Visibility and not illumination Reduces mishaps

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 glareUnder illumination could result in erroneous judgementProper visibility is necessary to fully identify the hazard and to judge

SizeShapeDistance If the object is moving the rate and direction And host of other factors

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, BEAMWe 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

• 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

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

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

• 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

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

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

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?

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 putHumans 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 toleranceIllumination should therefore address maintenance , ore dressing and all supplementary facilities. Also areas where entry is prohibited should have visible warning systems

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)

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/winterTherefore this cannot be a uniform format but need basedlay out. Even this would change as technology and efficiencylevel of fixtures change

In the case of mines flat bedded deposits on plain topography, light fixtures can be all around thus ensuring uniform illumination

Night view, Mine has tower light all around .Observe illumination levels on blasted muck , bench below and away

Mining on hill top and slope

If lighting towers are high above they tend to leave shadow zones close to bench toe, unless supported by light from the other direction

Effect of Tower height

Egs our Tower lights in wagon loading yardsLot of shadow area beneath tower

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

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 pointsFixture 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

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 etcLuxmeter 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 etcLuxmeter should be calibrated

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.

Age Effects on VisionYellowing of Lens

(age in years)

Degradation of lens decreases effective light level and effective

contrast (due to scatter)

Average miner 43 yrs old40% less light than 20 yrs old

Night vision decreases with ageSmaller pupilEye less able to adapt to light Cloudy eye lens

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

Hauling

HEIGHT OF LUMINAIREThe 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 GLAREThe 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.

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.

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.

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

Haul roads

One in every three poles may be at just above tyre height. This would avoid glare while crossing of dumperIn case of medians growing of bushes avoids glare as also contain dustEven if Illumination is of best standard a dusty condition will reduce visibility levels

Fixtures on Haul roadsLocation 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.

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.

It is also a safe practice to hang self reflecting type domes along the guard wire to caution the drivers

Video

Travelled with raised body also Obstruction not visible

In our anxiety to meet the standards, it is overplayed resulting in glare that leads to temporary blindingthe upcoming dumper in gradient will throw light beams direct to the down going oneMedians where available should be formed to avoid glare from opposite direction, may be with bougainvillea plantationsLight 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 outageElectricians should be trained in handling and disposal of fixtures containing toxic material like mercuryThe dumper check list should also include a night check as well as beam alignment

Ramp and glare put barricades in medians

Turnings and glare put barricades in medians

Hit culvert and toppled

Culverts:-provide auto blinkers as indicatorsCulverts 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

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 facilityStep 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.

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

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 cableLighting 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

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

Dumper toppled while reversing in water logged areaCrack in the side was not visible due to poor illumination

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

VisibilityDrivers 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

Efficiency of camera would reduce with poor illumination, Slush due to excess wetness or dust

Camera in the rearScreen in cabin above operator

Automatic cleaning of rear vision systemsAutomatic cleaning of rear vision systems

Illumination and isolation of area like unloading hopper area , Illumination and isolation of area like unloading hopper area ,

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

Variation in illumination as the operator gets in or out should be considered.

poor cab illumination and/or glare from reflective sources

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

restricted work space needs local illumination

Highly reflective striping and numbers to clearly delineate the truck dimensions and number at night

• 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

Ht should reach dumper driver cab Light connected to ignition switch

Result of parking in front of big haul truck

Mine foreman wanted to drive the truck while the driver ate lunch. The truck driverpulled the haul truck onto the spoil dump area, exited the truck, and walked to theright side of the truck to wait for the foreman. The foreman arrived in a 1/2-tonpickup truck and parked it adjacent to the right side of the haul truck, facing into thepath of the haul truck. The foreman left the engine running and watched as the truckdriver entered the pickup truck. The foreman entered the haul truck and sounded atwo-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.

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

Hand lamps for illumination

General Requirements of Artificial LightingThe 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.

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.

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HEMM Maintenance Shed

(+)40 lumps

(+)10- (40) Calibrated ore

Classifier fines

Cyclone fines

Primary crusher

Secondary crusher

Scalper

Screen

classifier

Cyclone

Thickener

Crusher Floor

Illumination in confined spacesConveyor belts Below tail pulley

Nip Points

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• 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

Emergency lighting where men are near machinery to take care of sudden outage &

leading to accidents

Put illuminated barricades for areas under construction, pits, etc

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 topplingConnections 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.

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

Parking Area

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 glareAlso there should be red and Green light installed with audio to enable dumper operator to reverse

Night view

2 No’s of Xenon lights of 1000 W for each excavator

Such high powered illumination can be a hazard if dumper operator also is on the same side

Solar blinkers provided all along the safety bunds for clear identification of Haul Roads

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.

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Thank you