Haematology

1. PHYSICAL AGENTS

2. Objectives:
 To know the definition of physical agents
 To identify the physical agents as risk factors in the work and work
environment
 To explain the main effects of physical hazards on health
 To know, roughly, the threshold values of physical hazards
 To recognize the main occupational diseases because of physical hazards
exposure and to know when to refer the patient to an occupational physician
 To explain the specific role, tasks and responsibilities of the occupational
health services and occupational physician at the workplaces with physical
hazards exposure (prevention, treatment)

3. Which are the physical agents?
 Noise
 Vibrations
 Radiations
 Temperature
 Lighting
 Pressure

4. Which are the main characteristics?
 We cannot see
 We cannot touch
 We can feel them by the neuro-sensorial organs (except radiation)
 We can measure them in the occupational workplace/environment
 We cannot measure them in the human body (except ionizing radiation)

5. Which are the effects?
• Time of exposure
• Level of
exposure
Source
Worker
- occupational diseases
- occupational related
diseases
- accident of work
Workplace
- days of incapacity of
work
- a new worker
- risk insurance

6. Noise
 What is noise?
 a group of unwanted or/and wanted sounds which produce an unpleasant
hearing sensation, sometimes disturbing, which impede communication
 an annoying sound
 The perception depends on the listener and the circumstances (e.g. rock
music can be pleasant for a person, but uncomfortable in a surgery room).

7. What is occupational noise?
 a complex of sounds, of variable intensities and pitches, having different
characteristics, rhythmic or rhythmless, produced continuously or
discontinuously by machines, tools, devices, means of transportation, the
human voice, etc, during the performance of the professional activity

8. What is the Threshold Limit Value?
 The Threshold Limit Value (TLV) depends on the work specificity
(International Standard, ISO 1999-1990).
 The Law establishing this is the Directive 2003/10/EC of the European
Parliament and of the European Council.
 This directive is to be transposed into the national legislation of all Member
States.
 In the European countries the maximum admitted values (Leq - weekly
equivalent acoustic level) at the workplace with normal neural-sensorial
solicitation are between 85 and 90 dB (A).

10. What are the Health Effects?
Auditory
Acute :
 tinnitus
 acoustic trauma
Chronic:
 hypoaccousia
 Noise Induced Hearing
Loss (NIHL)
Non-auditory
 sleep disturbances
 general effects
(cardiovascular, metabolic
changes)
 behavioural effects

11. How can you protect from noise?
Medical measurements
 Pre-employment examination
 Periodical examinations
 Audiometric testing
 Risk assessment
 Risk management

12. What are the health effects of ultrasounds and
infrasound?
Ultrasounds
Acute effects: 18-30 kHz
 headache, fatigue at the end of
the day, sleepiness during day
time, the feeling of pressure
inside the ear, walking
disturbances, numbness, and
sensitivity disturbances.
Chronic effects:
 vascular disturbances, increase of
the central and skin
temperatures, hyperglycemia,
increased number of eosinophiles
Infrasound
Acute exposure:
 to intensities high enough to be
heard, it can determine a
decrease in vigilance
Chronic exposure:
 to normal levels present in the
environment, there is not enough
evidence

13. How do we protect from ultrasounds and
infrasound?
 By respecting the technical prophylactic measurements concerning noise
exposure
 In case of ultrasounds, wearing rubber cotton gloves may be of help

14. Vibration
 Vibrations are the mechanical oscillations of an object
reported to an equilibrium point.
 Vibrations enter the body through the organ in contact
with the vibrating equipment. There are two situations:
 the hand-arm vibration exposure, when a worker operates hand-held
equipment such as a chain saw or jackhammer, the vibrations affect the hands
and the arms;
 the whole body vibration exposure, when a worker sits on a vibrating seat or
stands on a vibrating floor, the vibrations exposure affect almost the entire
body.

15. What are the workplaces with vibrations?
 Mining, constructions, forestry work, car driving (tractor, excavator, and
bulldozer), helicopter, etc.
 Sources of vibrations: pneumatic tools, chain saw and other vibrating
tools.

16. What are the health effects?
Hand-arm vibration
exposure
Whole body vibration
exposure
20-500 HZ < 20 Hz
Target organs:
- blood vessels of the fingers
- sensitive nerves of the hand
- bone-muscle-articulation
- structures of the hand-arm
system
Target organs:
- organs of the abdominal cavity
- circulatory system
- vertebral column
- nervous system

17. Laboratory investigations
Hand-arm vibration
exposure
Whole body vibration
exposure
Cold provocation test
Vascular Doppler test
Infrared thermograph test
Vibration perception test
Other investigations:
- Bone X –ray
- Biological
Bone X ray (lumbar vertebral
column)
RMN
Biological investigations
Gastric examination
Renal examination

18. Treatment
 Cessation to vibrations exposure
 Symptomatic treatment
Medical prevention
 Pre-employment examination
 Periodical medical examination
 Increased caution for people with cardiovascular diseases and musculo-
skeletal disorders

19. Radiation
What do we know about radiation?
 Radiation is a complex process through which the energy emitted by a source
is transmitted through different media and then absorbed by a support.
 According to the ionizing capacity of the matter, we have ionizing and non-
ionizing radiation.

20. Visible Light
Enough energy
to produce
ionization

21. Classification according to the ionizing
capacity of the matter
Ionizing radiation Non-ionizing radiation
Electromagnetic:
- X rays
- Gamma rays
Corpuscular :
- Alpha particles
- Beta particles
- Neutrons
Electromagnetic fields
Infrared (IR)
Ultraviolet (UV)
Visual radiation (V)
Laser
Microwave

22. Characteristics of radiation
Source Energy
deposit
The first interaction
Transport

23. Ionizing radiation
How can we measure radiation?
The radiation dose is the most important measure from the
medical point of view. The radiation dose can be expressed
as:
 Absorbed dose (D) - the amount of energy absorbed per unit
weight of the organ or tissue;
- measured in Gray (Gy).
 Equivalent dose (H) - Absorbed dose in Gy multiplied by a
weighing radiation factor (WR) which expresses the biological
effectiveness of radiation;
- measured in Sievert (Sv).
The equivalent dose takes into consideration the radiation type,
because the equal doses of all types of ionizing radiation are not
equally harmful.
Effective dose (E) E = T wT.HT where wT.= weighing tissue/organ
factor and HT = equivalent dose in tissue/organ

24. Where we can find ionizing
radiation?
Sources of radiation:
 natural (85%): cosmic, the natural radioactivity of the earth,
the natural radioactivity of the air (Radon), the natural
radioactivity of the water, vegetation, and food;
 artificial (15%): medical, occupational, and from other
sources such as: industrial, nuclear research, nuclear
accident (Chernobyl, Fukushima).
Workplaces: the medical sector (X-ray examinations ~
1mSv/year, nuclear medicine ~ 1-2mSv/year), research
(operating accelerators ~ 4-5mSv/year), industry (industrial
X-ray examination, radioisotopes production, manufacturing
of luminescent products), nuclear industry, natural sources
(Radon in the uranium mining activity, the cosmic radiation
during plane flights).

25. What are the Health Effects?
TYPES OF
EFFECTS
CELL DEATH
DETERMINISTIC
Somatic
Clinically attributable in
individual exposure
E.g. acute radiation disease,
burns
Existence of a threshold
(under this, no
observable effects)
Severity increased by
dosage
CELL
TRANSFORMATION
STHOCASTIC
Somatic and hereditary
Epidemiological attributable in
large population
E.g. cancer, mutations
No threshold
Probability of the effect
increases by dosage
BOTH
ANTENATAL
Somatic and hereditary
Expressed in the foetus,
newborn or descendants

26. Radiosensitivity (RS)
High RS Medium RS Low RS
Bone marrow
Spleen
Thymus
Lymphatic
nodules
Gonads
Crystalline
Lymphocytes
Skin
Mezodermic
tissue of
organs (e.g.
liver, heart,
lung etc)
Muscles
Bones
Nervous system

27. Clinical Aspects
ACUTE CHRONIC
GENERAL
 Radiation Acute
Syndrome (RAS)
LOCAL
 Acute radio dermatitis
 Eye impact
 Infertility
GENERAL
 Chronic radiation disease
LOCAL
 Chronic radio dermatitis
 Skin cancer

28. Treatment
In case of over-exposure:
 Identify the affected people, select, isolate and monitor them
 Proper protection of the personnel involved in the rescue and in the
research !!!
 Reconstruct the accident through physical and biological measurements
and clinical data
 Symptomatic treatment (antivomitives, sedative drugs, etc)
In local exposure the prognosis is better.

29. How can we protect from ionizing radiation
?
Technical and organizational measures
 Increase the distance from the source
 Reduce exposure time
 Protect exposed people
Fundamental concepts of radioprotection:
 Justification
 Optimization
 Dosage limitation

30. How can we protect from ionizing
radiation ?
Medical measures
- blood count !!!
- nucleoli test
- ophthalmological examination
- psychological test

31. Non-ionizing radiation
 Non-ionizing radiation: electro-magnetic fields, infrared, ultraviolet
(UV), visual radiation, laser, microwave
 How do we measure non-ionizing radiation?
Measure unit: frequency – Hz (cycle/second), wavelength – λ (m)

32. Non-ionizing radiation
Ultraviolet Visible Infrared
Source Natural: sunlight
Artificial: welding
activities, cutting
with plasma, laser
with UV, incandescent
metals, lamp with Hg
vapours, etc
Natural: sunlight
Artificial:
electric lamp,
lamps with high
intensity,
flashes, laser,
video terminals,
etc
Natural: sunlight
Artificial: any
object with
temperature
higher than 0
degrees absolute
Microwave radiation and radiofrequency wave
Source: in radio communications, industry (heating), drying, hardening of
metal, food sterilization, display screen, in medicine (diathermy)
Very low frequency radiation (<200Hz, especially 50-60 Hz) include
the frequencies used for the high voltage electric lines and the domestic
electric lines
Laser (Light Amplification by Stimulated Emission of
Radiation)
Source: cutting of metals, plastics, in communications, in medicine

33. Non-ionizing radiation
What are the Health Effects?
 Two types:
- thermal effect
- non-thermal effect (genetic, phototoxic, and photo-allergic)
 Main affected organs: - eyes (Laser exposure)
- skin
 Clinical effects of exposure to very low frequency are
very controversial. Research has focused on possible
carcinogenic, reproductive, and neurological effects.
Other suggested health effects include cardiovascular,
brain, behaviour, hormonal and immune system changes.

34. Non-ionizing radiation
Treatment:
 Restriction or cessation to the exposure
 Specific treatment of the eye and skin lesions

35. Non-ionizing radiation
How can we protect from non-ionizing radiation?
 Medical measures
People having mechanical or cardiac implants are not allowed on/ around
electromagnetic fields !!!
 We can not employ people with:
 eye conditions
 central nervous system condition
 cardio-vascular condition
 skin diseases

36. How can we protect from non-ionizing
radiation?
Source
Technical and organizational measures
Worker
III. At the worker level
E.g.:
- individual protection
equipment (proper
clothing, special eye
protection)
- protection cream
II. Reduce exposure time
Increase source
distance
Use protective shields

37. Lighting
 What do you know about lighting?
 Light is a key element for our capacity to see and it is necessary to appreciate
the form, the colour and the perspective of the objects that surround us.
 Light or visible light is electromagnetic radiation that is visible to the human
eye, and is responsible for the sense of sight.

38.  Good lighting implies:
 uniform illumination
 optimal luminance
 no glare
 adequate contrast conditions and use of correct colours as detail and
background
 absence of stroboscopic effect or intermittent light

39. How do we measure lighting?
 The device for measuring lighting is the lux meter.
 The measuring unit for lighting is “lux” (luminance) i.e. the luminous flux per
unit area at any point, on a surface exposed to incident light.
 Legal framework: according to the European legislation
 A good lighting level is necessary to be sufficient (at least equal with the
specific values)

40. What are the sources and workplaces?
 Sources: natural: the sunlight,
artificial: lighting by incandescence, fluorescence, high-
pressure sodium or mercury lamp, low-pressure sodium or tungsten lamp,
mixed lighting (i.e. natural and artificial).
 The sunlight is composed of: 40% visible radiation, 59%
infrared visible radiation, 1% ultraviolet visible
radiation.
 Workplaces: agriculture, constructions, sailing activities, foundries, office
work.
 Professions: workers in outdoor activities in summer and winter, inside
activities with visual solicitation (jeweler, watchmaker, etc).

41. What are the Health Effects?
Poor lighting may affect the workers'
Health
 Visual trouble (visual fatigue,
tearing, and other visual
problems)
 Fatigue
 Headache
 Musculoskeletal disorders
Performance
 Errors
 Accidents

42. Treatment
Workplace Worker
Solving the technical
problems of inadequate
lighting:
- type of light
- position
- distances
- organization of work
- 10 minutes breaks every 1
hour (e.g. fine, very fine,
computer work)
Against visual disorders:
- ophthalmologic eyewash,
vitamins, protection or
correction glasses
Against fatigue:
- vitamins
- antioxidants
Against MSD:
- physiotherapy
- swimming
- NSAID
It is recommended to use natural lighting!

43. How can we prevent the effects of poor
lighting?
Technical measures
 For good lighting it is necessary to have an ergonomic organization of the
workplace and to take into consideration:
 the precision required for the performed tasks
 the amount of work
 the mobility of the worker
 the characteristics of the workplace (windows, type of lighting and the season)

44. How can we prevent the effects of poor
lighting?
Medical measures
 Monitoring the visual capacity of employees before employment and after
that, through periodical examination (usually, a screening examination per
year).

45. Microclimate (cold and warm climate)
 The microclimate is characterized by:
- temperature (dry)
- relative humidity
- air current speed
- surface temperature
- caloric radiation
 Very cold and very hot temperatures could be dangerous to health.

46. Temperature action and worker reaction
• Temperature
• Air movement
• Humidity
Cold/warm
environment Worker
• Proper insulation (protective
clothing)
• Physical activity
• Controlled exposure to cold or
warm

47. How do we measure temperature?
 Measuring device: globe thermometer
 Measuring unit: temperature in degrees Celsius or Fahrenheit
 Legal framework: according to the European legislation

48. Cold exposure
 What are the workers exposed to cold?
Outside: road builders, construction workers, police officers, fire fighters,
emergency response workers, military personnel, transport workers, bus
and truck drivers, fishermen, hunters and trappers, etc
Inside: workers in refrigerated warehouses, meat packaging and meat
storage workers, etc.

49. What are the Health Effects to cold
exposure?
Heat
Loss
• Local effects: FROSTBITE
• General effects: HYPOTHERMIA
Heat
production
+
Heat retention

50. Treatment
FROSTBITE
HYPOTHERMIA
EMERGENCIE
S
FIRST AID
FIRST AID
INCREASE THE BODY TEMPERATURE GRADUALLY !!!

51. How can we prevent frostbite and
hypothermia?
Cold
environment Worker
• Proper insulation (protective
clothing)
• Proper resting periods in a
warm area
• Balanced meals and adequate
warm tea intake
• NO alcohol !!!
Insulated
Cabine
Technical measures

52. How can we prevent frostbite and
hypothermia?
Medical measures:
 pre-employment
 periodical medical examinations
 People presenting the following conditions are not allowed to work in
cold environments:
 cardiovascular diseases
 Reynaud’s syndrome
 otitis, sinusitis
 nephropathy

53. Heat environment
 What are the workplaces with warm/hot exposure?
Outdoor occupations, such as: constructions, road repairing, open-pit mining
and agriculture - summer sunshine being the main source of heat.
Inside occupations, such as: foundries, steel mills, bakeries, smelters, glass
factories, and furnaces - extremely hot or molten material being the main
source of heat; in laundries, restaurant kitchens, and canneries, high humidity
adds to the heat burden.

54. Heat environment
 What is acclimatization?
 The temporary adaptation of the body to work in heat conditions and to which
a person is exposed over time.
 Complete heat acclimatization generally takes 6 to 7 days, but some individuals
may need longer.
 When a person gets acclimatized, the central temperature decreases with up
to 1 degree Celsius and the cardiac frequency decreases with 10-14
beats/minute, compared to a non-acclimatized person in the same conditions.
 This is a consequence of the increased sweating process and a good vaso-motor
control.

55. How does warmth act? What are the
Health Effects?
Body heat
(generated by
working)
Clothing
requirements
Warm
environment
Heat stress
Heat oedema
Heat rashes
Heat cramps
Heat exhaustion
Heat syncope
Heat stroke and hyperpyrexia

56. Treatment
 Removal from the heated environment
 Resting in a cool area
 ± consumption of cool salted drinks
 Heat stroke and hyperpyrexia require immediate first aid and medical
survey !!!

57. How can we protect from heat
exposure?
Source
I. Reduces the radiant
from hot surfaces
Insulation of hot
surfaces
Technical and organizational measures
Worker
III. Protection clothing
Eyes protection
II. Reduce exposure
time
Increase the
distance
Shielding
Ventilation
Reducing the humidity

58. How can we protect from heat exposure?
Medical measures:
 Acclimatization !!!
 a decrease in heat tolerance occurs even after a long weekend. This is the
reason for which it is often not advisable for anyone to work under very
hot conditions on the first day of the week.
 Also, the new employees should acclimatize before assuming a full
workload.
 People with cardiovascular diseases are not allowed to work in heat
conditions.

59. Air pressure
 The activities performed in conditions of abnormal pressure are grouped into
two categories:
 activities performed in hyperbarism (atmosphere compression or
decompression)
 activities performed in hypobarism (pressure below that of the ground level
atmospheric pressure)

60. Air pressure
Hyperbarism Hypobarism
- underwater activities
- scuba divers (the pressure
exceeds with at least 0.1
atmospheres the normal
value)
- pilots
- lift workers
- workers in store-rooms
with
modern fire protection
systems where the
oxygen
content of the air is
reduced
to 13 %
What are the Workplaces and
Workers ?

61. Air pressure
• the trauma of the ears and the sinuses during
compression period
• the toxic effect of nitrogen and CO2 while
working in increased pressure
• caisson disease during decompression period
HYPERBARISM
What are the Health Effects and Treatment?
Treatment : acute forms are medical emergencies and require
Oxygen administration and modifying the pressure

62. Air pressure
• the decompression disease at high altitude
(pilots, aircraft personnel)
• the altitude hypoxia (pilots, aircraft
personnel)
• the lift workers disease
• the high altitude disease
Hypobarism
What are the Health Effects and Treatment?
The effects that occur depend on: how quick the transfer from
normal pressure to decreased pressure is, how trained the
person is and whether he adapts to the pressure.
Treatment: returning to the level of the ground;
specific treatment according to the condition of the
patient.

63. How can we prevent the effects of exposure
to hyperbarism and hypobarism?
Hyperbarism Hypobarism
Technical measures:
- by assuring good quality and
good
temperature of compressed air
- by respecting the decompression
protocol
- by reducing the work time ~
deep
- availability of a special room for
relaxing and clothing
Technical measures:
- by pressurizing the planes
- by climbing in stages
Medical measures:
- pre-employment examination
- periodical examinations
- adaptive control
Medical measures:
- pre-employment examination
- periodical examinations
- adaptive control

64. THANK YOU!!