Occupational Health & Safety

1. LSEEE101A 9119A Occupational Health & Safety Physical & Electrical

2. Physical Hazards • Noise • Radiation • Light • Vibration These are

3. Occupational Health & Safety LSEEE101A 9119A Noise

4. Noise A travelling wave of pressure These vibrations can travel through What is it? • Solids • Liquids • Gases Known as a medium

5. Noise • Solids • Liquids • Gases Both longitudinal and transverse waves Longitudinal waves Sound cannot travel through vacuum How does it travel through?

6. Noise What is it characteristics? • Amplitude • Frequency • Speed Volume Pitch How fast it travels For humans  12 Hz and 20 kHz Upper limit generally decreases with age

7. Speed The speed of sound depends on the medium through which the waves are passing 20 °C air at the sea level • Air • Fresh Water • Steel 343 ms-1,1 230 km/h, 767 mph 20 °C 1,482 ms-1, 5 335 km/h, 3315 mph 5,960 ms-1, 21 460 km/h, 13 330 mph The speed is dependant on the mediums: • Density • Temperature  Density  Speed  Temperature

8. Noise How do we Measure it? Sound Pressure in Pascals p Sound Pressure Level in decibels dB Lp or SPL dB = 2 x 10-5 Pa But what about frequency

9. How Do We Hear Outer Ear Pinna or Auricle Gathers sound from the surrounding environment and sends it down the ear canal.

10. How Do We Hear Middle Ear • Tympanic membrane (eardrum) • 3 small bones • Malleus • Incus • Stapes carry sound to the inner ear

11. How Do We Hear Inner Ear Made-up of two main parts: • Vestibular system • Cochlea Responsible for balance Made up of a system of complex hair cells (sensory cells) send impulses to the auditory nerve

12. Frequency The human ear does not hear frequencies equally The higher the frequency the less sensitive the ear is Measurement equipment has to be filtered to adjust noise levels to match the human ear

13. Frequency “D” Curve “C” Curve “B” Curve “A” Curve

14. Noise • Tension Headache • Sleeplessness • Irritability • Nervousness • Increase In Blood Pressure • Increase In Stomach Acid Level • Inability To Concentrate • These are generally considered short term. • Not considered permanent. Excessive noise has various effects on people. Examples are:

15. Noise • What are they? • What noise level is considered dangerous? • How long must you be exposed before long term damage is done? • What is the maximum peak noise level that any worker be exposed to? Assignment Question Excessive noise has various long term effects on people.

16. Noise If workers are stationary and noise is constant Basic sound level meter What type of filtering must it have? • Placed at the operator’s ear level • Also record the length of time the person is exposed to that noise How do we measure it?

17. Noise If workers are stationary and noise peaks Basic sound level meter What type of filtering must it have? What is the maximum level? Very loud noise • Gun fire • Jet engines • Nail guns How do we measure it?

18. Noise If workers move around or the noise level varies Personal Noise Exposure Meter Records and calculates noise exposure with regard to: • Frequency • Level • Length of time How do we measure it?

19. Noise

20. Occupational Health & Safety LSEEE101A 9119A Radiation

21. Radiation Two basic types • Ionizing radiation • Non-ionizing radiation Visible light is a form of radiation

22. Radiation Ionizing radiation Alpha Radiation Beta Radiation Gamma and X Radiation A heavy, ejected helium nucleus Particle Radiation A light, ejected electron Electromagnetic Radiation

23. Ionizing radiation Ionizing radiation

24. Radiation Ionizing radiation Alpha Radiation Beta Radiation Gamma and X Radiation • Not able to penetrate human skin • Harmful if the materials are inhaled, swallowed, or absorbed through open wounds Penetrate human skin to the "germinal layer," Penetrate several inches into human skin

25. Ionizing Radiation Disruptive to biological systems, and can cause: • Mutations • Cancer • Cataracts • Radiation sickness • Radiation burns Chronic Effects Acute Effects

26. Ionizing Radiation Parts of the body that are affected: Most Sensitive Least sensitive Blood-forming organs Reproductive organs Skin Bone and teeth Muscle Nervous system

27. Ionizing radiation Non-ionizing radiation Ionizing radiation

28. Non- Ionizing Radiation Low energy form of radiation Broken down into sections • Radio waves • Micro waves • Infrared light • Visible light • Ultraviolet light Cell damage due to heating effect Visible-light lasers damage the retina of the eyes • Burns to skin • Cataracts to the eyes • Skin cancer

29. Occupational Health & Safety LSEEE101A 9119A Lighting

30. Lighting • Clause 46 of the OHS Regulation 2001 states that employers must: • Provide adequate lighting to allow workers to work safely, move safely, and enter and exit the workplace safely (including from emergency exits) • Ensure that there is not excessive glare or reflection • Ensure that lighting allows persons who are not workers to move safely within the place of work.

31. Lighting Provide adequate lighting to allow workers to work safely, move safely AS/NZS 1680 series of standards provides lighting levels for specific industries Enter and exit the workplace safely (including from emergency exits) AS 2293 series of standards provides lighting levels for Emergency lighting

32. LSEEE101A 9119A Occupational Health & Safety Vibration

33. Vibration Vibrations are mechanical oscillations, produced by regular or irregular period movements of a member or body about its rest position Vibration can be a source problems at an engineering level, causing: • Damage to equipment • Loss of control of equipment • Reduced efficiency of machines

34. Vibration The effect of vibration on people. Factors include: • Point of application of the vibration • Frequency of the vibration • Acceleration of the vibration • Duration of the vibration

35. Vibration The body of a sitting person responds to vertical vibration as follows: • 3- 4 Hz ....Strong resonance in the cervical vertebrae • 4Hz.........Peak of resonance in the lumber vertebrae • 5 Hz........High resonance in the shoulder girdle • 20-30 Hz....High resonance between the head and shoulders • 60-90 Hz....Resonance in the eyeballs • 100-200 Hz..Resonance in the lower jaw Musculoskeletal system (muscles, tendons and bones) can "be a path" for vibration and actually amplify the vibration as it moves through the body

36. Vibration Is measured in three distinct patterns or ranges • Low Frequency • Middle Frequency • High Frequency zero to 2 Hz 2 to 15-20 Hz greater than 20 Hz Cumulative Damage Acute Damage

37. Vibration Can affect: • Vision • Muscles • Concentration • Cardiac rhythm Can cause: • Nausea • Hyperventilation • Raised blood pressure • Increased energy dissipation leading to exhaustion

38. Vibration Can cause long term disorders such as: • Raynaud's Syndrome • Hand-Arm Vibration Syndrome • Carpal Tunnel Syndrome • Tendonitis • Various bone and joint disorders

39. Vibration Reduction or Control Source Path Receiver • Reduce vibration intensity/ avoid resonances • Regulate tool speed/ tool balancing • Careful tool selection • Limit exposure time • Rotate personnel • Provide rest periods/ minimize weight and • Use balancers • Reduce vibration transmission • Use vibration isolators/ adapt posture • Reduce grip and push forces/ reduce contact area

40. Vibration Reduction or Control Anti-vibration gloves has been the most prevalent preventive measure taken by some industries Are only effective in the high frequency ranges Most anti-vibration gloves actually amplify vibrations below 75 Hz while dampening the higher frequencies Most handle wraps or foam have this same effect

41. LSEEE101A 9119A Occupational Health & Safety Electricity

42. In NSW there are 12 fatalities per year due to electrocution • What effect has electricity has on the human body • The factors that affect the severity of electric shock • Equipment designed to reduce the possibility of electric shock • Work methods around electrical equipment. • First aid after electric shock

43. How does the human body move?

44. Electricity sees you as a piece of meat

45. What affects the severity of electric shock? • Time • Current • Path The longer, the more damage The greater the current, the greater the heat Does the current go through major organs? • Heart • Lungs

46. Time & Current Graph For Humans • Time in milliseconds • Current passing through the body in mA Measured in: See AS/NZS 60479.1

47. Zone 1 Usually No Reaction

48. Zone 2 Usually no harmful Physiological effects

49. Zone 3 Usually no organic damage Muscular Contractions Difficulty breathing Possibility of Cardiac Arrest

50. Zone 4 Includes Zone 3