Noise at Workplace

1
Noise at Workplace

• Dr. Noor Hassim Ismail

2
Anatomy of Ear

• 3 parts
• Outer ear
• Middle ear
• Inner ear
• Cochlea- hearing apparatus
• Vestibular- balancing of the body

3
Pathophysiology of hearing

• How we hear?
• Air conduction
• Bone conduction.
• Conductive hearing loss
• Sensorineural hearing loss

4
Effects of noise

• Noise definition- unwanted sound.
• Noise unit- intensity decibel (dB),
  frequency(hertz hz).
• Type of sound based on frequency
• Infrasonic (0-20 Hz) ,
• Audible (20-16,000)
• Ultrasonic (gt 16,000)

5
Factors contributing to noise hazard

• Noise spectrum
• Overall noise exposure
• Duration of exposure
• Individual susceptibility.

6
Type of noise

• Steady state noise
• Intermitent noise
• Fluctuation noise
• Impulse noise

7
Effect of noise

• Noise induced hearing loss
• Temporary
• permanent
• Rupture of ear drum
• Dislocation os ossicle
• Speech interference
• Annoyance

• Other effect
• Task performances
• Intrusion of privacy
• tinnitus
• Blood pressure
• Fatique
• Bood sugar
• Gastric acid secretions

8

• Intermittent noise
• Less effect than steady state noise

• Impulse noise
• Effect depend on number of impulse exposed.

9
Hearing Conservation Programme

• Indication s for the ed of a HCP
• Difficulty in communication
• Tinnitus after workking
• Temporay losss of hearing

10
Elements of HCP

• Assessment of noise exposure
• Noise control
• Audiometric testing programme
• Medical evaluation and treatment
• Health education and training
• Provision of hearing protection
• Establishment of proper record keeping.

11
Assessment of noise

• Competent person
• To know the noise level
• Mapping the noise level
• gt85 dB (action level) do HCP
• lt 85 dB no HCP

12
Noise Control

• Nose reduction activities to less than 85 dB
• Engineering control
• Administrative control
• Both methods
• Control strategies
• Sources
• At path
• Receiver

13
Education programme

• To educate the workers
• Training every 2 years
• Teach them
• Effect of noise
• Control
• Personel protective equipment and maintenance
• Audiomeric test
• Noise regulations
• etc

14
Audiomeric testing programme

• Baseline audiometric test
• Periodic audiometric test
• Objective the test
• To establish the hearing status.
• To monitor hearing loss during period of
  employement
• To identify worker who is secceptible to noise
• To regulate noise hearing programme

15
Medical Evaluation and treatment

• Abnormal audiogram refer to doctor
• Hearing problems refer to doctor

16
Povision of hearing protectors

• Ear plugs
• Ear muffs
• Factors deciding type of PPE.
• Sound reduction properties
• Comfort of worker
• Cost
• Approved by DOSH.

17
Record Keeping

• Name
• Job
• Location of employee
• Base line audiogram
• Occupational history
• Medical examination

• Keep record for 5years after stop work.