IAQ and Noise tools. Masood Ahmed MS, CIH, CRSP Occupational Hygienist OHCOW South Central/Hamilton

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2 IAQ and Noise tools Masood Ahmed MS, CIH, CRSP Occupational Hygienist OHCOW South Central/Hamilton

3 Disclaimer. The purpose of this presentation is to provide information and education about noise. This presentation should not be used for training or certification purposes.

4 Occupational Health Clinics for Ontario Workers (OHCOW) An inter-disciplinary occupational health team: occupational physicians occupational health nurses ergonomists occupational hygienists customer service coordinators leadership/administration Funded by MoL Prevention Services (from compensation premiums) BoD majority from organized labour

5 Regional Clinics:

6 Services: 1. Medical diagnostic service for workers who may have work-related health problems. 2. Group service providing educational and investigative support for joint health and safety committees and workplace parties. 3. Inquiry service to answer workplace health and safety questions. 4. Outreach and education service to make people aware of health and safety issues and promote prevention. 5. Research service to identify, investigate and report on illness, injury & disease trends.

7 1. Physics 2. Health effects 3. Regulations 4. Measuring noise 5. Noise control Overview: 6. Other noise issues 7. Noise apps and tools

8 A little noise physics: Speed of Sound feet per sec at room temp (or 750 mph or 1200 km/hr). As frequency (pitch) goes higher, the wavelength gets smaller (more cycles per second). - at 100 hertz (Hz) the wavelength is ~ 10 feet - at 1000 hertz the wavelength is ~ 1 foot - at 10,000 hertz (10 khz) wavelength is ~ 1 inch Human audible range 20 Hz to 20,000 Hz

9 obligatory frequency diagram: One wave is a complete cycle, the number of cycles (waves) per second is the frequency exit to frequency audio file

10 20 Hz 20,000 Hz

11 Octave bands (Hertz)

12 Decibels (db)

13 obligatory diagram of the ear:

14 .what we re trying to prevent normal hearing cells damaged hearing cells

15 How it is measured?

16 hearing threshold (db) progression of NIHL (noise induced hearing loss) Hz 500Hz 1000Hz frequency 2000Hz 3000Hz 4000Hz 6000Hz 8000Hz m n p d t f s th a o i ee sh 60 pre-employment: worker starting first job

17 hearing threshold (db) progression of NIHL (noise induced hearing loss) Hz 500Hz 1000Hz frequency 2000Hz 3000Hz 4000Hz 6000Hz 8000Hz m n p d t f s th a o i ee sh 60 after 3-5 yrs exposure

18 hearing threshold (db) progression of NIHL (noise induced hearing loss) Hz 500Hz 1000Hz frequency 2000Hz 3000Hz 4000Hz 6000Hz 8000Hz m n p d t f s th a o i ee sh 60 after yrs exposure

19 hearing threshold (db) progression of NIHL (noise induced hearing loss) Hz 500Hz 1000Hz frequency 2000Hz 3000Hz 4000Hz 6000Hz 8000Hz m n p d t f s th a o i ee sh 60 after yrs exposure

20 What are the chances? depends on the intensity of the noise (how loud it is measured in decibels (dba)) depends on the frequency high pitch (treble) sounds more damaging than low (bass) sounds depends on the length of time exposed (yrs) depends on the age (natural hearing loss due to age - presbycusis)

21 hearing threshold (db) presbycusis (age hearing loss) Hz 500Hz 1000Hz frequency 2000Hz 3000Hz 4000Hz 6000Hz 8000Hz u m n p d t f s th a o i ee sh 60

22 hearing threshold (db) presbycusis (age hearing loss) Hz 500Hz 1000Hz frequency 2000Hz 3000Hz 4000Hz 6000Hz 8000Hz u m n p d t f s th a o i ee sh 60

23 High frequency loss happens first

24 stats last five years, the annual costs for noise induced hearing loss claims for all sectors in Ontario exceeded $50 million per year, (MOL 2014) the WSIB showed a steady increase in NIHL registered claims from 3653 claims in 2005 to 5416 claims in 2009 (WSIB, 2011) Masterson et al. (2013) found 18% of 1,122,722 worker audiograms collected from the NIOSH OHL Surveillance Project met the NIOSH criteria for NIHL Stekelenburg (1982) noted that: even if 80 dba is taken as a time weighted average limit 10% of the exposed population will not be protected against impaired social hearing caused by noise. (page 408)

25 exit to Hearing Loss Simulator

26 What are the symptoms of NIHL (noiseinduced hearing loss)? usually gradual (not noticeable) but can be immediate (if close to an explosive noise) tinnitus ringing, buzzing, or roaring in the ears or head can be intermittent or continuous extremely annoying and not curable screening questions handout

27 How Much Noise is too Much? Anything above 65 dba will eventually wear down your hearing. Years of exposure above dba will lead to a percentage of workers with a hearing disability (legally deaf). Trying to carry on a conversation over the phone with a background noise level of dba is very stressful.

28 Noise: Ontario OEL = 85 dba ACGIH TLV = 85 dba

29 Noise Induced Hearing Loss: WSIB recognizes noise-induced hearing loss (NIHL) compensation after an exposure of 90 dba for 8 hrs/day for a minimum of 5 years or equivalent noise exposure; the policy also lists equivalent exposures as 84 dba for 40 yrs or 28 yrs at 85 dba Tinnitus is also compensable Allowed NIHL Two or more years of sever tinnitus Diagnosed by a specialist

30 WSIB Hearing Loss Exposure Equivalencies The minimum hazardous noise exposure of 90 db(a) for 8 hours per day for 5 years has the following equivalencies*: 84 db(a) for 40 yrs 89 db(a) for 7 yrs 85 db(a) for 28 yrs 91 db(a) for 3.5 yrs 86 db(a) for 20 yrs 92 db(a) for 2.5 yrs 87 db(a) for 14 yrs 93 db(a) for 1.8 yrs 88 db(a) for 10 yrs 94 db(a) for 1.25 yrs * ISO Acoustics Determination of occupational noise exposure and estimation of noise-induced impairment. Internat. Standard ISO nd ed. Geneva, NIHL does not normally develop in less than 1.25 years.

31 Other than hearing loss health effects: what the non-auditory effects of noise are is still not certain. In general, the suspected effects include: cardiovascular function (hypertension, changes to blood pressure and/or heart rate), changes in breathing, annoyance, sleeping problems, physical health and mental health. This wide range of effects has led researchers to believe that noise has the ability to act as a general, non-specific stressor.

32 Vocal Cord Nodules

33 How is noise regulated in Ontario?

34 Noise Legislation: O.Reg. Regulation 851, section 139 employers take all measures reasonably necessary in the circumstances to protect workers from exposure to hazardous sound levels. protective measures against noise exposure include engineering controls, work practices and personal protective equipment. assessment of noise levels shall be done without regard to any use of personal protective equipment. every employer shall ensure that no worker is exposed to a sound level greater than an equivalent sound exposure level of 85 dba, L ex,8.

35 O.Reg. 851 s.139 (continued) the employer shall protect workers from exposure to a sound level greater than 85 dba, L ex,8 without requiring the use of personal protective equipment. personal protective equipment is only to be used if engineering controls, a) do not existence or are not obtainable; b) are not reasonable or not practical to adopt, install or provide because of the duration or frequency of the exposures or because of the nature of the process, operation or work; c) are rendered ineffective because of a temporary breakdown of such controls; or d) are ineffective to prevent, control or limit exposure because of an emergency.

36 O.Reg. 851 s.139 (continued) if engineering controls can t be used then workers shall wear and use personal protective equipment appropriate in the circumstances to protect them from exposure to a sound level greater than 85 dba, L ex,8 a clearly visible warning sign shall be posted at every approach to an area in the workplace where the sound level regularly exceeds 85 dba. An employer who provides a worker with a hearing protection device shall also provide adequate training and instruction to the worker in the care and use of the device, including its limitations, proper fitting, inspection and maintenance and, if applicable, the cleaning and disinfection of the device.

37 Ontario Regulation 381/15 New noise regulation, essentially the same as O.Reg. 851 s.139 except that it covers all workers in the province (not just those covered by the industrial regs (O.Reg. 851))

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39 previous table: current table: Column 1 Column 2 Sound Level in Decibels Duration Hours per 24 hour day ½ ½ 115 ¼ or less Over 115 No exposure

40 Measuring noise: no measurement everyone agrees its too noisy and let s do something about it voice effort scale do you have to raise your voice at an arm s length away if so probably over dba $ type III sound meter (lots online) can work well for area measurements (but no guarantee calibration needed) dosimeter $ , does datalogging and acts as a sound level meter (usually downloadable) measure individual exposures averaging over time octave band analyzer $ ,000, gives you noise frequency analysis usually used for acoustics and noise control engineering

41 Voice effort noise assessment: voice level: (1 meter away) normal loud very loud shouting maximum shouting noise level: (in db(a)) perception: hazard level: slight distraction annoying, unpleasant some risk of hearing loss medium risk of hearing loss high risk of hearing loss

42 Noise Measurement

43 There s an App for that! NIOSH has reviewed various noise measurement apps and found that some do a reasonable job of measuring sound (and some not so reasonable) SPLnFFT

44 Noise Map

45 What next after measuring?

46 Prevention Opportunities Best Good Temporary check on effectiveness of controls source > path > exposure > target > disease too late!!

47 effectiveness of hearing protectors

48 effectiveness of hearing protectors

49 effectiveness of hearing protectors

50 This is not the permanent solution! nor even a very effective temporary one.

51 Preventing noise purchasing policy (new machinery <75 dba) vibration control (isolators, damping) quiet materials for conveyors, bins (noiseless steel, plastic coatings, etc.) silencers, mufflers, specially designed compressed air nozzles balancing rotating parts, avoiding harmonic frequencies, etc. avoiding impacts in process flow (slide instead of drop) enclosures, barriers, curtains sound absorbing acoustic wall/ceiling treatment increasing distance from source OHCOW worksheet Doing something about noise

52 Noise control principles & examples

53 Buy Quiet To buy quiet in today s market purchasers need a high level of understanding of noise and noise control and must have a high degree of determination to achieve noise control in their workplace. Purchasers who successfully buy quiet seek out quieter machines and critically review the noise information supplied with them, which is often flawed. Such purchasers sometimes need to write, and check conformity with, their own specification for noise. Brereton & Patel, Buy Quiet as a Means of Reducing Workplace Noise, Acoust Aust DOI /s x, online Mar 29,2016

54 Quiet air guns

55 Compressed air nozzles & exhaust silencers

56 Tool Redesign Using a jacket over the tubular outlet in the jacket, the high frequency noise given off by a jack hammer can be partially shielded. The low frequency noise in the exhaust air is effectively reduced. The enlarged sections are between the barrel and the jacket functions as an expansion chamber.

57 Simple Noise Reduction

58 Vibration Transmission

59 Vibration & Damping

60 Vibration Transmission

61 Vibration Isolation

62 Vibration isolators are made of various materials

63 Vibration Damping Coatings or line metal conveyors with old rubber conveyor belts

64 Noiseless Steel

65 Surface area transmission

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67 Enclosure

68 Noise Barriers & Enclosures

69 Enclosure of Electric Motor or Compressor

70 Effects of Openings in Enclosures (hypothetical) Degree of enclosure decibel reduction full enclosure 60 db 0.1% open 30 db 1% open 20 db 5% open 13 db 10% open 10 db 30% open 5 db 50% open 3 db

71 Noise Absorbing Baffles

72 Barriers to Prevention: Complacency: it s always been that way, things will never change Expertise: we need an expert with one of those fancy noise meters to come in and measure the noise Expense: noise control is just too expensive! Shift the Blame: they should have worn their ear plugs

73 Hearing Conservation Program 1. Noise surveys and data analysis 2. Education and motivation 3. Noise control 4. Hearing protection devices 5. Audiometric monitoring The Noise Manual 5 th Edition

74 What about office noise? Background office noise usually comes from the ventilation system and is usually measured in an unoccupied office (or when things are quiet if occupied) The American Society of Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE) has developed standards for background noise due to ventilation system to ensure adequate conditions for concentration and communication

75 Design Guidelines for HVAC-related Background Sound 2011 ASHRAE Handbook HVAC Applications (SI) Table 1 page 48.3 open-plan offices: Room Criteria (RC): RC 40 (equivalent to 45 dba) private offices: Room Criteria (RC): RC 30 (equivalent to 35 dba) Quality-Assessment Index (QAI): QAI 5 db (N) N= neutral (balanced sound spectrum) LF= rumble (low frequency dominant) LFV B = rumble (low frequency with moderately perceptible vibration) LFV A = rumble (low frequency with clearly perceptible vibration) MF= roar (mid-frequency dominant) HF= hiss (high-frequency dominant)

76 Cost-effective Open Plan Environments (COPE project) The National Research Council Canada (NRCC) has developed standards for open plan office environments (COPE) For noise the COPE recommendations are: Ensure that all noise sources (e.g., ventilation systems, office equipment and water coolers) do not exceed 40 dba. The COPE research finding identified the optimum noise level (background & foreground) for open plan offices was determined to be between dba

77 Acoustics RevMeter Pro an app to estimate the reverberation time in a room ( $7) ANSI S Acoustical Performance Criteria, Design Requirements, and Guidelines for Schools Unoccupied classroom levels must not exceed 35 dba The signal-to-noise ratio should be at least +15 db Unoccupied classroom reverberation must not surpass 0.6 seconds in smaller classrooms or 0.7 seconds in larger rooms

78 Noise Tools/Apps

79 Noise Legislation: O.Reg. 381/15 employers take all measures reasonably necessary in the circumstances to protect workers from exposure to hazardous sound levels. protective measures against noise exposure include engineering controls, work practices and personal protective equipment. assessment of noise levels shall be done without regard to any use of personal protective equipment. every employer shall ensure that no worker is exposed to a sound level greater than an equivalent sound exposure level of 85 dba, L ex,8.

80 solution: on-line calculator

81 Sound Level Duration (85 dba L ex,8 ) Duration (80 dba L ex,8 ) (in db(a)) (hrs/24 hr day) (hrs/24 hr day) 80¼ 24 7½ 81½ 18 5⅔ ¼ 12 3¾ ¼ ½ 86¼ ¼ 89¼ min 92¼ 1½ 30 min min min 10 min min 5 min 101¾ 10 min 3 min 104¾ 5 min 1½ min 111¾ 1 min 20 sec 114¾ 30 sec 10 sec

82 Time Weighted Average Calculator: This table calculates the 8 hr equivalent sound exposure level for different noise levels and for specified lengths of exposure time. To use this chart, enter the amount of time spent performing each activity and the corresponding noise level. Exposure Time (hrs) (min) Activity 1 45 Activity Activity Activity 4 2 Activity Activity 6 35 Activity 7 5 Activity 8 Activity 9 Activity 10 Activity 11 Activity 12 Activity 13 Activity 14 Activity 15 Activity 16 Activity 17 Activity 18 Activity 19 Activity 20 Activity 21 Activity 22 Activity 23 Activity 24 Activity 25 Total Time Noise Level (dba) Equivalent Noise Exposure Level 86.2 Dose (%) 14.9% 46.1% 27.6% 7.9% 2.0% 0.6% 32.9% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% Total Dose 132.0%

83 Who can measure? Noise Apps Measure-Decibels-Step-2.jpg

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87 SPLnFFT

88 SoundMeter App

89 app to measure reverberation RevMeter Pro an app to estimate the reverberation time in a room ( $7) ANSI S Acoustical Performance Criteria, Design Requirements, and Guidelines for Schools Unoccupied classroom levels must not exceed 35 dba The signal-to-noise ratio should be at least +15 db Unoccupied classroom reverberation must not surpass 0.6 seconds in smaller classrooms or 0.7 seconds in larger rooms

90 whole body vibration app free app which measures whole body vibration (WBV) well researched with published study to show validity i-tunes store search for WBV

91 Online Audiometric test:

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93 Questions?