2. Illumination involves a source of light being emitted.
To have visibility, the human eye requires illumination of light for
things to be seen . Visibility is the state of being seen. To be visible
you must have a level of illumination--a source of light.
Excess of illumination can result in glare
Under illumination could result in erroneous judgement
Proper visibility is necessary to fully identify the hazard and to judge
Size
Shape
Distance
If the object is moving the rate and direction
And host of other factors
3. The saying is once bitten twice shy
We are in a similar situation so let us think before
acting & not flout the norms
BOOM, BANG, BEAM
We had a boom with china market &flouted norms
Got a bang by a blanket ban that lead to
suspension of activities
Now we should beam with ideas to work
Our Sustainability lies on compliance and not
flouting the statutory norms
4. • Working within forest area after day light
hours may by itself become an issue
• In the post ban era as mines restart , legal
implementations are expected to become
more stringent
• If we have legal sanction to work we need
sufficient visibility for safe working
• Sufficient does not mean too many but
judicious use of resources
5. It doesn’t matter how many resources we have
If we don’t know how to use them, they will never be enough
We may have too many lighting fixtures but if they are not
properly positioned we will still have an issue
6. HIGH BEAM LIGHTS result in glare
This will happen in over illumination .
Improper utilization of resources
The time taken by the eyes to adjust in changed illumination levels depends
upon age etc.
Glare could result in fatality Driver/ on coming truck/pedestrian could be any or
all
7. • MMR 146,148
• Circular 3 of 1976
• 13 of 1979
• Circular 4 of 2009 Explains about uniformity ratio
,Glare, Lumnaires , Lumens & Lux
• Maintaining Lighting Plan
Legal status of Mine Illumination
Illumination is an activity and should be subjected to
RISK ASSESSMENT
8. CENTRAL ELECTRICITY AUTHORITY REGULATIONS, 2010
97. Lighting, overhead lines, communication
and fire precautions.-
(1)In a mine illuminated by electricity, one or more flame safety lamps, or
other lights approved by the inspector of mines, shall be maintained in a
state of continuous illumination in all places where failure of the electric
light at any time shall be prejudicial to safety.
(4) In case of mines, minimum clearance above ground of the lowest
conductor of over head lines or over head cables where dumpers or
trackless vehicles are being operated shall not be less than twelve meters
in height from the ground across the road where dumpers or trackless
vehicles cross
9. Purpose of Illumination
#The OperaTOr wiTh The abiliTy TO see, especially
aT nighT and/Or be aware Of The peOple , vehicles,
sTrucTures Or OTher ObjecTs TO ensure The safe and
effecTive OperaTiOn Of The equipmenT TO avOid
cOllisiOns
#prOvide The abiliTy fOr The OperaTOr TO
apprOpriaTely warn persOns in The viciniTy Of
equipmenT OperaTiOn
#OpTimise visibiliTy Of equipmenT TO OThers
OperaTing in The viciniTy
10. To avoid accidents due poor illumination
– Collisions
– Slip/trip/falls (ore dressing areas, drills , getting in and out of
Machines, pump locations, confined spaces, nip points
– Falls of ground (drilling, loading, dumper placement close
face/edge)
– Above all creating a safe environment
• GLARE IS PARTICULARLY AN ISSUE IN SAFETY. BRIGHT AND/OR
BADLY SHIELDED LIGHTS AROUND ROADS UN EXPECTEDLY,
MAY PARTIALLY BLIND DRIVERS OR PEDESTRIANS AND
CONTRIBUTE TO ACCIDENTS
Why look at mine lighting?
11. A cat cannot see properly in
ordinary day light
Animals like tiger are hunted
by focusing search light that
blinds them by glare.
They get confused and
remain stay put
Humans get partially blind by
glare(egs) in marriage halls
when light is focused
Illumination does not mean
merely fixing lights all around but
placing lights judiciously to
ensure that all areas where men
or machine have access
öare clearly visible
öwithout glare or shadow,
öuniform all through within
tolerance
Illumination should therefore address
maintenance , ore dressing and all
supplementary facilities. Also areas
where entry is prohibited should
have visible warning systems
12. Even in the same location
Factors influencing illumination
• Type &size of fixtures
• Spacing& Height
• Condition of haul road
• Shadow and bright zones
• Age and vision of individuals
Season Summer Frequent dust whirl wind, Winter(Fog), Rains
(Glare)
13. Illumination does not have a fit forget or universal solution .
It depends upon
۩ location of deposit like slope of hill,
۩ Production- no of benches, excavators
۩ Flat topography shallow( Dip within say 8 deg)
۩ Flat topography deep ( steeply dipping)
۩ Light absorbing characteristics of ore/waste(Mn Clay, phyllites)
۩ season rainy/summer/winter
Therefore this cannot be a uniform format but need based
lay out. Even this would change as technology and efficiency
level of fixtures change
14. In the case of
mines flat
bedded
deposits on
plain
topography,
light fixtures
can be all
around thus
ensuring
uniform
illumination
15.
16. Night view, Mine has tower light all around .Observe illumination levels on blasted
muck , bench below and away
19. If lighting towers are high above they tend to leave shadow zones close to bench
toe, unless supported by light from the other direction
20.
21. Effect of Tower height
Egs our Tower lights
in wagon loading
yards
Lot of shadow area
beneath tower
22. Ref Prof N C Karmakar, Prof Y V Rao, M Aruna, Lighting Haul Roads in Surface Coal Mines –
A Design Based on Reflectance IMEJ ; Feb 2008
Beyond certain height we loose the efficiency 8 -10 m is ideal
23.
24.
25. From pole take readings at regular intervals and draw contours with one fixture and
then with both fixtures
This will guide in locating the fixtures with respect to loading points
Fixture could be of low height say 6-8 m and portable. Generally 2x400watts Metal
Haloids on each structure can take a face length 400m and maintain glare free
illumination of 10 lux
26. Take readings at regular intervals in
all benches with no other source of
lighting , preferably on a new moon
day
This would vary in wet and dry
ground conditions, dust, fog etc
Luxmeter should be calibrated
Take readings at regular intervals in
all benches with no other source of
lighting , preferably on a new moon
day
This would vary in wet and dry
ground conditions, dust, fog etc
Luxmeter should be calibrated
27. Uniformity of light distribution (Uniformity Ratio)
Good lighting is not only a matter of more light but
is also a matter of its proper distribution. For
example, a well-lit road surface is expected to
appear evenly illuminated, with no apparent dark
patches and glare. It is possible only when the
distribution of light is more or less uniform
across the length and breadth of haul road.
Uniformity ratio of illuminance on a given plane
is a measure of the variation of illuminance over
it.
28. Age Effects on Vision
Yellowing of Lens
(age in years)
Degradation of lens decreases
effective light level and effective
contrast (due to scatter)
Average miner 43 yrs old
40% less light than 20 yrs old
Night vision decreases with age
Smaller pupil
Eye less able to adapt to light
Cloudy eye lens
29. Loading points
• Even though illumination from
excavator ,dumper reporting for load/ moving
out after load would be there , they are
neither constant nor consistent. Rather they
could lead to distraction , glare etc
• Loading as far as possible should be only
with external source of light.
• Dumpers that report should be either with
parking light or low beam only
33. HEIGHT OF LUMINAIRE
The height of Luminaire shall be the vertical
distance from the ground directly below the
centerline of the Luminaire to the lowest direct-
light-emitting part of the Luminaire
GLARE
The sensation produced by a bright source within
the visual field that is sufficiently brighter than the
level to which the eyes are adapted to cause
annoyance, discomfort, or loss in visual
performance and visibility.
34. Glare is particularly an issue in road safety, as
bright and/or badly shielded lights around roads
may partially blind drivers or pedestrians
unexpectedly, and contribute to accidents.
Caused by high contrast between light and dark
areas, glare can also make it difficult for the human
eye to adjust to the differences in brightness.
Light shining into the eyes of pedestrians and
drivers can obscure night vision.
35. Glare can be categorized into different types.
Blinding glare describes effects such as that caused
by staring into the Sun. It is completely blinding and
leaves temporary or-permanent vision deficiencies.
Disability glare describes effects such as being
blinded by oncoming car lights, or light scattering in
fog or in the eye, reducing contrast, as well as
reflections from print and other dark areas that render
them bright, with significant reduction in sight
capabilities.
36. Discomfort glare does not typically cause a dangerous situation in
itself, though it is annoying and irritating at best. It can potentially cause
fatigue if experienced over extended periods.
Glare can also result in reduced contrast, due to light scattering in the
eye by excessive brightness, or to reflection of light from dark areas in
the field of vision, with luminance similar to the background luminance.
This kind of glare is a -particular instance of disability glare, called
veiling glare.
Glare is particularly an issue in road safety. as bright
and/or badly shielded lights around roads may
partially blind drivers or pedestrians unexpectedly,
and contribute to accidents
37. Haul roads
One in every three poles may be at just above tyre height.
This would avoid glare while crossing of dumper
In case of medians growing of bushes avoids glare as
also contain dust
Even if Illumination is of best standard a dusty condition
will reduce visibility levels
38. Fixtures on Haul roads
Location of Poles :–away from haul road to avoid damage due to
trucks running out of control. Size of pole should be strong enough to
take the load but not too heavy making it cumbersome to handle.
39. Over Head line conveyor crossing etc:- Except
under unavoidable conditions overhead line should not
cross the road especially in areas close to unloading
points. If it be necessary the height of the lowest
conductor/guard cradle should be more than the
height of raised body of dumpers using such roads.
Also sufficiently strong barrier to be made to avoid
damage to pole.
40. It is also a safe practice to hang self reflecting type domes
along the guard wire to caution the drivers
43. In our anxiety to meet the standards, it is overplayed resulting in
glare that leads to temporary blinding
the upcoming dumper in gradient will throw light beams direct
to the down going one
Medians where available should be formed to avoid glare from
opposite direction, may be with bougainvillea plantations
Light poles should be beyond the embankment and all poles
should have reflectors at operator level. As a precaution where
persons are likely to cross haul roads solar based fixtures
should be available to take care of power outage
Electricians should be trained in handling and disposal of
fixtures containing toxic material like mercury
The dumper check list should also include a night check as well
as beam alignment
47. Culverts:-provide auto blinkers as indicators
Culverts crossing the road should be straight on the
culvert and approaches to a distance 20 meters or braking distance
of maximum permitted speed in that section whichever is more to
avoid hitting against culvert parapet wall. Culverts should be
painted with zebra lines to assist visibility. It is also a good practise
to make old tyres stand in front of parapet wall
48. Routing of cables :– should cross roads at designated locations
and should be marked with caution board to avoid digging. Junction
boxes should be above ground level &provided at regular intervals.
Cables should be buried sufficiently deep to avoid crush injury due
to load. Cable routes should avoid areas likely to get inundated,
liable to slide etc., .
Isolation switches and lock out :- Haul road lighting conductors
run to sufficiently long distances. Isolation switches and boxes
should be provided at regular intervals with lock out facility
Step ladders welded on pole:- As the face advances ,it would
become necessary for adjusting ,focusing & at times to clean the
cover of the fixture. This should be easier and it would be safer to
weld slip proof rungs at equal spacing throughout. Also there
should be provision to adjust the height of the fixture.
49. Visibility of Poles:-Pole should be painted with zebra (black/yellow)
or white to ensure visibility and have vertical luminescent paint
marker on both sides
Earthing:- The entire lighting system should have independent
efficient earthing.
Access to pole should be safe:-. Poles not to be located at bench
edge. Lowering of luminaire and hoisting back to be with proper
arrangement. For this purpose hooks should be provided beneath
rungs
50. Dump lighting– Needs Visibility of edge to identify cracks if any
and facilitate dump inspection, reversing and unloading
Cable routing to be considered should ensure that it does not run
on haul road as the area will be soft and could damage the cable
Lighting source should located in area that it does not create
shadow or glare
The rays of light should at no pint of travel directly fall on the
driver .
Illumination should be available for both sides of dump Source of
light should be dedicated, focused and is in good condition
51. Blasting:- Depending upon the proximity to blasting and fly rocks
the fixture would need to be protected with grills.
Height of fixture and tilt angle play crucial role. This can be
achieved by proper maintenance of fasteners and other fittings
connected to it in good condition . Rusted fasteners makes the
job difficult Electrical connections should be through proper
junction box, connecters etc. Mere twisting and applying
insulation tape is not a permanent solution
52. Dumper toppled while reversing in water logged area
Crack in the side was not visible due to poor illumination
53. A warning light system has the capability of warning truck drivers when they near the
edge of dump and can provide an effective safeguard in addition to well maintained
berms. The warning light system consists of a laser and flashing light. The light flashes
once every two seconds to indicate that it is operational. When the truck interrupts the
laser beam, the light glows brightly without flashing, providing an indication to the truck
driver that the stopping point has been reached. This light has been successfully tested
54. Visibility
Drivers get some help for improved visibility with
gadgets like Camera, Rear view mirror, Proximity
sensors etc.
Audio visual alarms warn their intentions to reverse.
Without these gadgets his condition can be similar to
one sitting in a two storied house with only windows in
the sides and front .
Rains, fog, dust, dark hours, bad maintenance etc.,
reduce these gadgets efficiency
55. Efficiency of camera would reduce with poor
illumination, Slush due to excess wetness or dust
Camera in the rear
Screen in cabin
above operator
57. Illumination and isolation of area like unloading hopper area ,Illumination and isolation of area like unloading hopper area ,
58. Catwalks, handrails, and other external
objects located or designed so operator
vision is impeded. (Including line of site to
mirrors)
Well designed cabs with open
uncluttered view
Even if illumination levels are in order glare that could occur
due to the height at which the operator is stationed should be
considered
59. Variation in illumination as the operator
gets in or out should be considered.
poor cab illumination and/or glare
from reflective sources
60. Inadequate lighting for headlights, tail,
reversing, turn,brake, flashing light, and
receptacles for light fittingsthat suit
standard & alternative lights
Ineffective windscreen wipers and
washers with reservoirs of
insufficient capacity
63. • Clear directive exists by way of circular for independent
road for service vehicles exists.
• They also need to move on haul roads to attend to
dumpers in distress, repairs to loading equpt etc
• Also they need to park close to these equpts.
• On many occasions they are not noticeable while
approaching close or after repairs. Dumper / loader
starts and these smaller ones get run over. There has to
standard procedures. Also a red indicator and flag has to
mounted on top of thee small ones and visible at the
dumper operator level
64. Ht should reach dumper
driver cab
Light connected to
ignition switch
66. Mine foreman wanted to drive the truck while the driver ate lunch. The truck driver
pulled the haul truck onto the spoil dump area, exited the truck, and walked to the
right side of the truck to wait for the foreman. The foreman arrived in a 1/2-ton
pickup truck and parked it adjacent to the right side of the haul truck, facing into the
path of the haul truck. The foreman left the engine running and watched as the truck
driver entered the pickup truck. The foreman entered the haul truck and sounded a
two-horn signal. Both the pickup truck and the haul truck moved forward
simultaneously. The haul truck ran over the cab and hood of the pickup truck causing
fatal injuries
Never park in the blind
spot of mobile
equipment.
Always ensure that
persons and other
equipment are in the
clear before moving
equipment.
67. 12/24 V High intensity light
with magnetic base
For use in maintenance and where needs to
be placed /handled etc magnetic base low
voltage lights should be used.
Supply could be tapped with the help of Step
down transformers and metal clad Ceraamic
pin and socket
Portable gen sets should have specific SOP like earthing,
mast folding, shifting instructions , protection from
lightning etc
69. General Requirements of Artificial Lighting
The requirements for good illumination in mines, and other
work places may be summarized as follows:
1) Sufficient illumination should be provided for each
workman irrespective of his position on the working space.
2) The lamps should be properly selected and so installed as
to avoid or minimize strain on the eyes of the workmen.
The type and size of lamp should be adapted to the
particular location and height and class of work in question.
3) The lamps should be operated from sources of supply
which will ensure continuity of service and steadiness of
light.
70. 4) Adequate illumination should be provided from overhead lamps
so that sharp shadows may be prevented as much as possible,
and in such manner that individual lamps close to the work may
be unnecessary except in special cases.
5) In addition to the illumination provided by overhead lamps,
individual lamps should be placed close to the work if they are
absolutely necessary, and in such cases the lamps should be
provided with suitable opaque reflectors. The type of lamp should
be decided based on the nature of work, work environment and
the extent of ambient illumination.
6) To meet sudden outage and accident minimum illumination at
vantage points should be available. This could be solar or
inverter based.
77. • Ore dressing is done in confined atmosphere that leads to
creation of dust. While coarser ones may settle down faster, finer
remains air borne , gets coated on the fixtures and reduces the
visibility this Conveyor belt walkways are one such location
• Life of fixture gets affected due to vibration
• Sudden failure of lighting circuit while crusher may continue SOP
should address this issue and operators given appropriate
training
• hopper where loaded trucks should get proper illumination from
both sides also there should be clear indicator for waiting
dumper to reverse
78. Emergency lighting where men are near
machinery to take care of sudden outage &
leading to accidents
80. Illumination Emergency prepared ness
Portable generator set single or three phase 10kva air colled with switch board
independent of generator. (Provision for earthing of generator set as it will be
on tyre mounted trailer- may be about 4 mtrs conductor bolted on to base and
other end a M.S pipe one end chamfered to drive down.
Metal haloids or any glare free lighting fixtures with range of 1.5 times the
length of dump slope. The illumination at farthest point should be enough to
read a wrist watch. These fixtures should be mounted on stands with a max
height of 2.5 meters and provision for adding counter weight at the base to
prevent toppling
Connections should be with metal clad pin and socket system.
Step down transformer 220 input—12 V out put one(to avoid electrocution).
Sufficient length cable to with stand 12 V to take 12 V hand held flame proof
inspection close to dumper in distress. Cables to be in drum with pin and
socket for extension.
Fuel sufficient to meet 10 hrs of continuous. Spare bulbs for above two sets.
81. Flame proof fixtures with cut off facility from entrance
fuelling areas,
gas cylinder storage,
Lubricants
stores
Hot seat change locations facilitate—
• walk around check
• steps visibility
Washing ramps
83. Crusher Hopper Area
Focusing of light should ensure that the light does not fall on the rear view
mirror of dumper , reflect and result in glare
Also there should be red and Green light installed with audio to enable dumper
operator to reverse
87. ENERGY SAVER GLOBE –MERCURY
EXPOSURE
What happened.
The energy saver globe fused.
He did not wait for the globe to cool down,
Standing on a chair with a piece of cloth and
removed the energy saver globe.
Due to the heat of the energy saver globe fell
down and exploded .
He stepped into the broken glass and exposed
mercury powder.
Admitted to hospital for treatment of the cuts.
Spent two weeks in ICU and at one stage it was
feared that his foot need to be amputated.
Currently his foot is connected to a vacuum
pump to remove continuously dead tissue.
Long road of recovery is awaiting him.
87
