U.S. Department of
Labor
|
Mine Safety and Health Administration
201 12th Street South, Suite 401
Arlington, VA 22202-5450
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ISSUE DATE: 08/27/08
LAST VALIDATED: 03/31/2021
PROGRAM INFORMATION BULLETIN NO. P08-19
FROM: KEVIN G. STRICKLIN 
Administrator for
Coal Mine Safety and Health
SUBJECT: Re-Issue of P01-4 - Hoist Examination and
Safety Test Requirements
Who needs this
information?
This information bulletin applies to coal mine
operators, independent contractors, and Coal Mine Safety and Health (CMS&H)
inspection personnel.
What is the
purpose of this program information bulletin (PIB)?
This bulletin reminds the coal mining industry of
the required examinations and tests of hoist equipment safety devices. Improper tests and examinations could lead to
a potential safety hazard.
Information
Mine operator compliance with the examination and
test standards can detect unsafe conditions and lead to their prompt
correction. This bulletin clarifies coal
mine operators' compliance responsibilities for examining, testing, and
maintaining equipment used to transport persons under the applicable 30 C.F.R. §§75.1400
and 77.1400.
30 C.F.R. §75.1400(c)
Section 75.1400 (c) requires that cages, platforms,
or other devices used to transport persons in shafts and slopes shall be
equipped with safety catches or other no less effective devices approved by the
Secretary that act quickly in an emergency. Such catches or devices shall be tested at least once every two months.
Other no less effective devices referred to in this
section include the overspeed safety devices installed on the hoist man-trip
brake car to act quickly in an emergency. Overspeed devices are electro/mechanical devices installed to prevent
overspeed in the event of a brake failure on the hoist or a hoist rope failure.
The overspeed devices can either be centrifugal or magnetic motion type.
30 C.F.R. §75.1400(d)
Section 75.1400(d) requires that hoisting equipment
used to transport persons, including elevators, shall be examined daily.
30 C.F.R. §75.1400(e)
Section 75.1400(e) requires that when persons are
transported into or out of a mine by a hoist, a qualified hoisting engineer
shall be on duty while any person is underground. No such engineer, however, shall be required
for automatically operated cages, platforms, or elevators.
30 C.F.R. §75.1400-1
Section 75.1400-1 requires that brakes on hoists
used to transport persons shall be capable of stopping and holding the fully
loaded platform, cage, or other device at any point in the shaft, slope, or
incline.
30 C.F.R. §75.1400-2
Section 75.1400-2 requires that "A record shall be
made in a book of the tests, required by 30 C.F.R. 75.1400, of the safety
catches or other devices approved by the Secretary. Each entry shall be signed by the person
making the tests and countersigned by a responsible official."
30 C.F.R. §§75.1400-3(b) and
77.1403
Section 75.1400-3 (b) requires a daily examination
of hoists and elevators that include, but are not limited to, the following:
1.
an
examination of the rope fastenings for defects;
2.
an
examination of safety catches;
3.
an
examination of the cages, platforms, elevators, or other devices for loose or
missing or defective parts;
4.
an
examination of head sheaves to check for broken flanges, defective bearings,
rope alignment, and proper lubrication; and
5.
an
observation of the lining and all other equipment and appurtenances installed
in the shaft.
Section 77.1403 requires a daily examination of
hoists and elevators that include, but is not limited to, the following:
1.
an
examination of the rope fastenings for defects;
2.
an
examination of head sheaves to check for broken flanges, defective bearings,
rope alignment, and proper lubrication; and
3.
an
examination of the automatic controls and brakes required under Section 77.1401.
30 C.F.R. §77.1401
Section 77.1401 requires that hoists and elevators
shall be equipped with overspeed, overwind, and automatic stop controls and
with brakes capable of stopping the elevator when fully loaded.
30 C.F.R. §75.1400-4
Section 75.1400-4 requires that at the completion
of each daily examination required by 75.1400, the person making the
examination shall certify, by signature and date that the examination has been
made. If any unsafe condition is found
during the examination required by 75.1400-3, the person conducting the
examination shall make a record of the condition and the date. Certifications and records shall be retained
for one year.
Overspeed devices on the brake car can either be
centrifugal or magnetic motion type. Both types can be tested bimonthly by one of the following methods:
Test Method 1
1 Lift brake car until the wheel units that
drive the overspeed devices are off the rail.
2. Securely block the brake car to prevent
movement.
3. Drive the wheel units that are connected
to the centrifugal overspeed devices to 115% of rated hoist rope speed to
verify the overspeed operation and activation of the safety catches. Verify
with a speed indicator, set to feet per minute that both overspeed devices
cause the overspeed safety catches to operate within their specified range.
Test Method 2
1. Load brake car with rockdust or sand bags
to simulate normal mantrip load capacity.
2. Disable overspeed device on the main
hoist.
3. Run loaded brake car down the slope at
115% of rated rope speed. Verify that
each overspeed device independently activates the safety catches and causes the
brake car to stop and hold the fully loaded brake car.
4. Check the hoist depth indicator speed
(feet per minute) to determine that the overspeed devices activated the safety
catches within their specified range.
5. When brakes are applied with brake car on
the slope, do not release the brakes unless the hoist rope is tight or the
brake car is held by other means.
6. Push the off switch on the brake car to
release the brakes.
In addition, the manufacturer of the brake car
recommends a daily examination check list for the brake car that includes the
following:
1. Check brakes to see that they are
adjusted to 1/4" to 3/8" above the rail and that they move freely on
their supports.
2. Check the battery charge with a
hydrometer. A fully charged battery will
be between 1.225 and 1.260 specific gravity in each cell.
3. Check condition of V-belts driving the
centrifugal overspeed switches, and ensure that belt tightener moves freely
(some brake cars have magnetic motion overspeed detectors).
4. Manually close each centrifugal overspeed
switch independently and activate the safety catches.
5. Push the off button to release brakes.
6. The circuit breaker mounted vertically on
the control panel provides short-circuit protection. This should be closed at all times.
7. Close the circuit breaker next to the
ammeter. The red light will go on and
the car is ready for operation. This
switch should be opened when the brake car is not used for extended periods of
time, but must be closed when charging the batteries.
8. Push the ON button to apply brakes. All brakes should go down on the rail and the
ammeter should indicate 85 to 90 amps. The white light should be on.
9. Push the OFF button to release the
brakes.
10. Push the UP button to establish the
roll-back circuit. The green light will
go on. Move car inby and see that
brakes are applied.
11. Push the OFF and DOWN buttons to release
the brakes and deenergize the roll- back circuit.
12. Once the cars have been put in service at
the start of the shift, the only attention needed is to push the UP button
before starting up the slope and the DOWN button before going down.
13.
If
the control circuit fuse blows or the panel mounted circuit breaker opens, the
brakes automatically will be applied through the fail-safe circuit. The white light will be on and the ammeter
will not show discharge. After removing
slack from the rope, open the circuit breaker next to the ammeter to release
the brakes, and correct the faulty circuit.
Background
A double fatality occurred in an underground coal
mine on August 28, 2000, when a hoist rope used in a service slope of an
underground coal mine failed, resulting in the death of the miners. The two miners were riding the mantrip down
the slope when the rail-mounted hoist-operated mantrip ran away, breaking the
wire rope. The overspeed devices on the
brake car did not function to stop the run-away mantrip. The investigation revealed that the overspeed
devices on the brake car had not been properly tested and the centrifugal
switches were out of adjustment.
Is this
information bulletin on the Internet?
This information bulletin may be viewed on the
Internet by accessing the MSHA home page (http://www.msha.gov) and
then choosing Statutory and Regulatory Information, Program Information
Bulletins, and 2008 Program Information Bulletins.
What is the
authority for this bulletin?
The Federal Mine Safety and Health Act of 1977; as
amended, 30 U.S.C. §801 Et Seq; 30 C.F.R. §§75.1400 and 77.1400
Issuing Office
and Contact Person
Mine Safety and Health Enforcement, Division of Safety
Rodney Adamson, (202) 693-9549
E-mail: adamson.rodney@dol.gov
Who will receive
this bulletin?
Program Policy Manual Holders
Coal Mine Operators
Independent Contractors
Special Interest Groups
Miners' Representatives