Brüel & Kjær 4448 Series User Manual
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Brüel & Kjær 4448 Series User Manual

Personal noise dose meter
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USER MANUAL
Personal Noise Dose Meter
Type 4448
 
BE 1844 – 12
English 

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  • Page 1 USER MANUAL Personal Noise Dose Meter Type 4448   BE 1844 – 12 English ...
  • Page 3 Personal Noise Dose Meter  Type 4448 User Manual BE 1844 – 12 April 2016  www.bksv.com...
  • Page 4 Sira 07ATEX2032X. The certificate number Health and Safety Considerations includes an ‘X’ suffix indicating that special This apparatus has been designed and tested in accordance conditions of certification apply, see page 3 for Safety with IEC/EN 61010 – 1 ANSI/UL 61010 – 1 more information.
  • Page 6 Brüel & Kjær has made every effort to ensure the accuracy of document may be construed as granting, by implication, or the information contained in this document. No responsibility otherwise any license or right to use any of the trademarks is accepted for any errors or omissions herein.

  • Page 7: Table Of Contents

    Contents CHAPTER 1 Introduction.......................... 1 About This Manual........................ 1 Conventions Used in this Manual ..................... 1 What is Type 4448? ........................ 1 Instrument and Kit Components .................... 3 Instrument .......................... 4 Kit.............................. 4 CHAPTER 2 Getting Started ........................ 7 Initial Setup.......................... 7 Charging Type 4448 ........................ 7 Switch On and Off ........................ 10 Configuration on Instrument .................... 10 Calibration .......................... 11 Mounting Type 4448....................... 11 Making a Measurement...................... 12 Using Preset Measurement Time ................... 14 Reviewing Measurement Data on the Instrument .............. 14 Alarm Settings......................... 15 CHAPTER 3 Calibration .......................... 17 CHAPTER 4 Post‐processing with Protector Type 7825 ................
  • Page 8 CHAPTER 5 Theory ...........................  27 Human Hearing Basics...................... 27 Noise‐induced Hearing Loss .................... 28 Measurements with Noise Dose Meters................ 30 What is Measured ........................ 30 The Importance of Peak Levels.................... 32 The Different Approaches to Taking Measurements .............  32 Which Approach to Choose? .................... 34 Things to Keep in Mind when Doing Dose Meter Measurements .........  35 Using Type 4448 to Select Hearing Protection ...............  35 Next Steps .......................... 36 CHAPTER 6 Specifications ........................ 37 APPENDIX A Glossary.......................... 41 INDEX ................................ 49...

  • Page 9: Introduction

    Chapter 1 Introduction About This Manual This user manual describes Personal Noise Dose Meter Type 4448 and connection to Protector PC Software for Calculation of Personal Noise Exposure Type 7825. This manual is divided into the following sections: • Chapter 1 – Introduction: Brief overview of the manual and Type 4448 •...
  • Page 10 Personal Noise Dose Meter Type 4448 – User Manual Type 4448’s robust design enables noise exposure measurements even in harsh environments. All Type 4448 versions come with a windshield, which provides extra protection for the microphone. Two models are available, the Intrinsically Safe (IS) model (Type 4448-002), which is designed to be used in hazardous areas requiring IS approvals (see Intrinsically Safe Versions, below, and Specifications) and the standard model (Type 4448-001), which is not designed to be used in potentially explosive environments.

  • Page 11: Instrument And Kit Components

    CHAPTER 1 Introduction Intrinsically Safe Versions Type 4448-002 is the IS model, meeting the requirements of ATEX EEx ia I M1, EEx ia IIC T2 II 1 G. The following instructions apply to equipment covered by certificate number SIRA 07ATEX2032X for Type 4448-002: the certificate number includes an ‘X’ suffix indicating that the following special conditions of certification apply: •...

  • Page 12: Instrument

    Personal Noise Dose Meter Type 4448 – User Manual 1.3.1 Instrument All functions of Type 4448 are operated with two pushbuttons: Left (L) and right (R). Fig.1.1 Type 4448 1. L pushbutton 2. R pushbutton 3. Status indicator 4. Display 5. Windshield 6. IR sensor 110413 1.3.2 There are two configurations. Kits with one, three or five Type 4448 units (see Fig.1.2) contain: •...
  • Page 13 CHAPTER 1 Introduction Fig.1.2 Kit containing five  Type 4448 units Also showing optional Sound Calibrator  Type 4231 additional 3‐way  Charger ZG‐0860 Kits with 10 Type 4448 units contain the above and: • Additional 3-way Charger ZG-0860 • Extension Cable AO-1943 for linking chargers • Additional set of spare windshields (set of 5; DS-1174) ✐...
  • Page 14 Personal Noise Dose Meter Type 4448 – User Manual...

  • Page 15: Chapter 2 Getting Started

    Chapter 2 Getting Started Initial Setup Before using Type 4448 the first time: 1) Fully charge the unit (section 2.1.1). 2) Switch on the unit and perform initial parameter setup (section 2.1.3). 3) Calibrate the unit (section 2.1.4 and chapter 3). The unit is now ready for a first measurement; however, before making on-site measurements, you may want to: 4) Install and run the PC software (Protector Type 7825 ;...
  • Page 16 Personal Noise Dose Meter Type 4448 – User Manual Fig.2.1 Slide in a new adaptor 110525 3) To change the adaptor: firmly push the plastic latch on the body and slide the adaptor out of the guide. Fig.2.2 Depress latch to  remove adaptor 110524 ⚠ Never charge any version of Type 4448 in a hazardous area. WARNING: To charge one, two or three Type 4448: 1) Plug Power Supply ZG-0864 into either of the two DC connectors on the back of the 3-way...
  • Page 17 CHAPTER 2 Getting Started When a unit is fully charged, the charger will switch to trickle-charge mode to maintain the charge without damaging the battery through overcharging. To charge more than three Type 4448s simultaneously: 1) Plug Power Supply ZG-0864 into either of the two DC connectors on the back of a 3-way charger.

  • Page 18: Switch On And Off

    Personal Noise Dose Meter Type 4448 – User Manual 2.1.2 Switch On and Off  Switch On Press the L pushbutton (no need to hold it in). The device will run through a short start-up sequence, showing the unit model number and firmware version, followed by a custom text screen (see section 4.2, page 23 for information on configuring this text).

  • Page 19: Calibration

    CHAPTER 2 Getting Started • Flashing LED under specific conditions) dB ALARMS YES, NO: • (0:00 – no preset time; 30-minute steps up to 12 hours of measurement) PRESET MODE • : enter locked mode when starting a measurement) AUTO YES, NO •...

  • Page 20: Making A Measurement

    Personal Noise Dose Meter Type 4448 – User Manual Fig.2.4 Type 4448 mounted  (with pins) on the  shoulder 10 cm from  the ear with the  microphone  approximately 4 cm  above the shoulder 110435 Type 4448 can be equipped with different mounting clips to provide the best fit depending on the wearer’s activity and or clothes: • The default mounting solution is a pair of crocodile clips. Using these is quick and materials will not be pierced •...
  • Page 21 CHAPTER 2 Getting Started 2) Type 4448 will show a countdown on the display: START 3...2...1 During this time the measurement can be aborted by releasing the pushbuttons. Once the measurement run has begun, will appear in the top left of the screen. During measurements, Type 4448 will alternate between two screens: one showing the battery and memory status, the other showing the instantaneous SPL and elapsed measurement time.

  • Page 22: Using Preset Measurement Time

    Personal Noise Dose Meter Type 4448 – User Manual Using Preset Measurement Time Type 4448 can be programmed for a preset measurement time (section 2.1.3). This feature makes it easy to repeat measurements with the same duration. Start a measurement with preset measurement as for a manually controlled measurement, by holding both the L and R pushbuttons simultaneously pressed for 3 seconds.

  • Page 23: Alarm Settings

    CHAPTER 2 Getting Started Table 2.2 OSHA display sequence for Type 4448 in default and PRO. MODE display modes – If there is no corresponding X for the display mode, the parameter is not displayed. Unless stated, all displayed data are for the last run Displayed in Type 4448 Parameter Display Sequence † Default Pro. T Pro. T Battery Status Memory Status Time (current real time) Duration Zpeak Dose % Projected Dose % Dose % Projected Dose % C –...
  • Page 24 Personal Noise Dose Meter Type 4448 – User Manual The default alarm levels will depend on which display mode is selected, either ISO or OSHA mode. The default levels are summarized insection Table 2.3. Table 2.3 Default alarm levels for ISO and OSHA Display Blue LED Off Blue LED Flashing Slow Blue LED Flashing Fast Mode ...

  • Page 25: Chapter 3 Calibration

    Chapter 3 Calibration It is important to calibrate each Type 4448 before and after use, in accordance with workplace noise regulations. For each calibration, Type 4448 records calibration level and time. The last calibration before and the first after a measurement will be attached to each measurement record.
  • Page 26 Personal Noise Dose Meter Type 4448 – User Manual Fig.3.2 Calibrating Type 4448  with Sound Calibrator  Type 4231 4) Turn on the calibrator. Type 4448 automatically recognizes calibration tones and enters calibration mode. If Type 4448 does not recognize the calibration tone, see Table 3.1, below. 5) Press the R pushbutton to confirm that you wish to calibrate. Type 4448 will take a few seconds to automatically adjust to the required level: 94.0 dB.
  • Page 27 CHAPTER 3 Calibration Fig.3.3 Attaching the  windshield 110415 ✔ Best Practice:  Grip the black plastic ring to avoid damaging the windshield foam. ✐ You can remove and attach the windshield while the instrument is on. Please note: Table 3.1 Possible calibration issues Symptom Cause Solution Calibration fails Calibrator automatically switched off prior Restart the calibration sequence to initiate to the start of the calibration sequence Turn on the calibrator after placing it on...
  • Page 28 Personal Noise Dose Meter Type 4448 – User Manual...

  • Page 29: Post-Processing With Protector Type 7825

    Chapter 4 Post‐processing with Protector Type 7825 Installing Protector Type 7825 Protector Type 7825 is required to set up Type 4448 and download data after measurements. To install this software: 1) Insert the software DVD into your PC. If auto-start is enabled a menu should appear. 2) If auto-start is not activated, locate your DVD drive (usually D:\ or E:\) and run the Setup.exe program.
  • Page 30 Personal Noise Dose Meter Type 4448 – User Manual To setup Type 4448 from the PC: 1) Plug the USB end of the IR-to-USB Cable AO-1492 into the PC. The first time you do this drivers must be installed (this might recur every time a different USB socket is used on the PC). The drivers should install automatically.
  • Page 31 CHAPTER 4 Post‐processing with Protector Type 7825 Fig.4.3 Select the 4448 tab  and appropriate COM  port 7) Select Tools > Dose Meter Setup Type 4448. > Fig.4.4 Select 4448 8) Select the tab you wish to set up: – Display: Language: English, French, Spanish, Portuguese, Italian or German Two lines of text to be shown during start up (each line limited to 12 characters) –...

  • Page 32: Transferring Data From Type 4448

    Personal Noise Dose Meter Type 4448 – User Manual Make all adjustments then switch on Type 4448 and place it on the table with the IR sensor face to face with the IR window of the cable (Fig.4.5). Fig.4.5 Type 4448 and IR  sensor positioned for  data transfer 110433 9) Click the Transfer button. During data transfer the blue LED on Type 4448 will flash.
  • Page 33 CHAPTER 4 Post‐processing with Protector Type 7825 7) The next page will show whether a Type 4448 has been successfully identified and indicates how many runs (measurements) are available on the device. Select Clear Memory if you want the runs to be removed from Type 4448 after a successful download. 8) Click Next –...
  • Page 34 Personal Noise Dose Meter Type 4448 – User Manual...

  • Page 35: Chapter 5 Theory

    Chapter 5 Theory Human Hearing Basics The human hearing consists of the outer ear, middle ear and inner ear (see Fig.5.1): • The outer ear collects sound and guides it towards the eardrum, a thin membrane separating the outer from the middle ear •...

  • Page 36: Noise-Induced Hearing Loss

    Personal Noise Dose Meter Type 4448 – User Manual Fig.5.1 Basic view of an  average human ear Hamme Anvil Semicircular Canal Nerve Fibres Cochlea Basilar Membrane Pinna Auditory Canal Ear Drum Round Window Stirrup Eustachian Tube Oval Window Middle Outer Ear Inner Ear When sound arrives at the outer ear it is funnelled towards the eardrum, which in turn is set into motion by the oscillating air pressure.
  • Page 37 CHAPTER 5 Theory Noise-induced hearing loss is a kind of damage that, if observed too late, will be permanent since long-term excessive noise exposure causes damage of the sensory part of the human hearing, the hair cells in the inner ear and – often as a consequence – the acoustic nerve. The inner ear is the most fragile part of our hearing and the part that, at least with our current knowledge and techniques, cannot be repaired.

  • Page 38: Measurements With Noise Dose Meters

    Personal Noise Dose Meter Type 4448 – User Manual • See how people use hearing protection: do they neglect them, are they not properly fit, do glasses and other equipment prevent protectors from proper function, is worn out protection used Observation can also tell whether the background noise levels require shouting to communicate, and how much this may add to noise exposure.
  • Page 39 CHAPTER 5 Theory Both are a measure for the noise exposure but express it in a different way: • The equivalent average sound pressure level represents a constant noise level that – if applied over the same amount of time as the duration of the measurement – would lead to the same exposure as the varying noise level of the actual working process •...

  • Page 40: The Importance Of Peak Levels

    Personal Noise Dose Meter Type 4448 – User Manual The relation between time and level is called the Exchange Rate. The relevant ISO standards, referred to by the EU directive for analysis and measurement, use an energy-based average for the noise dose calculation, which means that the exchange rate or amount of increase that corresponds to a doubling of the noise dose is 3 dB.
  • Page 41 CHAPTER 5 Theory Task‐based Approach If observation shows that the day and processes can be clearly split into distinguished tasks, it is recommended to assess them separately and find the average noise level for each individual task. The full workday is then modelled by combining these levels with the individual task durations determined by observation and with interviews.

  • Page 42: Which Approach To Choose

    Personal Noise Dose Meter Type 4448 – User Manual If the expanded uncertainty is larger than 6 dB more random samples need to be taken. Table 5.3 Group (G) Size Minimum Measurement Time Measurement  G ≤ 5 Min T = 5 hr time samples  meas,tot according to  5 < G ≤ 15 Min T = 5 hr + (G –...

  • Page 43: Things To Keep In Mind When Doing Dose Meter Measurements

    CHAPTER 5 Theory 5.3.5 Things to Keep in Mind when Doing Dose Meter Measurements Whatever your approach will be, proper dose meter positioning is of great importance for the validity of measured data. Today, most standards require the dose meter to be positioned on the subject's shoulder, about 10 – 15 cm from the most exposed ear and at a height of approximately 4 cm above the shoulder.

  • Page 44: Next Steps

    Personal Noise Dose Meter Type 4448 – User Manual For example, if the measured from Type 4448 was 102 dB, and using the value for SNR in the example above: at the ear = 102 – 28 = 74 dB(A) The HML method is a more effective method of calculating the effectiveness of hearing protection because it takes into account the frequency component of the noise.

  • Page 45: Chapter 6 Specifications

    Chapter 6 Specifications STANDARDS STABILIZATION TIME All types conform with the following National and  3 seconds after start International Standards: EXCHANGE RATE • IEC 61252:2002 Q=3 dB and Q=5 dB  • ANSI S1.25:1991 Intrinsically safe versions also conform to:  UNDERRANGE • ATEX EEx ia I M1, EEx ia IIC T2 II 1 G, certificate number  1 dB below measurement range 07ATEX2032X OVERLOAD INDICATION • FM/CSA approvals are to Class 1, Division 1, Groups A, B C,  RMS: at 140.4dB (0.1dB above measurement range) D, temperature classification T2 Peak: at 143.4dB linear (0.1dB above peak range) SUPPLIED MICROPHONE Indicated in display during measurement and on PC in  Type: 1/2 Condenser Microphone mounted on instrument  downloaded data body THRESHOLD AND CRITERION LEVELS FREQUENCY WEIGHTINGS Type 4448 displays OSHA data for 80 and/or 90 dB   and RMS Detector: A (and simultaneously C) thresholds and a 90 dB criterion level. After download to PC,  Peak Detector: A, C and Z (Linear) data can be recalculated with the following levels: •...
  • Page 46 Personal Noise Dose Meter Type 4448 – User Manual SETUP BATTERY All parameters are always measured simultaneously Internal Rechargeable NiMH Cells: recharge using charger  On Instrument:  (ZG‐0860) Contrast (6 steps) Battery Operating Time: 28 hr Language (see above) Battery Status Indication: Symbol and estimated remaining  Auto  (Auto‐lock pushbuttons Yes/No) time (hr) Display mode (ISO/OSHA), Pro. Mode (Yes/No) Time to Fully Charge: 90 min max. Alarms (Activate/Deactivate LED dB Alarm function) Battery Replacement: Requires authorized service Preset time (No or up to 12 hours in 30 min steps) MEASUREMENT CONTROL Clear Memory Manual Control Mode: Use pushbuttons for Start/Stop Using PC: Language, welcome screen text, display mode, LED  Preset  M easurement Time Activated:  M easurement  s tarted  Alarms, calibration target level, time and date, preset  manually. Unit will automatically stop measurement and  measurement time (1‐minute steps) auto‐lock turn off at preset time Pro. Mode: Threshold and criteria levels ENVIRONMENTAL CONDITIONS PRESET MEASUREMENT TIME...
  • Page 47 CHAPTER 6 Specifications Ordering Information KITS WITH TYPE 4231 INCLUDED HML Noise Dose Meter Type 4448‐C‐001 Kits: Type 4448‐001 Personal Noise Dose Meter with HML  Type 4448‐C‐101 Starter kit with 1 Type 4448‐001 unit  parameters and Sound Calibrator Type 4231 Type 4448‐002 Personal Noise Dose Meter with HML  Type 4448‐C‐103 Starter kit with 3 Type 4448‐001 units  parameters, Intrinsically Safe Model and Sound Calibrator Type 4231 STARTER KITS Type 4448‐C‐105 Starter kit with 5 Type 4448‐001 units  HML Noise Dose Meter Type 4448‐001 Kits: and Sound Calibrator Type 4231 Type 4448‐101 Starter kit with 1  Type 4448‐001 Type 4448‐C‐110 Starter kit with 10 Type 4448‐001 units  Type 4448‐103 Starter kit with 3  Type 4448‐001 and Sound Calibrator Type 4231...
  • Page 48 Personal Noise Dose Meter Type 4448 – User Manual Compliance with Standards The CE marking is the manufacturer's declaration that the product meets the requirements of the  applicable EU directives RCM mark indicates compliance with applicable ACMA technical standards – that is, for  telecommunications, radio communications, EMC and EME China RoHS mark indicates compliance with administrative measures on the control of pollution  caused by electronic information products according to the Ministry of Information Industries of  the People’s Republic of China WEEE mark indicates compliance with the EU WEEE Directive Safety ATEX Directive 94/9/EC and the following intrinsic safety standards: EN 60079–0: 2009,  EN 60079–11: 2007 and EN 60079–26: 2006. EN 60950: Safety of IT Equipment. EN 60335–2–29: Safety of Electrical Appliances. EMC Emission IEC 61000–4–3/6–3: Test techniques and requirements for Radiated Electromagnetic  compatibility (EMC) field tests. EMC Immunity IEC 61000–4–6/6–2: Test techniques and requirements for Immunity to Electromagnetic  compatibility (EMC) – disturbances induced by radio frequency fields. Tested at 10 V/m or greater. IEC 61000–4–2: Test techniques and requirements for Electrostatic discharge immunity tests. Product Specific  IEC 61252: 2002: Electro‐acoustics – Specifications for Personal Sound Exposure Meters. Standards ANSI S1.25: 1991: Specifications for Personal Noise Dosimeters.

  • Page 49: Appendix A Glossary

    Appendix A Glossary Frequency weighting corresponding approximately to the 40 dB equal loudness A-weighting filter: curve, that is to say, the human ear’s response at low to medium sound levels. It is by far the most commonly applied frequency weighting and is used for all levels of sound.
  • Page 50 Personal Noise Dose Meter Type 4448 – User Manual Our hearing covers a surprisingly wide range of sound pressures – a ratio of over a million to one. The dB scale makes the numbers manageable The Noise Dose is the equivalent averaged A-weighted Noise Level (taking the Dose, ProjDose: Threshold Level into account) using Exchange Rate = 3 for an 8 hour period (reference duration) relative to the maximum allowed (the Criterion Level) –...
  • Page 51 Glossary The Noise Dose is the averaged A-weighted Noise Level (taking the Threshold DoseUQ, ProjDoseUQ: Level into account) with Time Weighting U = F or S and Exchange Rate Q = 4, 5 or 6 for an 8 hour period (reference duration) relative to the maximum allowed (the Criterion Level) –...
  • Page 52 Personal Noise Dose Meter Type 4448 – User Manual A ‘C-weighting’ curve is also used, particularly when evaluating very loud or low- Frequency weighting frequency sounds. (cont.): L p (dB) –20 –40 –60 Frequency (Hz) 100 200 500 10k 20k 000055 Sound Exposure Level – sometimes abbreviated SEL and sometimes called Single Event Level, is the Sound Exposure expressed as a level.
  • Page 53 Glossary The noise level exceeded for 90% of the measurement period with A-frequency AF90.0 weighting and Fast time weighting. The level is based on statistical analysis of a parameter (LAF or LAS) sampled at 10 ms intervals into 0.2 dB wide classes. The percentage is user-definable.
  • Page 54 Personal Noise Dose Meter Type 4448 – User Manual The Daily Noise Exposure Level for a user-defined reference period. L ep,d,v ep,d,v: calculated from the measured L and the settings of Exposure Time and Reference Time. Used, for example, for calculating a Weekly Noise Exposure Level, by setting the Reference Time to 40 h.
  • Page 55 Glossary Any sound levels below the threshold level do not contribute to the Dose Threshold Level: measurement data. For example, if you set the threshold level to 80, any sound levels below 80 dB are not taking into consideration by the instrument, when it calculates doses and time weighted averages.
  • Page 56 Personal Noise Dose Meter Type 4448 – User Manual...

  • Page 57: Index

    Index Symbols COM port  ............22, 24 Configuration #CPeaks(>140dB) ........... 46 On Instrument  ..........10 Criterion Level  ............41 Numerics C‐weighting filter  ...........41 3‐way Charger ........3, 4, 7, 8, 9, 39 Decibel (dB) ............41 Action Value ......... 29, 31, 45, 46 Display .......... 2, 4, 10, 13, 23, 37 Alarm Settings  ............15 Display Mode  ......... 10, 14, 15, 16, 38 ANSI  ............. 2, 37, 40 Dose  ...............42 S1.25 1991  ..........37, 40 DoseUQ  ..............43 ATEX ............. 3, 37, 40 Download ........2, 11, 12, 25, 37, 38 A‐weighting filter ...........
  • Page 58 Infrared  ...........2, 3, 4, 21, 22, 24 Making a Measurement  .........12 Sensor  ........... 4, 21, 24 Memory  ..... 2, 10, 11, 12, 13, 14, 15, 25, 37, 38 Initial Setup  ............. 7 Clear  ............11, 25 Instrument ............... 4 Status ..........10, 13, 14, 15 Instrument and Kit Components  ......3 Microphone .1, 2, 3, 11, 12, 13, 17, 19, 21, 32, 37, 38 Intrinsically Safe ........... 2, 37, 39 Mounting  ......1, 2, 3, 7, 11, 12, 35, 39 IR‐to‐USB Cable  ............. 22 ISO  ..2, 10, 14, 16, 23, 30, 32, 33, 34, 37, 38, 45 9612‐2009 ....... 33, 34, 37, 38, 45 Noise Exposure  .. 1, 15, 29, 30, 31, 33, 34, 36, 45, 47 Noise Reduction Rating ........2, 35 Noise‐induced Hearing Loss ........28 Job‐based Approach ...
  • Page 59 Single Number Rating ........2, 35, 36 Task‐based Approach  ..........33 Sound ..............46  ..............46 Cpeak Sound Level  ............46 Threshold Level  ............47 Sound Pressure Level ..........46 Time and Date  ........7, 10, 11, 38 Stand‐by  ..........10, 11, 14, 37 Time Weightings .............43 Start a Measurement ..........12 Transfer Button  ............24 Status ........2, 4, 8, 10, 12, 13, 14, 15 TWA ..........31, 32, 37, 43, 47 Stop a Measurement  ..........13 TWAv  ..............47 Switch On and Off ..........10   ..............47 Windshield  ....2, 4, 11, 12, 17, 18, 19, 38, 39 Workday‐based Approach ...
  • Page 64 © Brüel & Kjær. All rights reserved.  www.bksv.com...

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