc.tohctarget

[dB(A)]

Machin

eryNoise(e.g.engine,

gear,propeller,pumpsetc.)

HVAC-Noise,ventilationetc.

Rattling

Noise

Boomin

g

Tonality

Remark

Auditory Impression(Subjective Judgement)

Yard:

Owner:

Ship's name:

Kind of voyage:

Condition:

Hc target:

Subjective judgement of noise events (auditory impression) has to be carried out during the noise measurement andto be reported:+ => Noise event is weakly audible, but is not dominating the overall SPL++ => Noise event is clearly audible and is dominating the overall SPL

+++ => Noise event is clearly audible and is very annoying

Page .......... of ..........

Date ..........................

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