rrent page or check for previous versions at the Internet Archive. Yahoo! is not affiliated with the authors of this page or responsible for its content.
Microsoft PowerPoint - PO108 - Railroad A Series of Negative Exposure
A Series of Negative Exposure
Assessments Related to Asbestos
Assessments Related to Asbestos
Containing Components Still Used in
Containing Components Still Used in
Railroad Equipment Today
Railroad Equipment Today
-
-
PO108
PO108
-
-
American Industrial Hygiene Associations
66th Annual Conference and Exposition
May 15 2006, Chicago, Illinois
F.W. Boelter, CIH, PE
M.T. Weeks, CIH
C.E. Simmons, CIH
Boelter & Yates, Inc.
Park Ridge, IL Negative Exposure Assessment
Negative Exposure Assessment
29 C.F.R.
29 C.F.R.
§
§
1926.1101(f)(2)(iii)
1926.1101(f)(2)(iii)
Objective data
Objective data
product or material or activity
product or material or activity
cannot exceed TWA and EL (8hr TWA 0.1f/cc, 30min EL 1f/cc)
cannot exceed TWA and EL (8hr TWA 0.1f/cc, 30min EL 1f/cc)
work conditions having the greatest potential
work conditions having the greatest potential
Data collected during work operations
Data collected during work operations
closely resembling
closely resembling
employer's current operations
employer's current operations
processes
processes
type of material
type of material
control methods
control methods
work practices
work practices
environmental conditions
environmental conditions
Employee training and experience
Employee training and experience
<
<
current employees
current employees
Certainty employee exposures
Certainty employee exposures
<
<
TWA and EL
TWA and EL
TWA 0.1f/cc, EL 1f/cc
TWA 0.1f/cc, EL 1f/cc Assessment Strategy
Assessment Strategy
Field observation
Field observation
Interview individuals
Interview individuals
Observe work practices
Observe work practices
Select representative activities
Select representative activities
Evaluate exposures
Evaluate exposures
Use validated protocols
Use validated protocols
If conducting a chamber study
If conducting a chamber study
activities must representative of
activities must representative of
sequence
sequence
time and motion
time and motion
Data must be relevant,
Data must be relevant,
reproducible, and predictive.
reproducible, and predictive. Products, Materials, Activities
Products, Materials, Activities
Basic Characterization
Basic Characterization
Suspect materials
Suspect materials
Interested in components of equipment
Interested in components of equipment
Building materials already inventoried
Building materials already inventoried
Bulk analysis
Bulk analysis
When encountered
When encountered
By whom
By whom
Doing what
Doing what Inventory of Findings
Inventory of Findings
Materials
Materials
List of suspects was long
List of suspects was long
List of positive components was short
List of positive components was short
Visual identifiers were subtle to indistinguishable
Visual identifiers were subtle to indistinguishable
All components were non
All components were non
-
-
friable or encapsulated
friable or encapsulated
products
products
Anticipated fiber release potential was low
Anticipated fiber release potential was low NEA Candidates
NEA Candidates
Bakelite
Bakelite
Relay rack terminal strips
Relay rack terminal strips
Transformer terminal strips
Transformer terminal strips
Arc chutes
Arc chutes
Miscellaneous
Miscellaneous
Arc pads
Arc pads
Wire & cable
Wire & cable
Aerial cable
Aerial cable
Motor starter board wiring
Motor starter board wiring
Friction
Friction
Outboard brakes
Outboard brakes
Switch machine clutches
Switch machine clutches SEGs & NEAs
SEGs & NEAs
Bakelite
Bakelite
Task specific
Task specific
With other activities
With other activities
Friction
Friction
Field service
Field service
Shop rebuild
Shop rebuild
Motor Boards
Motor Boards
Field installed
Field installed
Shop rebuild
Shop rebuild
Cable
Cable
Outdoors
Outdoors
Indoors
Indoors Bakelite
Bakelite
Term used generically
Term used generically
Anything that looks like a molded product
Anything that looks like a molded product
Negative Materials
Negative Materials
Plastic or quasi
Plastic or quasi
-
-
plastic looking brown or black
plastic looking brown or black
Cut, sawn or snapped
Cut, sawn or snapped
Positive Materials
Positive Materials
-
-
30
30
-
-
65% chrysotile by PLM
65% chrysotile by PLM
Not actually
Not actually
Bakelite
Bakelite
Simply handled
Simply handled
Never cut, sawn or snapped
Never cut, sawn or snapped Bakelite
Bakelite Bakelite
Bakelite Bakelite
Bakelite
NEA
NEA Bakelite
Bakelite
NEA
NEA
3
3
COUNT
0
0.014
S.D.
< 0.006
0.037
MEAN
< 0.006
0.025
MINIMUM
< 0.006
0.053
MAXIMUM
NIOSH 7402 TEM (Asbestos f/cc)
8-Hour TWA Personal Samples
NIOSH 7400 PCM (Total f/cc)
8-Hour TWA Personal Samples
Statistical
Function
Full-Shift Personal Samples
20
20
COUNT
0
0.030
S.D.
< 0.045
0.074
MEAN
< 0.045
< 0.045
MINIMUM
< 0.045
0.139
MAXIMUM
NIOSH 7402 TEM (Asbestos f/cc)
30-Minute Personal Samples
NIOSH 7400 PCM (Total f/cc)
30-Minute Personal Samples
Statistical
Function
Excursion Limit (aka STEL) Personal Samples Friction Materials
Friction Materials
Generally holds something in place
Generally holds something in place
Brake shoes on motor drum
Brake shoes on motor drum
Solenoid released
Solenoid released
Often never replaced over life of machine
Often never replaced over life of machine
Field adjusted
Field adjusted
Possibly replaced but not relined
Possibly replaced but not relined
ND
ND
-
-
65% chrysotile by PLM
65% chrysotile by PLM
Clutch w/ fiber discs
Clutch w/ fiber discs
Always
Always
engaged
engaged
Slips to protect machine
Slips to protect machine
Maybe field replaced but never field serviced
Maybe field replaced but never field serviced
Open and close controller w/ arc pad (pad never replaced)
Open and close controller w/ arc pad (pad never replaced)
Shop rebuilt occasionally
Shop rebuilt occasionally
ND
ND
-
-
80% chrysotile by PLM
80% chrysotile by PLM Friction Materials
Friction Materials Friction Materials NEA 1
Friction Materials NEA 1 Friction Materials NEA 1
Friction Materials NEA 1
2
2
COUNT
< 0.000
0.006
S.D.
< 0.006
0.020
MEAN
< 0.006
0.016
MINIMUM
< 0.006
0.024
MAXIMUM
NIOSH 7402 TEM (Asbestos f/cc)
8-Hour TWA Personal Samples
NIOSH 7400 PCM (total f/cc)
8-Hour TWA Personal Samples
Statistical
Function
Full-Shift Personal Samples
8
8
COUNT
0.000
0.009
S.D.
< 0.045
0.050
MEAN
< 0.045
<0.045
MINIMUM
< 0.045
0.065
MAXIMUM
NIOSH 7402 TEM (Asbestos f/cc)
30-Minute Personal Samples
NIOSH 7400 PCM (total f/cc)
30-Minute Personal Samples
Statistical
Function
Excursion Limit (aka STEL) Personal Samples Friction Materials NEA 2
Friction Materials NEA 2 Friction Materials NEA 2
Friction Materials NEA 2
2
2
COUNT
0.002
0.011
S.D.
0.007
0.037
MEAN
<0.006
0.029
MINIMUM
0.009
0.044
MAXIMUM
NIOSH 7402 TEM (Asbestos f/cc)
8-Hour TWA Personal Samples
NIOSH 7400 PCM (total f/cc)
8-Hour TWA Personal Samples
Statistical
Function
Full-Shift Personal Samples
18
18
COUNT
0.000
0.015
S.D.
< 0.045
0.050
MEAN
< 0.045
<0.045
MINIMUM
< 0.045
0.106
MAXIMUM
NIOSH 7402 TEM (Asbestos f/cc)
30-Minute Personal Samples
NIOSH 7400 PCM (total f/cc)
30-Minute Personal Samples
Statistical
Function
Excursion Limit (aka STEL) Personal Samples Motor Control Board Materials
Motor Control Board Materials
In
In
-
-
Field, replace entire panel
Field, replace entire panel
In Shop, scavenged for parts
In Shop, scavenged for parts
Handle backing board
Handle backing board
75% chrysotile by PLM
75% chrysotile by PLM
Replace wiring
Replace wiring
Insulation 35
Insulation 35
-
-
55% chrysotile by PLM
55% chrysotile by PLM
Handle arc chutes
Handle arc chutes
ND
ND
-
-
50% chrysotile by PLM
50% chrysotile by PLM Motor Control Board Materials
Motor Control Board Materials Motor Control Board Materials
Motor Control Board Materials
3
3
COUNT
0
0.002
S.D.
< 0.006
0.015
MEAN
< 0.006
0.013
MINIMUM
< 0.006
0.016
MAXIMUM
NIOSH 7402 TEM (Asbestos f/cc)
8-Hour TWA Personal Samples
NIOSH 7400 PCM (Total f/cc)
8-Hour TWA Personal Samples
Statistical
Function
Full-Shift Personal Samples
14
14
COUNT
0
0.003
S.D.
< 0.045
0.046
MEAN
< 0.045
< 0.045
MINIMUM
< 0.045
0.053
MAXIMUM
NIOSH 7402 TEM (Asbestos f/cc)
30-Minute Personal Samples
NIOSH 7400 PCM (Total f/cc)
30-Minute Personal Samples
Statistical
Function
Excursion Limit (aka STEL) Personal Samples Cable Materials
Cable Materials
Aerial Cable
Aerial Cable
Woven cloth
Woven cloth
Manipulate, cut, strip
Manipulate, cut, strip
No visual differences between positive and negative
No visual differences between positive and negative
Multiple l