Implementation of MINER Act for Communication and Tracking Using MSHAs Program Policy Letter PPL P09

1
Implementation of MINER Act for Communication and
Tracking Using MSHAs Program Policy Letter (PPL)
P09-V-01 as Guidance

• Salwa El-Bassioni
• Electrical Engineer
• May 14, 2009

2
MINER Act RequirementsJune 15, 2006

• A redundant means of communication with the
  surface, such as secondary telephone or
  equivalent two-way communication.
• Above ground personnel to determine the current,
  or immediately pre-accident location of all
  underground personnel.

3
MINER Act RequirementsJune 15, 2009

• Post-accident communication between underground
  and surface personnel via wireless or alternative
  to wireless, PPL provisions.
• Electronic tracking system to determine location
  of persons trapped underground

4
Untethered Devices

• One device for each group of miners working or
  traveling together.
• One device for any miner working or traveling
  alone.
• How many would we need on a working section?
• One device for each group working or traveling
  together and one device for each miner working or
  traveling alone. For example on advancing
  sections, each CM operator, roof bolter crew, and
  scoop operator would need their own device.

5
Continuous Miner Section
6
Longwall
7
Coverage for Two-Way Communications

• Throughout the working section.
• Miners inby the loading point are able to
  communicate with the surface.
• Continuous in each escapeway.
• Primary and secondary.
• 200 foot zone inby and outby strategic areas.
• Strategic areas where miners are normally
  required to work or likely to congregate in an
  emergency.

8
Coverage ComplianceMesh System

• Components of a mesh system
• Untethered devices (radios).
• Nodes (wired/wireless or both).
• Antennas
• Power supplies.
• Gateway nodes, hub or controller on the surface.
• Communication facility on the surface for
  monitoring network.
• Note power supplies used in areas where
  permissible equipment is required must be IS or
  in X/P enclosures.

9
Mesh System
If a node fails the system reconfigures itself
and determines a new route
10
Mesh System
A power supply and/or battery backup required at
each node
Power Source
11
Two-way Communication Coverage
12
Two-Way Communications Longwall
13
Coverage Compliance LF System

• Components of a Leaky Feeder
• UHF and VHF Radios
• Power supplies
• UHF amplifier
• VHF amplifier
• Surface base stations
• Splitters
• Antennas
• Termination units
• Note power supplies used in areas where
  permissible equipment is required must be IS or
  in X/P enclosures.

14
Miner 1 Transmitting
Leaky Feeder
Functions as a power line, communications link,
and a distributed antenna
Miner 2 Receiving
15
Leaky Feeder CM Section
16
Leaky Feeder Longwall
17
Coverage ComplianceMedium Frequency (MF) System

• Components of MF system
• Conductors in a mine (track, metal pipes..)
• Hand held radios
• Base transmitter (transceiver in central area)
• Repeaters (transfers frequency)
• Node (repeater used in a network)

18
Medium Frequency (MF) Radio Communications

• Doesnt require special cable.
• Radio signal couples to other conductors to
  increase range.

19
Medium Frequency Repeater

• UHF signal is converted to/from MF signal

• MF Signal is carried by un-powered conductive
  infrastructure in mine

20
Survivability

• Redundant pathways to surface
• One system with two or more pathway to the
  surface.
• Two or more systems installed in two or more
  entries and different pathways to the surface.

21
Survivability Redundancy
One system, two Pathways
22
Primary Base Station
Secondary Base Station
Overland Link
Mine Shafts
Leaky Feeder
23
One Node-Based Mesh System with two pathways
24
Two Leaky Feeder systems in multiple entries
Antenna
UHF LF Cable - Trunk 2
Escapeway
Belt
Track
UHF LF Cable - Trunk 1
25
Coverage extension using low-cost cables and
antennas
Antenna
Low-cost LF Cable
Escapeway
Belt
Track
UHF LF Cable
26
Electronic Tracking Coverage

• Types of tracking
• Zone-based
• RFID tags and readers
• RSSI -based
• Using nodes as those from communication system.

27
Conventional Tracking
Miner wears a tag Radio frequency ID
(RFID) Needs readers of tags
28

• Operation of conventional RFID
• Reader senses tags that are within range
• Tag transmits a unique ID
• Detected tag IDs are sent to the surface

Miner B
Tag
Miner A

• Tag location is associated with the readers
  known location and displayed on the tracking
  computer

RFID Reader
29

• Operation of reverse RFID
• Tags transmit RFIDs
• Reader receive RFID from tag(s)
• RFID from reader tag transmitted to comms system

Miner B

• Comms system relays reader and tag information to
  surface
• Tracking computer calculates and displays reader
  positions

Miner A
RFID Reader
Leaky Feeder
Tag
30
Electronic Tracking Guidance

• Coverage in working section within 200 feet
• Readers or nodes are 400 feet apart.
• Coverage in escapeways
• Readers or nodes every 2000 feet
• Coverage in strategic areas
• Within 200 feet of where miners are normally
  required to work or likely congregate in an
  emergency.
• Belt drives, loading points, SCSR caches, etc.

31
RSSI-Based Tracking(Node-based Systems)

• Error difference between estimated and actual
  location.
• MSHA expects that errors in tracking locations
  may exist and will work with mine operators until
  compliance with the MINER Act is gained.

32
Zone-Based Tracking(Reader-based
Systems)Conventional and Reverse RFID

• Error difference between reported and actual
  position
• Accuracy of tracking is affected by
• tracking system update rate
• motion of miners
• reader or tag spacing
• Interference

33
Electronic Tracking Coverage
34
Electronic Tracking Coverage Longwall
35
Emergency Response Plan ERP

• No later than June 15, 2009 the ERP must, among
  other things, provide for
• Post accident two-way communications
• Electronic tracking

36
Content of ERP

• ERP will be reviewed on a mine-by-mine bases.
  Reviewers will be evaluating the following
• Wireless communication systems
• Type of system (LF, mesh, Wi-Fi, MF)
• Survivability, how it provides redundancy

37
Content of ERP(continued)

• Provisions for untethered devices
• Accessibility to miners
• Text, voice or both
• Standby power
• Approved (approval )

38
Content of ERP(continued)

• Provisions for infrastructure
• Type of components (LF, nodes, AP)
• Approved components (approval if applicable)
• Location in the working section
• Location in escapeways
• Location relative to strategic areas
• Power supply evaluation if applicable.

39
Content of ERP(continued)

• Electronic tracking system
• Type of system, reader or node-based
• Location of tags
• Location of readers or nodes in working section
• Location of readers or nodes in escapeways
• Location in strategic areas
• Vendor if known
• Model number if known
• Approval number if known
• Standby power for infrastructure
• Standby power for tags

40
Content of ERP(continued)

• Surface provisions to address
• Standby power
• Communication with and monitoring of undergrond
  personnel
• Uniquely identifying each miner
• Location data is associated with time
• How long the data is stored
• Frequency of updating location data

41
Content of ERPContinued

• Maintenance provisions
• Manufacturer plan
• Restoring backup power
• Examination provisions
• Weekly examination for infrastructure
• Daily examination of tags and radios
• Backup plans
• Communication system fails
• Tracking system fails

42
Summary

• Survivability can be achieved by hardening the
  system or providing redundancy.
• One way to provide redundancy is to mix and match
  a primary (LF or mesh system) system with a
  secondary system ( MF or TTS).
• Error factors depend on system design, system
  installation, and computer algorithm being used.

43
Any Questions?