26---Wednesday---Oral Questions 3---1st Feb 2016 uploaded.

Question 1

What must a deputy look at, do and record, before going underground?

Answer 1

Read & Sign previous shift report
Take note of Temperature and barometric pressure as well as the trend up down steady
Take note of Mine pressure (collar pressure) and Fan quantities.

Question 2

What do you do when intersecting a borehole? What are the Dangers,
SOPs,
JSAs
explain the procedures.

Answer 2

Assume they are all pressurised and full of gas, There is

increased risk of ignition,
asphyxiation
Water inundation,
local strata failure.

Controls:

Permit to mine notice,
gas drainage permit notice,
gas drainage hmp.

Comply with the BIN (borehole intersection notice) when within 10m of the hole.
No one on the bolting platforms,
erzc To implement fricitional ignition procedures,
check that the hole has been disconnected from the range and left open,
grout in a 1m stand pipe,
install a dropper,
record all findings,
in the longwall stop check the hole for ch4, slow down when passing over hole.

Question 3

Explain the effects of these gases on man?
ch4
co2
co

Answer 3

CO - Carbon Monoxide

A highly insidious gas, displacing oxygen in the blood. Instead of taking oxygen to the organs it takes CO.

Effects are headaches, tension in forehead, nausea, weakness, rapid pulse legal limit 30ppm. SG0.97.
Explosive 12.5% to 74%

CO2 - Carbon Dioxide

In high concentrates acts as a stimulant on the central nervous system, however, excessive concentrations depress the CNS and respiratory systems causing unconsciousness, respiratory arrest and death.

2% gives a 50% increase in respiration.
5% gives 300% increase in respiration rate,
headaches and nausea. Legal limit 1.25%. SG1.53

CH4 - Methane
Not toxic, but will not support life; in concentrations it has a slight anesthetic effect. SG 0.55. Explosive 5% to 14%

Question 4

A miner is having problems with long tails on bolts, only on his side. What roof conditions would you expect to see?

Answer 4

Structures in the roof,

mud/clay in fines from drill steel wash,

Question 5

How can you tell weight is coming onto the roof?

Answer 5

Guttering along rib side on the roof.
Ribs fretting.
Roof cracking,
stone/dust falling,
roof washers/plates bending, read tell tails.
Cracks visually appearing and opening up.

Question 6

Mine pressure on fan and barometric pressure why are these important and

What do they tell a deputy?

Answer 6

The mine pressure is measured in Pascals
The mine main fan creates a low pressure at the fan which creates a pressure differential between the intake and return This causes the air to move as the air moves towards the low pressure.

For a lower collar pressure in the mine than a normal reading. This could mean a ventilation stopping has been knocked over or damaged. and the air is short circuiting.

High pressure could mean a roof fall or build up of water, creating resistance in the mine roadway.

Barometric pressure is measured in hectopascals,
Air will move from a high pressure zone to a low pressure zone,
This effects the mine because as the pressure increases or rises the goaf or goaves breath in,
and when the atmospheric pressure decreases or falls the goaves breath out, potentially contaminating the ventilation of the mine.

Question 7

What are the Frictional Ignition Procedures at your pit?

Oaky pit procedures.

Answer 7

Generally caused by striking Quartz or pyrite
Development.

Follow TARPs, 
SOPs, 
Hazard Plan, 
Controls, adequate ventilation minimum 8m3/s,
sufficient water/sprays 900kpa, 
correct picks check every 5m, 
CH4 monitoring Alarm/ heads 1% trip, power 1.25%, 
fire fighting equipment, 
Stonedust incombustibles 85%, 
no back racking the floor/roof, 
ducting to be kept within 4m of face, 
follow Frictional Ignition Check List, 
Training.

Longwall

Follow TARPs, 
SOPs, 
Hazard Plan, 
Controls, adequate ventilation minimum 30m3/s, 
limit trimming roof and floor, 
adequate water/ sprays 15 bar water flow switches, suitable picks,
CH4 monitoring face side alarm, 1% trip power, 2% goaf side alarm 0.55%, trip heads 0.7% trip power 1.25%, suitable fire fighting equipment, 
Training. 
Maintain brattice wing between rib and #1 shield, 
check wick affect every 10 shields, 
sample goaf stream every shift, 
limit shearer speed, 
incombustibles 85%, 
Frictional Ignition Check List.
Goaf stream 4%. 
Mg/TG alarm 1% trip 1.25% Mg
C0 alarm.

Question 8

Panel Power has tripped because of CH4.

A What amount of air is required to run both fans?
B. Where would you do an air survey?
C. How do you degas both headings?

Answer 8

A. The open circuit capacity of each fan in operation and 30% of the open circuit capacity of the largest fan in operation in the panel.

B. Outbye the last completed c/t.

C. Vent Survey,
inspect the face area
tube line tubes,
rubbers
end caps,
20m around the fan for less than 1.25% CH4,
open the degassing box
inspect in the fan,
start the fan and monitor for CH4,
then slowly close the degassing box continually checking the level of gas,
once fully closed inspect the face areas.

Question 9

What would you find in the Crib Room?

Answer 9

Signs
clearly visible (lettering double sided),
mounted correctly,
clean and as per correct colour

Signs located in this area are

first Aid,
Crib Room,
Telephone sign

Communication

Phone
DAC
Current Phone List
test emergency number Emergency procedure sticker is on phone, number clearly displayed on phone.

Question 10

As the Deputy, what should you do if there is a roof fall in t/g and little or no ventilation?

Answer 10

Check ventilation,
stop production
remove men and power,

if ventilation inadequate.
Notify Control, Shift Supervisor,
use risk logic.
Support the face area.
Run AFC, may cleared enough stone to get ventilation . Support roof,
cut into it to remove stone and create airway.

Question 11

Explain step by step all areas to re-ventilate a longwall?

Answer 11

Do an inspection of the l/w. 
Check brattice up at #1 chock.
Check ventilation quality 
GB gas outbye the t/g drive 20m. 
Check the goaf stream. 
Calculate the air velocity in m/s, traverse the roadway with an anemometer for 1 minute. 
Temperature wet dry 
supports, 
power up the face. 
ASK FOR HELP IF REQUIRED.

Question 12

Could there ever be another Moura?

Answer 12

I hope not.
Since then we have a new ACT and Regulations.
We use Risk Logic,
People are better trained in identifying Spontaneous combustion.
NERZ/ERZ boundaries.
No longer use flame safety lamps.

Question 13

What is the minimum water pressure underground?

Answer 13

480kpa

Question 14

Name the inert gases?

Answer 14

Nitrogen, 
Argon, 
CO2, 
Neon, 
Krypton

Question 15

Name the toxic gases?

Answer 15

Carbon Monoxide,
Oxides of Nitrogen,
Hydrogen, Sulphide,
Carbon Dioxide >10%

Question 16

What is the Risk Assessment Process?

query 21XXX

Answer 16

The Act requires that 
risk management elements and practices, operating systems are in place, 
cross section of the workforce, 
identify analyze and assess risk, 
with regard to the likely hood 
and severity of injury. 
Risk Assessment Matrix. Rating 
1/5  low, 
6/9 Med, 
10/25 high.

Question 17

What is a Single Entry Drive?

Answer 17

A single drive longer than 350m.

Question 18

What does a Barometer measure?

Answer 18

Air pressure in Hectopascals.

Mine Pressure is measured in kpa.

Question 19

What affects the Longwall Panel Goaf Stream?

Answer 19

Goaf stream are found using hand and PGD brattice at #80 chock (COOK Colliery)
frictional ignition. 
caving characteristics 
rate of retreat, 
ingress of paths from the surface, 
goaf wells, 
conduits or cracks. 
Seal breach.

Question 20

What is the composition of air?

Answer 20

O2 - 20.93%,
N2 - 78.11%,
CO2 - 0.03%,

inert gases 0.93 are
argon,
neon,
krypton

Question 21

What does a Risk Assessment Matrix show?

query 16XXXX

Answer 21

Consequence,
likely hood,

hierarchy of control, 
elimination, 
substitution, 
engineering/isolation, 
administration/training, 
PPE, 
most effective to least eefective.

Rating - 1 to 5 = low,
6 to 9 = medium,
18 to 25 = high.
Anything above 9 is reported to the manager for action.

Question 22

What is Spontaneous Combustion?

Answer 22

Carbon in coal reacts with oxygen,
this is called oxidation, in which the oxidation produces heat.
If the heat is not dissipated the oxidation process will increase,
the rate of oxidation accelerates rapidly with increasing temperature, possibly escalating into a spontaneous combustion event.

Factors which assist are coal properties, 
coal type 
rank, 
particle size, 
geological conditions, 
poor housekeeping, 
mining ventilation techniques.

Question 23

What are the physical indicators of Spontaneous Combustion and temperatures in degrees centigrade?

Answer 23

Sweating --100c
Slight Smell --125c
Heat --150c
Haze --200c
Smoke --300c
Fire --550c

Question 24

What happens to the rate of oxidation when the temperature increases by 10 degrees celsius?

Answer 24

The rate of oxidation doubles.

Question 25

What are the different types of inertisation techniques available at your mine?

Answer 25

Inertisation

gag–boiler produces predominantly nitrogen.

Question 26

Explain the Goaf Management at your mine?

Answer 26

Brattice sail at #1 Chock;
build seals behind the wall ASAP after going past the cut through.
Keep the Longwall moving so airflow into the Goaf keeps moving away from the critical zone.
Keep the wall straight to assist with roof support.

Question 27

35kPa mains VCDs - How would you know if a VCD was being constructed properly?

Answer 27

There is no practical way to test the overpressure capacity of these devices underground. They are built to engineering specifications.

However there is a specification to follow during construction.

Question 28

What to the Regulations say a shotfirer must ensure delay detonators are not, when used in an ERZ1?

Answer 28

They must not be more than 250 milliseconds.

Question 29

Why do we use tungston carbide tips on cutting tools?

Answer 29

Because Tungston Carbide has the highest melting point of any non alloy metal at 3422 degrees celsius
The second highest of any other element behind carbon. This reduces pick wear and heat generation.

Question 30

What does Antitropal Ventilation mean?

Answer 30

Antitropal means the ventilation is the opposite of coal flow

Question 31

What does Homotropal Ventilation mean?

Answer 31

Homotropal ventilation means in the same as the coal flow.

Question 32

If the main fan trips, does the underground power have to trip?

Note
Gary to end with Regs on Aux fansXXXXXXXXXXXX

Answer 32

New legislation recognises that there is no immediate danger when a main fan stops and there may be critical activities taking place underground that could be jeopardised ( e.g. Pillar extraction with a continuous miner, shearer in an exposed situation, critical pumping). In now, not tipping power to the mine, the Boundary Monitors are a line of defence to protect against flammable gas accumulation in the face area and migration outbye.

Question 33

Why do we separate the conveyor system?

Answer 33

Part of the fire management strategy legislation requires us to separate intake airways as far as practiable from all other road ways, to be free from risk of fire. If a fire happens in a conveyor roadway then the primary escapeway will be safe to travel

Question 34

Can you have a pump running in the main stub if the power is off?

Answer 34

yes with Monitoring equipment on fan,

methane detector
CO detector
thermal trip
vibration equipment.