MINE ENARGIA Concetto 2k13

Mining Hazards and Safety

B. Lokeshnath Yadav (2nd

year)

B.Tech in Mining Engineer

with DD with M.Tech

ISM, DHANBAD

IS MINE A SAFE PLACE TO WORK?

Of course Mining is hazardous profession….

Hence our endeavor to bring down the

hazards by all available means to an

acceptable level must continue

Why…??

• The job involves the extraction of precious

stones and minerals deep within the earth.

• In addition, miners use heavy machinery and

other specialized equipment and tools that

can be risky to operate.

• Mining is considered as toughest job next to

Army in USA.!!

Indian Scenario…

• The Mining Industry in India is a major economic

activity which contributes to the major economy

of India.

• Since Mining in India is not fully mechanized,

mine hazards prevail more commonly.

• Hence Indian Government established an

organized body called DGMS in Dhanbad,

Jharkhand

Role of DGMS...

• Inspection of Mines

• Investigation into-

- accidents

- dangerous occurrence

- emergency response

• Approval of mine safety equipment, material & appliances

• Certification of Explosives to be used in mines.

• Promotes Safety Education and Awareness Programmes.

Trends in Fatal accidents and Death rates in Coal mines:

1951

1961

1971

1981

1991

2001

2005

2009

2010

2011

0

50

100

150

200

250

300

350

No.of fatal accidentsNo. of persons killed

Source: Annual Report 2011 of DGMS

HAZARDS OF MINING

Some Hazards that Miners face:

• Cave-ins, Ground and Rock Fall.

• Side fall and collapse of Pillars.

• Gas Explosions.

• Chemical Leaks.

• Electrocution.

• Fires.

• Ground Movements.

• Haulages and Machinery

• Miscellaneous.

Cave-ins, ground and Roof falls:

• A cave-in occurs when a geologic formation, mine or

structure collapses, usually during mining or

tunneling.

• This underground mining accident occurs when proper

safety measures have not been done on the walls and

ceiling of the mineshaft.

• Generally roof supporting is done by various

techniques like roof bolting, timber and steel supports.

Safety Measures against Cave-ins and Roof Falls:

• Geo mechanical properties of overlying rocks are studied

and scientifically designed support systems on the basis of

ROCK-MASS-RATING (RMR) are applied.

• Strata control cells have been established in all coal

subsidiaries.

• Introduction of Mechanized Drilling by roof bolting

machines.

• Emphasis on development of indicators for detecting

impending load on roof.

One man operated compact mechanized cable bolter that delivers long term reinforcement to underground mines and a means for production and dilution control to mass mining methods

20072008

20092010

2011

0

2

4

6

8

10

12

14

16

18

Distribution of Fatal Roof Fall Accidents by Company:

CIL SCCL TISCOSource: Annual Report 2011 of DGMS

Hazards caused by Side Fall:• Failure to make and keep the sides secure by providing

benches of safe height and adequate width or by sloping

• Creating dangerous overhang by undercutting

• Not taking adequate safety measures in geologically

disturbed ground

• Collapse of partings or pillars during extraction of

developed coal seams

• Inadequate inspection of the sides

Safety Measures against Side Fall:• Side of working should be kept secure.

• Support should be set as per systematic support

rules.

• Fencing should be provided in unauthorized

area.

• Stress on face mechanization to reduce

exposure of workmen in active working zone.

Major Side Fall Accidents in India:•Shivrajpur Manganese Mine, Gujrat on

06.12.1910. No. of Persons Killed – 12.

•Bhatti Bajri Mines, on 10th January 1983.

•Bajri / Badarpur Sand Mine on 16th , 24th

January 1983.

Gas Explosions:

• Gas Explosion is a common accident in coal mines

caused by the build up of methane gas (CH4).

• Methane gas and Dust Explosions can also be

triggered by frictional heat and sparks produced

by mining equipment.

• The presence of inflammable gases in

underground mine causes fatal damage.

Measures to be taken against Gas Explosions:

• To prevent pockets of gas from forming, the work

area must be properly Ventilated at all times.

• Make sure the equipment used in coal mines does

not have defects that can create sparks and set off

explosion.

• Maintain reasonable working conditions with

respect to temperature, humidity and amount of

airborne dust.

Fire Accidents:Fires in Mining happen due to different factors

like –

• Gas Leaks

• Electrical defects

• Flammable chemical spills.

• Blasting

• Lighting of fire near exposure of Coal

Safety Measures to be taken against Fire Accidents:

• No petrol power equipment must be permitted.

• Hard held extinguishers should be provided in

various places in mines.

• All underground equipment containing more than

100 liters of flammable hydraulic fluid must be fitted

with an automatic suppression system with suitable

manual activation.

• Storage of flammable substances must be minimized.

Modern Fire extinguishing Systems:• Fire sprinkler system.

• Water spray Deluge system.

• Water mist system

• Foam system.

• Vehicle Fire suppression.

• Breathing apparatus.

• Gas detection system.

Major Fire accidents in History:

Lady Rangi Mica Mine 19 killed on

12.04.1932

Loyabad Colliery 35 killed on

30.01.1936

Jagannath OCP 10 killed on

24.06.1981

New Kenda 55 killed on

25.01.1994

Danger of Inundations:

•Sources of surface water like-

▫Rivers and Nallahs.

▫Tanks and Reservoirs.

▫Accumulated water in old open cast

workings or in low lying areas.

Contd.

• Water from these sources can enter into

Underground Mines through-

1. Shafts and Inclines.

2. Bore holes and geological disturbances like

faults.

3. Broken grounds over caved groves

4. Openings and breaches created by collapse

of overlying strata.

Measures to be taken against Inundations:

• No working should be done vertically below any

river, lake or other reservoir.

• Shaft sites should be located away from faults and

other geological disturbances.

• In case of presence of highly water bearing strata

in the vicinity of the proposed working mining

should be so planned as not to disturb the water

bearing strata.

2007 2008 2009 2010 20110

5

10

15

20

25

TREND IN FATAL ACCIDENTS DUE TO DIFFERENT CAUSES IN NON-COAL MINES

Roof fall Transportation machineryExplosive Electricity

Souce: Annual report DGMS 2011

Environmental Hazards of Mining:

Unregulated mining has the potential to release harmful substances into the soil, air and water

Air-Borne Hazard

• Several types of particulates.

• Naturally occurring Gases.

• Engine exhaust.

• Some chemical vapours.

Physical Hazard

• Noise.

• Segmental vibration

• Heat and changes in Barometric pressure

• Ionizing radiation.

• Acid Mine Drainage

(AMD)

• Heavy Metal

Contamination

• Processing chemical

pollution

• Erosion and

Sedimentation

Specific Contaminants:

Radio Nuclides

Dust & Metal

Health Hazards :

• Physical accidents: Traumatic injury remains a significant problem

and ranges from the trivial to the fatal .

• Chemical Hazards: Crystalline Silica is a serious hazard in mining,

which leads to Silico-Tuberculosis, Chronic Obstructive Pulmonary

Disease, Lung Cancer, Skin splashes with cyanide solutions are

hazardous

• Biological Hazards: The risk of tropical diseases such as malaria and

dengue fever is substantial at some remote mining locations.

Leptospirosis and Ankyloatomiasis.

• Other Psychosocial hazards, Ergonomic hazards.

Need of an Effective Mine Closure Plan:

Other Hazards:

• Explosives - Poorly designed shots can result

in misfires, early ignition and flying rocks.

• Transporting - Vehicle movements

particularly while reversing and Brake failure.

• Face Stability - Rock fall or slide due to geo-

mechanical properties of rock present at

active working face.

Contd.

•Electrical Hazards - Electric shock and/or burn,

Ignition of firedamp or coal dust, Fire arising

from electric defects.

•Rope Haulage - Runaway of tubs due to

breakage of rope, failure of attachment to rope,

failure of couplings and drawbars, Rope should

be selected properly and maintained with care.

Other Safety Measures-

• Permanent lighting should be provided in places

where equipment can be hazardous.

• Cables should be provided with double wire armoring.

• Inspect earthing point regularly.

• Storage of flammable substances must be minimized.

• Haulage curves should be properly designed and

constructed and Bad patches in the track should be

corrected.

Contd.

• Regular examination of face must be done and

remedial measures must be taken to make it safe if

there is any doubt that a collapse could take place.

• Vocational training should be given to mine workers

to prepare them to face the challenges of mining.

• Emergency Response system and emergency action

plans are to be designed for mine.

Conclusion:

•Safety is the major concern in mining

industry.

•The hazardous risk of any industry should

be low to attain profits.

•In future, the Mining industry may be

fully modernized by advanced technology

like Automation and Remote

operations.

THANK YOU

Queries…