WORKING IN
SF6 ATMOSPHERES
GUIDE
WORKING IN SF6 ATMOSPHERES
© Copyright 2003
All rights reserved.
Reproduction of this document in whole or in part by any
means is prohibited, unless authorized in writing by:
ATCO Electric Operations
Health, Safety & Environment
10035 - 105th Street
Edmonton, Alberta Canada T5J 2V6
Phone: (780) 420-4134
Fax: (780) 420-5410
November 2003
© Working in SF6 Atmospheres
TABLE OF CONTENTS
SECTION 100: HOW TO USE THIS DOCUMENT
101 Introduction..........................................................................1
102 Purpose.................................................................................1
103 Scope ....................................................................................1
104 Additional Resources ...........................................................2
105 Definitions............................................................................2
SECTION 200: COMPLETING THE CODE OF PRACTICE FORM
201 Identifying an SF6 Atmosphere............................................5
A. Identifying SF6 and/or its Byproducts.............................5
202 Respirator Selection .............................................................8
203 Health Surveillance ..............................................................8
204 Respirator Fit Testing...........................................................9
205 Training ..............................................................................10
A. SF6 Training..................................................................10
B. Respirator Training .......................................................10
206 Before-Use Respirator Inspection ......................................10
207 Emergency Response Plan .................................................11
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Page i
WORKING IN SF6 ATMOSPHERES
SECTION 300: ENTERING AN SF6 ATMOSPHERE
301 Entry Requirement Verification......................................... 13
A. Code of Practice Review ............................................ 13
B. Air Supply Verification ............................................. 13
302 Respirator Safety Procedures ............................................ 14
A. Before Entering an SF6 Atmosphere .......................... 14
B. While Working in SF6 Atmosphere............................ 14
C. Terminating Respirator Use........................................ 16
303 Emergency Procedures for Respirator Malfunction .......... 16
SECTION 400: DOCUMENTATION
401 Record Keeping ................................................................. 19
APPENDICES
Appendix A: Positive Pressure User Seal Check using Tight
Fitting Elastomeric Face-pieces/Qualitative and
Quantitative Respirator Fit Tests .......................... A-1
Appendix B: Training Requirements for Respirator Users ........ A-2
Appendix C: SCBA Inspection Procedures................................ A-3
Appendix D: SCBA Inspection Record...................................... A-6
Appendix E: SCBA Donning Procedure.................................... A-7
Appendix F: Cylinder Replacement Procedure........................ A-10
Appendix G: SCBA Doffing Procedure ................................... A-11
Appendix H: Respirator Cleaning and Sanitation..................... A-13
Appendix I: Respirator Storage .............................................. A-14
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© Working in SF6 Atmosphere
SECTION 100:
HOW TO USE THIS DOCUMENT
101
Introduction
In the course of their work, Operations employees may be exposed to
atmospheres contaminated with sulphur hexaflouride (SF6) or its
byproducts.
Working in SF6 atmospheres requires the use of a respirator
equipped with an independent air supply, commonly referred to as a
supplied-air respirator or Self-Contained Breathing Apparatus
(SCBA). It is imperative that employees be fully trained and
equipped to identify and work safely in these atmospheres, and to
respond to any emergency situation.
102
Purpose
To provide standards and procedures for safe entry into an SF6
atmosphere requiring the use of supplied-air respirator or SCBA
(only).
103
Scope
This guide applies to all Operations employees who work with
equipment containing SF6 gas and SF6 byproducts.
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Page 1
WORKING IN SF6 ATMOSPHERES
104
Additional Resources
The following resources were used in developing this guide
and may be referenced by employees requiring more
information:
105
•
Alberta Occupational Health and Safety Act, Code and
Regulations;
•
CSA Standard Z94.4-02: Selection, Use and Care of
Respirators; and
•
CSA Standard Z180.1-00: Compressed Breathing Air
and Systems.
Definitions
Air – The respirable gas making up Earth’s atmosphere,
composed mainly of oxygen and nitrogen. Normal ambient
air contains an oxygen concentration of 20.8 per cent by
volume.
Compressed Breathing Air – Normal air that is processed
by a compressed breathing air system and that meets the
purity requirements of CSA Standard CAN/CSA Z180.1.
Confined Space – An enclosed or partially enclosed space
that:
•
Is not primarily designed or intended for human
occupancy except for the purpose of performing work;
•
Has restricted means of access and egress; and
•
May become hazardous to an employee entering due to
its design, construction, location or atmosphere, the
materials, substances or work activities within, or any
other hazards relating to it.
All confined spaces are considered potentially hazardous
unless proven otherwise.
Cylinder – A pressure vessel, as defined in CSA Standards
CAN/CSA-B339 and CAN/CSA-B340, forming an integral
part of the approved respirator.
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SECTION 100: HOW TO USE THIS DOCUMENT
Fit Test – The use of a qualitative or quantitative method to
evaluate the fit of a specific make, model and size of respirator on
an individual.
Gas – A substance that is in the gaseous state at ambient
temperature and pressure.
Hazardous Atmosphere – Any atmosphere that is oxygen
deficient, exceeds occupational exposure limits, presents a
fire/explosion hazard and/or contains an airborne toxic or diseaseproducing contaminant in concentrations deemed to be hazardous.
Qualitative Fit Test – A pass/fail test method that relies on the
subject’s sensory response to detect a challenge agent in order to
assess the adequacy of respirator fit.
Quantitative Fit Test – A test method that uses an instrument to
assess the amount of leakage into the respirator in order to assess
the adequacy of respirator fit.
Respirator – A device to protect the user from inhaling a
hazardous atmosphere. In the context of this guide, the term
“respirator” refers to a supplied-air respirator or Self-Contained
Breathing Apparatus (SCBA).
Safety Watch – Employee(s) required to stand by outside a
confined space and remain in constant communication with
employee(s) inside the confined space.
Sanitation – The use of an accepted disinfectant product to clean
the surfaces of an inanimate object in order to mitigate or prevent
the transmission of disease to humans.
Self-Contained Breathing Apparatus (SCBA) – An approved
respirator that has a portable supply of compressed breathing air
and is independent of the ambient atmosphere; this includes both
open-circuit and closed circuit respirators.
Supplied-Air Respirator – An approved respirator and air supply
hose with a hood/helmet, a tight-fitting face-piece or a loose-fitting
face-piece/visor that is supplied with compressed breathing air
from a compressed breathing air system.
Vapour – The gaseous state of a substance that is solid or liquid at
ambient temperature and pressure.
November 2003
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Page 3
SECTION 200:
COMPLETING THE CODE OF
PRACTICE FORM
A Respirator Code of Practice form must be completed by the
employee and signed by the supervisor (or the existing approved
Code of Practice form reviewed) before every use of a respirator.
Refer to the Safety Standards Manual, Section 402.
201
A.
Identifying an SF6 Atmosphere
Identifying Sulphur Hexaflouride (SF6) and/or its
Byproducts
SF6 is used extensively in the electric industry, particularly
in circuit breakers and switch gear. However, a release of
SF6 gas can create one of the most hazardous atmospheres
that may be encountered by an electric utility employee.
ANY concentration of SF6 gas byproducts inside a
substation building or in a substation yard is considered
a hazardous atmosphere. See the Material Safety Data
Sheet for SF6 and Tables 201-1 and 201-2 for exposure
levels and additional toxicity information.
To identify substations where SF6 equipment is located,
access MAXIMO® and the applicable Single Line Diagram
(SLD), and confirm with the electrical technologist
responsible for the substation.
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WORKING IN SF6 ATMOSPHERES
Table 201-1: SF6 Byproducts
Chemical
Formula
HF
SOF2 (SF4)
SOF4
SiF4
S2F10 (SF5)
SO2F2
SO2
CuF2
AlF3
WF6, WO3
Chemical Name
Chemical
Abstract Service
Registry
Number*
Hydrogen fluoride
Thionyl sulphide
(sulphur
tetrafluoride)
Sulphur tetrafluoride
oxide
Silicon tetrafluoride
Disulphur
decafluoride
Sulphuryl fluoride
Sulphur dioxide
Copper Flouride
Aluminum Fluoride
Tungsten
compounds
7664-39-3
7783-42-8
(7783-60-0)
Percent by
Volume
(laboratory
conditions)
1.0
0.5
13709-54-1
0.085
7783-61-1
5714-22-7
0.085
0.025
2699-79-8
7446-09-5
0.006
0.002
For additional information on these and other chemicals, visit
CCINFO web at http://ccinfoweb.ccohs.ca/, an Internet resource
hosted by the Canadian Centre for Occupational Health and Safety.
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SECTION 200: COMPLETING THE CODE OF PRACTICE FORM
Table 201-2: Exposure Limits – SF6 and Byproducts
Chemical Name
Permissible Exposure
Limit – Ceiling
Sulphur hexafluoride SF6
1 ppm=5.98 mg/m3
Hydrogen fluoride HF
1 ppm= 2.2mg.m3 @25C@mw 54
Thionyl sulphide
(sulphur tetrafluoride) SOF2 (SF4)
1000 ppm
6000 mg/m3
3 ppm
Sulphur tetrafluoride oxide SOF4
0.1 ppm
0.44 mg/m3
0.1 ppm
Silicon tetrafluoride SiF4
1 ppm=2.5 mg/m3 (as Fluorides)
Disulphur decafluoride S2F10 (SF5)
1 ppm=10.39mg/m3
Sulphuryl fluoride SO2F2
1 ppm=4.18mg/m3
Sulphur dioxide SO2
1 ppm=5.89mg/m3
Sulphur tetrafluoride SF4
1 ppm=4.42 mg/m3
November 2003
© Working in SF6 Atmospheres
Permissible Exposure
Limit – Time Weighted
Average
1000 ppm
3 ppm
Short Term Exposure
Limit
Threshold Limit
Value
1250 ppm
7467 mg/m3
6 ppm
1000 ppm
3 ppm
Threshold Limit
Value – Ceiling
3 ppm
2.3 mg/m3
1 ppm
0.3 ppm
1.3 mg/m3
0.01 ppm
0.25 ppm
5 ppm
20 mg/m3
2 ppm
5 mg/m3
0.1 ppm
5 ppm
20 mg/m3
2 ppm
0.1 ppm
10 ppm
42 mg/m3
5 ppm
13 mg/m3
0.6 ppm
0.1 ppm
0.5 ppm
0.01 ppm
5 ppm
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2 ppm
2 ppm
0.1 ppm
0.1 ppm
WORKING IN SF6 ATMOSPHERES
Safety Standards Manual, Section 402: Working in
Hazardous Atmospheres
Confined Space Entry Guide
202
Respirator Selection
See Table 202-1, and refer to the Tool Catalogue on the
Intranet for equipment approved for use by Operations
employees.
203
Health Surveillance
All employees must complete a health screening report and
have it signed by their supervisor before using a respirator.
(Refer to the Safety Standards Manual, Section 402.)
Employees assigned a supplied-air respirator or SCBA will
be required to undergo a health screening and medical
assessment by the occupational health nurse or physician:
•
Before initial use of the respirator;
•
Thereafter as recommended the occupational health
nurse or physician, and
•
Whenever the employee has concerns about their
medical fitness to use a respirator or concerns that their
use of a respirator is causing adverse health effects.
All medical information will be treated as strictly
confidential.
The occupational health nurse or physician will provide the
manager with their written professional opinion that the
employee is:
Page 8
•
Medically fit to use the selected respirator;
•
Medically fit to use the selected respirator with
restrictions; or
•
Not medically fit to use the selected respirator.
November 2003
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SECTION 200: COMPLETING THE CODE OF PRACTICE FORM
204
Respirator Fit Testing
Respirator fit testing is essential to select the specific model
and size of face-piece appropriate for the individual user,
and to ensure a comfortable fit and effective seal.
1.
A qualitative or quantitative fit test must be conducted:
•
Before initial use of the respirator and at least every
2 years; however it is recommended that fit tests be
conducted annually;
•
Following dental surgery; and
•
If weight gain or loss by the user exceeds 10 per
cent.
Refer to Appendix A for fit testing.
2.
The respirator fit test can be conducted only if the user
is clean-shaven.
3.
If other personal protective equipment (e.g., eye, face,
head and hearing protectors) is required to be worn
when using the respirator, or if the user normally wears
eyeglasses, these items must be worn during respirator
fit testing to ensure they are compatible and do not
break the seal.
4.
Records must be kept of all fit tests, including:
•
Name of the employee being fitted;
•
Type of test performed;
•
Make model and size of the respirator fitted;
•
Date of the fit test;
•
Results of the fit test; and
•
Name of the person conducting the fit test.
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Page 9
WORKING IN SF6 ATMOSPHERES
205
A.
Training
SF6 Training
Employees who maintain SF6 equipment must:
B.
•
Complete routine maintenance training for SF6
equipment;
•
Become familiar with this guide, SF6 training manuals
and related materials; and
•
Use their assigned respirator at least every six months to
maintain their familiarity with the equipment.
Respirator Training
All employees assigned a respirator or assigned standby or
emergency rescue duties in SF6 atmospheres must be trained
in the proper use and maintenance of the selected respirator.
Other training may also be required (e.g., Standard First
Aid, CPR, training on test instruments).
Refer to the training checklist provided in Appendix B to
identify minimum training requirements to meet CSA
standard Z94.4-02
206
Before-Use Respirator Inspection
The respirator user must inspect all components of the
respirator immediately prior to donning the equipment to
verify:
Page 10
•
The service life indicator and shelf-life dates are not
expired;
•
The respirator is clean and sanitized;
•
All component parts are in good condition (i.e., facepiece, helmet, hood, suit, head harness, valves,
connecting tubes, harness assemblies, filters,
cartridges);
•
Connections are tight;
•
The cylinder is undamaged and the pressure gauge
reads “FULL” (SCBA only); and
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© Working in SF6 Atmospheres
SECTION 200: COMPLETING THE CODE OF PRACTICE FORM
•
Regulators, alarms and other warning systems are
functioning properly.
Detailed inspection procedures for SCBA are provided in
Appendix C.
If any damage or malfunction is identified, the respirator
MUST NOT BE USED. Remove from service and tag for
repair by an authorized service centre.
207
Emergency Response Plan
For every employee entering an SF6 atmosphere, the Code
of Practice form must identify a second employee, trained
and equipped, to stand-by in case of emergency. This
employee forms part of the Safety Watch identified on the
Confined Space Code of Practice form.
Constant communication must be maintained between the
employee entering and the standby employee. If any
problem is identified or if communication ceases, the
standby employee must initiate the rescue plan as described
on the Code of Practice form.
November 2003
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Page 11
SECTION 300:
ENTERING AN SF6 ATMOSPHERE
301
A.
Entry Requirement Verification
Code of Practice Review
The Respirator Code of Practice form and, as applicable, the
Confined Space Code of Practice form must be reviewed
prior to entering an SF6 atmosphere to verify that all
requirements have been met.
If changes to either Code of Practice form are required for
any reason, entry is not allowed. The Code of Practice form
must be re-approved by the supervisor.
B.
Air Supply Verification
Every entry into an SF6 atmosphere must be planned to
ensure that there is sufficient air supply to enter, carry out
the tasks required and return to a safe breathing area.
If using SCBA, entry must be made with a fully-charged air
cylinder whenever possible.
If entry or re-entry is attempted after the air has been
partially consumed (the cylinder is less than full), the
respirator user must make certain the remaining air will be
sufficient for safety.
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WORKING IN SF6 ATMOSPHERES
302
A.
B.
Respirator Safety Procedures
Before Entering an SF6 Atmosphere
1.
Conduct a full inspection of all component parts of the
respirator before each use. (See Section 206 and
Appendix C.)
2.
Don the respirator and, if using a tightly fitting facepiece, perform a seal-check. (For detailed SCBA
donning instructions, see Appendix E.)
3.
Open the cylinder valve (or other compressed air supply
valve) fully to start the flow of air and ensure proper
operation of the respirator.
While Working in an SF6 Atmosphere
1.
NEVER remove the face-piece until in a safe area.
2.
If using SCBA, periodically check the remote reading
pressure gauge on the shoulder strap to determine the
rate of air consumption.
WARNING
Don’t expect to obtain the full rated service life from
the cylinder on each use – the service life may be
shorter than indicated, possibly as short as one-half the
rated time. The time remaining after the Vibralert alarm
actuates will be similarly reduced.
The service life of the cylinder is affected by:
Page 14
•
The degree of physical activity of the user;
•
The physical condition of the user;
•
The degree to which the user's breathing is affected
by excitement, fear or other emotional factors;
•
The degree of training or experience which the user
has with this or similar equipment;
•
Whether or not the cylinder is fully charged at the
start of the work period;
November 2003
© Working in SF6 Atmospheres
SECTION 300: ENTERING AN SF6 ATMOSPHERE
•
The possible presence in the compressed air of carbon
dioxide concentrations greater than the 0.04 per cent
normally found in atmospheric air;
•
The atmospheric pressure; for example, if used in a
pressurized tunnel or caisson at 2 atmospheres (15 psi
gauge), the cylinder will last one-half as long as when
used at 1 atmosphere; and at 3 atmospheres it will last just
one-third as long;
•
A loose or improperly fitting face-piece; and
•
The condition of the respirator.
Refer to Table 302-1 for guidelines based on work
intensity.
Table 302-1
Work Intensity
Respired Volume of Air
(litres/minute)
Light work
6 – 15
Moderate work
15 – 25
Heavy work
25 – 40
Very heavy work
40 – 60
Extremely heavy work
60 - 90
Exhaustive work
90 – 120
When the air supply is close to depletion (i.e., there is just
enough air for safe egress), leave the contaminated area and
replace the cylinder according to the procedure described in
Appendix F.
The “Vibralert” alarm will warn you when pressure in the
cylinder has dropped to just 20 - 25 per cent of full capacity
(that is, approximately 75 - 80 per cent of the total air supply
has been used). In areas where more than one respirator is in
use, an alarm in your own unit can be identified by sensing
the vibrations in the face-piece.
A soon as the “Vibralert” activates, leave the area at once
November 2003
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Page 15
WORKING IN SF6 ATMOSPHERES
C.
303
Terminating Respirator Use
1.
When respirator operations are completed and only
when in a safe breathing area, doff the respirator. (For
SCBA doffing procedures, see Appendix G.)
2.
If using SCBA, replace the used cylinder with a fully
charged cylinder. (See Appendix F.)
3.
Check to make sure all components of the respirator are
in good working condition.
4.
Clean the respirator and disinfect the face-piece
assembly. (See Appendix H.)
5.
Document the inspection in the respirator log book.
6.
Store the respirator in accordance with Appendix I and
the manufacturer’s instructions.
Emergency Procedures for Respirator
Malfunction
Follow Manufacturers Specifications.
These emergency procedures are for SCBA malfunction or
suspected malfunction only. They are intended to
supplement, not replace, other emergency response
procedures.
It is imperative to LEAVE THE CONTAMINATED AREA
AT ONCE if these emergency procedures are implemented,
as implementation will increase the rate of consumption of
the air supply and may cause the intensity of the “Vibralert”
alarm to be diminished or stop completely.
A.
Premature Activation of Vibralert Alam
If the “Vibralert” alarm actuates during use before the air
supply is depleted to 25 per cent of full capacity, there may
be a malfunction in the primary breathing circuit causing the
system to automatically transfer to the back-up system.
LEAVE THE CONTAMINATED AREA AT ONCE. When
in a safe area, remove the respirator from service and tag it
for repair by an authorized service centre.
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© Working in SF6 Atmospheres
SECTION 300: ENTERING AN SF6 ATMOSPHERE
B.
Reduced or Cut-Off Air Supply
If the air supply partially or completely cuts off during use
or you are unable to start the flow of air automatically, fully
open the purge valve (red knob on regulator) by turning it
counter-clockwise (pointer on knob downward).
LEAVE THE CONTAMINATED AREA AT ONCE.
Airflow through the respirator when the purge valve is open
can exceed 200 liters per minute. To reduce air depletion,
partially close the purge valve.
When in a safe area, remove the respirator from service and
tag it for repair by an authorized service centre.
C.
Free-Flow of Air
If the air supply begins to flow freely into the face-piece,
fully open the purge valve (red knob on regulator) by
turning it counter-clockwise (pointer on knob downward),
and partially close the cylinder valve by pushing it in and
rotating clockwise to regulate the flow of air.
LEAVE THE CONTAMINATED AREA AT ONCE. When
in a safe area, remove the respirator from service and tag it
for repair by an authorized service centre.
Note: This is the only time the respirator may be operated
with the cylinder valve less than fully open.
D.
Complete Loss of Airflow
If there is sudden and complete loss of air supply, resulting
in total and irreversible loss of respiratory protection,
LEAVE THE CONTAMINATED AREA AT ONCE.
Once in a safe area, remove the respirator from service and
tag it for repair by an authorized service centre.
November 2003
© Working in SF6 Atmospheres
Page 17
SECTION 400:
DOCUMENTATION
401
Record Keeping
Permanent records must be maintained for 10 years for the
following:
• Respirator user training records (SWMS);
• Respirator user health screening reports (occupational
Health Nurse of Doctor);
• Confidential respirator user medical records
(Occupational Health Nurse or Doctor);
•
Respiratory hazard assessments and atmospheric testing
results (job plan and/or the Confined Space Code of
Practice form, as applicable) shall be maintained to
document the initial and ongoing need for respirators;
•
Approved Supplied-Air Respirator/SCBA Code of
Practice forms (MAXIMO® plus hard copy on file,
attached to the Confined Space Code of Practice form,
as applicable); and
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Page 19
WORKING IN SF6 ATMOSPHERES
Non-Permanent Records
• Respirator user fit tests records shall be retained until the
next fit test is administered, (MAXIMO®) or hard copy
on file;
• Respirator inspection, cleaning, maintenance and storage
records shall be retained as required by manufacturer’s
instructions i.e. equipment log book;
Page 20
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© Working in SF6 Atmospheres
APPENDIX A:
Positive Pressure User Seal
Check Using Tight Fitting
Elastomeric Face-pieces
A positive-pressure user seal check can be conducted on respirators
equipped with tight-fitting face-pieces that contain both inhalation
and exhalation valves.
The procedure for conducting the positive-pressure user seal check
shall be as follows:
a.
The user shall don the respirator face-piece, closing off the
exhalation valve or breathing tube or both and exhale gently.
b.
During this period, the face-piece shall not be disturbed by
the user attempting to maintain a seal on the exhaust valve.
c.
If a slight positive pressure can be maintained inside the
face-piece without detection of any outward leakage of air,
the user seal check is successful.
d.
If a slight positive pressure still cannot be maintained inside
the face-piece for 5 seconds, the user shall verify that
nothing obstructs the sealing surface, adjust the face-piece
and harness, and repeat the user seal check.
e.
If a slight positive-pressure still cannot be maintained inside
the face-piece, the user shall remove the respirator, inspect
the components for the cause of the leakage, correct any
problems discovered, or obtain a replacement respirator and
repeat the user seal check.
Qualitative and Quantitative Respirator Fit Tests
Follow manufacturer’s instructions for inspection and
maintenance requirements.
Refer to CAS Z94.4-02 Selection Use and Care of Respirators
Appendix B and Appendix C.
November 2003
© Working in SF6 Atmospheres
Page A-1
APPENDIX B:
Training Requirements for
Respirator Users
Follow manufacturer’s instructions for inspection and
maintenance requirements.
Employees assigned a supplied-air respirator or SCBA must complete
training in each of the following, and know where to access
additional information, i.e. manufacturer’s specifications, training
references.
1.
Respirator fit testing, including instruction and practical
experience in qualitative or quantitative methods (Appendix A);
2.
Identifying respiratory hazards in the workplace, the potential
effects on the worker and means to control the hazards;
3.
Respirator selection process and rationale; and
4.
Respirator care and practical use, including:
•
pre-and post-use checks and problem identification;
•
donning procedure and user seal-checks;
•
respirator service life monitoring;
•
cylinder service life monitoring and replacement, as
applicable;
•
respirator care and maintenance;
•
cleaning and sanitation;
•
change-out of filter elements;
•
inspection;
•
use under failure or emergency modes;
•
storage;
•
removal from service; and
•
familiarity with and adherence to the respirator
manufacturer’s use and care instructions.
Page A-2
November 2003
© Working in SF6 Atmospheres
APPENDIX C:
SCBA Inspection Procedures
Follow manufacturer’s instructions for inspection and
maintenance requirements.
1.
Visually inspect the entire respirator for cleanliness, worn or
aging rubber parts or O-rings, worn or frayed harness webbing or
damaged components.
2.
Check the latest cylinder hydrostatic test date to ensure it is
current: within five years for standard aluminum cylinders and
within three years for composite (fiberglass over-wrapped)
cylinders. Aluminum cylinders are replaced on test failure.
Composite cylinders require a rebuild after 15 years.
3.
Visually inspect the cylinder for dents or gouges in the metal or
the fiberglass wrapping and evidence of exposure to high heat or
flame (i.e., paint turned brown or black, decals charred or
missing, gauge lens melted or damaged elastomeric bumper).
WARNING
Cylinders that exhibit these conditions may suddenly leak or
rupture if charged with compressed air. Empty damaged
cylinders of compressed air then remove from service and tag for
repair by an authorized service centre.
4.
Check the cylinder pressure gauge for "FULL" indication. If the
cylinder pressure gauge reads less than "FULL," replace the used
cylinder with a fully charged cylinder. (See Appendix F.)
WARNING
A cylinder pressure gauge indication other than “FULL” may
indicate an air leak in the cylinder and valve assembly, or a
malfunction of the gauge.
5.
Check to make sure the reducer hose coupling is hand-tightened
to the cylinder valve outlet.
6.
Check to make sure the regulator purge valve (red knob on the
regulator) is closed (turned full clockwise, pointer on the knob
upward).
November 2003
© Working in SF6 Atmospheres
Page A-3
7.
Fully depress, and then release the centre of the donning switch
on the top of the regulator. Slowly open the cylinder valve fully
by rotating the knob counter-clockwise. You should both hear
and feel the “Vibralert” alarm in the face-piece as it starts and
stops. There should be no free flow of air from the face-piece at
this time. (The donning switch is intended to prevent air
depletion when the face-piece is donned and doffed.)
Note: If the donning switch was not depressed fully prior to
opening the cylinder valve, there will be a free flow of air from
the face-piece, and the alarm will not actuate. The respirator is in
“stand-by” condition.
WARNING
If the “Vibralert” alarm fails to actuate or does not stop after a
brief interval, do NOT use the respirator. Remove it from
service and tag for repair by an authorized service centre.
8.
Don the face-piece or hold it tightly to the face to effect a good
seal, and inhale sharply to automatically start the flow of air. If
the flow of air does not start automatically when you inhale,
check to ensure the face-piece is tightly sealed to the face.
9.
Breathe normally from the face-piece to ensure proper operation.
10. Remove the face-piece from the face, and check that air
continues to flow freely from the face-piece.
11. Fully depress, and then release the centre of the donning switch
on the top of the regulator. Check that airflow from the facepiece has stopped.
12. Rotate the purge valve one-half turn counter-clockwise, to full
open position (pointer on knob downward). Check that air is
flowing freely from the regulator.
13. Rotate the purge valves one-half turn clockwise, to full closed
position (pointer on knob upward). Check that airflow from the
regulator has stopped.
Page A-4
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© Working in SF6 Atmospheres
CAUTION
When opening or closing the purge valve, use finger-pressure
only. Rotation of the purge valve is limited to one-half turn.
14. Push in and rotate the cylinder valve knob clockwise to close.
When the cylinder valve is fully closed, open the purge valve
slightly to vent residual air from system. The “Vibralert” alarm
should actuate as the pressure drops below 500 psi. When
airflow stops, return the purge valve to the full closed position
(pointer on the knob upward).
WARNING
DO NOT use the respirator if:
•
the “Vibralert” alarm does not actuate;
•
the purge valve does not operate properly;
•
the donning switch does not perform as described; or
•
any other operational malfunction is noted.
Remove the respirator from service and tag for repair by an
authorized service centre.
November 2003
© Working in SF6 Atmospheres
Page A-5
APPENDIX D:
SCBA Inspection Record
Follow manufacturer’s instructions for inspection and
maintenance requirements.
SCBA INSPECTION RECORD
1.
Inspect the physical condition of the respirator and cylinder:
9
9
9
9
9
9
9
Service life indicator and shelf-life dates are not expired
Respirator is clean and sanitized
All component parts are in good condition (i.e., face-piece,
helmet, hood, suit, head harness, valves, connecting tubes,
harness assemblies, filters, cartridges)
Connections are tight
The cylinder is undamaged (i.e., no dents or gouges, no
evidence of exposure to high heat)
Cylinder pressure gauge reads “FULL”. If not FULL, replace.
Regulators, alarms and other warning systems have been
tested and are functioning properly
2.
If any damage or malfunction is identified, tag the respirator for
repair and ship to an authorized service centre.
3.
Sign and date below, and record the inspection in MAXIMO®.
Inspected by:
Date (DD/MM/YY)
____________________________
_________________
____________________________
_________________
____________________________
_________________
____________________________
_________________
____________________________
_________________
____________________________
_________________
____________________________
_________________
Note: When the card is full, DO NOT DISCARD. Retain
inspection records in the equipment log book.
Page A-6
November 2003
© Working in SF6 Atmospheres
APPENDIX E: SCBA Donning Procedure
Follow manufacturer’s instructions for inspection and
maintenance requirements.
(Equipment: Scott / Safety Supply Canada Ltd.)
Don the harness:
1.
Ensure that the cylinder is firmly locked into position by the
cylinder band toggle lock strap.
2.
Stand to the right (top of the cylinder end) of the open case, lean
forward, position and spread out the shoulder straps, grasp the
back frame with both hands, one on each side of the cylinder. Do
NOT grasp the pressure reducer.
3.
Swing the cylinder apparatus up and over your head, keeping
elbows close to body.
4.
Rest the cylinder apparatus on your back while slightly bent
over. The shoulder straps will slide along your arms and fall into
place on your shoulders.
5.
Straighten up as you pull down on the side straps, to adjust the
harness to fit your body.
6.
Connect the waist belt buckle and adjust further by pulling
forward on the two side-mounted belt ends.
7.
Readjust the shoulder straps to ensure the weight is carried on
the hips.
November 2003
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Page A-7
Don the face-piece:
1.
With neck strap adjusted to the full outward position, hold the
head harness out of the way with one hand, or fold it back over
the viewing area of the lens.
2.
Place the face-piece over the face with the chin properly located
in the chin pocket.
3.
Pull the head harness over the head and tighten the neck straps
by pulling on the two strap ends.
4.
Stroke the head harness down the back of the head using one or
both hands. Retighten neck strap.
Modifications for Cold Weather Use:
A Nose Cup Assembly or Anti-Fog Appliqué must be used:
•
If the respirator will be used at temperatures near or below zero;
•
If the respirator has been stored at temperatures near or below
zero and it is impractical to bring it to room temperature before
use; and/or
•
If the respirator will be used in any other atmospheric condition
that promotes the formation of fog or mist on the interior of the
face-piece lens (i.e., in an atmosphere saturated with water
vapour).
IF USING A NOSE CUP ASSEMBLY, do not exhale into the facepiece until the face-piece is completely donned and the nose cup is
properly in place against the face.
IF USING AN ANTI-FOG APPLIQUÉ, don the face-piece without
the breathing regulator connected. Breathe onto the appliqué surface
inside the face-piece lens while restricting airflow slightly by
partially covering the face-piece inlet opening with one hand.
Continue doing so until the face-piece lens remains clear in the
appliqué area. If clearing does not occur within approximately one
minute, doff the face-piece, place it under your outerwear and warm
it next to your body for approximately two minutes. Re-don the facepiece and repeat the lens clearing process.
Page A-8
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© Working in SF6 Atmospheres
Once the face-piece lens remains clear in the appliqué area, reconnect the breathing regulator.
CAUTION
The effectiveness of an Anti-Fog Appliqué may diminish with
repeated uses or over time. The appliqué or nose cup can be replaced
if it has diminished in effectiveness or sustained damage.
Perform a seal-check:
1. With the face-piece sealed to the face, inhale sharply to actuate
the respirator. Air will be supplied during the inhalation.
2.
Ensure that the purge valve knob is rotated to the full closed
position (pointer on the knob is upward). Fully depress and hold
the center of the donning switch on the top of the regulator.
Inhale slowly and hold your breath momentarily before exhaling.
There must be no air leakage detected and the face-piece must be
drawn slightly to the face.
WARNING
If air leakage is detected or if the flow of air cannot be started
automatically by inhaling, DO NOT USE THE RESPIRATOR.
First, attempt to correct the fit by repeating the donning procedure
and stroking the head harness strongly down the back of the head. If
this is unsuccessful, a different-sized face-piece may be required.
3. Remove your finger from the donning switch and inhale sharply
again. If the respirator is functioning normally, air will be
supplied during the inhalation.
Note: The purge valve should still be closed. If the purge valve is
producing a flow, it may not be possible to reset the donning
switch by inhaling.
November 2003
© Working in SF6 Atmospheres
Page A-9
APPENDIX F: Cylinder Replacement Procedure
Follow manufacturer’s instructions for inspection and
maintenance requirements.
1.
Only when certain that you are in a location where respiratory
protection is not required, doff the face-piece. (Appendix G.)
2.
Push in the cylinder valve and rotate the knob clockwise to close.
3.
Open the purge valve slightly to “bleed down” residual air
pressure. When the flow of air from the face-piece stops, close
the purge valve fully. Remove the cylinder harness to perform
the following steps, or have someone assist you.
•
Unsnap the cylinder band toggle lock strap. Release the
toggle lever by pulling up and then releasing the lock strap.
•
Grasp the cylinder below the band, push the locking tab
below the valve, lift the cylinder free from the bottom hook
and remove.
•
Replace with a fully charged cylinder and valve assembly.
Slide the top of the cylinder upward under the band. Engage
the cylinder hanger in the hook at the bottom of the back
frame.
•
While holding the lock strap, push the toggle lever to secure
the cylinder, and then lock the toggle lever in position by
attaching the cylinder band toggle lock strap to the snap on
the toggle lever.
Note: Do not force the toggle lever. Adjust the band for a snug
fit by sliding the band assembly on the angled side rail.
•
Align the hose coupling with the cylinder valve and tighten.
The respirator is ready for re-use.
Depleted Cylinders
Ensure the cylinder valve is closed when not in use. Before refilling,
the depleted cylinder must be inspected internally and externally by
authorized personnel in accordance with: CSA CAN/CSA B339 and
CAN/CSA B340; the appropriate CGA publications C-6, C-6.1, C6.2; Transport Canada Regulations under Transportation of
Dangerous Goods legislation; and the manufacturers instructions.
Page A-10
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© Working in SF6 Atmospheres
APPENDIX G: SCBA Doffing Procedure
Follow manufacturer’s instructions for inspection and
maintenance requirements.
1.
Loosen the respirator neck strap by simultaneously lifting the
buckle-release levers outward (away from the head) and lifting
the face-piece away from the face.
Note: The buckle-release levers are the U-shaped extensions of
the face-piece buckle assemblies.
2.
To stop air flow from the face-piece, fully depress the donning
switch on top of the regulator and release. If depressing the
donning switch does not stop the airflow from the regulator,
immediately close the cylinder valve to prevent depletion of the
air remaining in the cylinder.
CAUTION
When the donning switch is activated, the purge valve and
“Vibralert” will function normally. If the purge valve has been
adjusted to allow air release or if the “Vibralert” is in operation,
the air supply will continue to be depleted.
An impact to the regulator while the cylinder valve is open and
the donning switch is activated may also cause air flow from the
regulator and depletion of the air supply.
3.
Remove the face-piece by pulling it up and over the head. To
prepare the face-piece for quick re-donning, fold the head
harness over the face-piece lens.
4.
If the respirator is not going to be used for a period of time, close
the cylinder valve.
CAUTION
Leaving the donning switch activated and the cylinder valve
open for an extended period of time may result in intermittent
activation of the “Vibralert,” even when more than 25 per cent of
the air supply remains.
5.
Inspect and clean all components of the respirator and sanitize
the face-piece. (See Appendices D and H)
November 2003
© Working in SF6 Atmospheres
Page A-11
6.
REPLACE THE USED CYLINDER WITH A FULLY
CHARGED CYLINDER.
7.
Record the inspection in the equipment log book and, as
applicable, sign and date the SCBA Inspection Record card. (See
Appendix D)
8.
Store the respirator in accordance with Appendix I.
Page A-12
November 2003
© Working in SF6 Atmospheres
APPENDIX H:
Respirator Cleaning and
Sanitation
Follow manufacturer’s instructions for inspection and
maintenance requirements.
CAUTION
Use only cleaning and disinfecting agents recommended by the
manufacturer or an authorized service centre. Certain cleansers, such
as those containing quaternary ammonium compounds (ammonium
chlorides), and isopropyl alcohol may cause damage, deterioration or
accelerated aging to parts of the respirator.
All respirators must be cleaned after every use:
1.
Remove all filter elements.
2.
Remove the breathing regulator from the face-piece.
3.
Carefully wash the face-piece assembly with a warm (110oF
maximum) soap or detergent solution and THOROUGHLY rinse
in clean water. It is important to remove all detergent residues to
prevent skin irritation on next use.
4.
Sanitize the face-piece by rinsing with a bleach-based solution
(or use an anti-bacterial spray), and allow to completely air-dry.
5.
Re-connect the breathing regulator to the face-piece coupling
and rotate it until it latches in place.
6.
Damp-sponge dirt accumulations from the rest of the respirator,
and replace used filters.
7.
Return the respirator to the carrying case, making sure all
components are thoroughly dry.
November 2003
© Working in SF6 Atmospheres
Page A-13
APPENDIX I:
Respirator Storage
Follow manufacturer’s instructions for inspection and
maintenance requirements.
1.
Respirators must be maintained and stored in a manner that
prevents contamination of the equipment (i.e., cleaned, sanitized
and then stored in the appropriate carrying case).
2.
Respirators must be stored in a readily accessible location, but
not within a confined space where SF6 atmosphere or other
respiratory hazards are likely to exist (e.g., store in the tech
shops; do NOT store in the same room as SF6 circuit breakers).
3.
Respirators should be stored at ambient temperatures above
freezing (0oC).
4.
If a respirator must be stored at a temperature near or below
freezing, special care must be exercised:
•
All components of the respirator must be THOROUGHLY
DRIED after cleaning and before storage;
•
The face-piece and regulator must be PROTECTED
AGAINST EXPOSURE TO WATER.
Page A-14
November 2003
© Working in SF6 Atmospheres