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WORKING IN SF6 ATMOSPHERES

GUIDE

November 2003 © 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 Page i © Working in SF6 Atmosphere

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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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

November 2003 Page 1 © Working in SF6 Atmospheres

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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104 Additional Resources The following resources were used in developing this guide and may be referenced by employees requiring more information:

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.

105 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.

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 disease-producing 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.


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 Identifying an SF6 Atmosphere A. 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.



Table 201-1: SF6 Byproducts Chemical Formula

Chemical Name Chemical Abstract Service

Registry Number*

Percent by Volume

(laboratory conditions)

HF Hydrogen fluoride 7664-39-3 1.0 SOF2 (SF4) Thionyl sulphide

(sulphur tetrafluoride)

7783-42-8 (7783-60-0)

0.5

SOF4 Sulphur tetrafluoride oxide

13709-54-1 0.085

SiF4 Silicon tetrafluoride 7783-61-1 0.085 S2F10 (SF5) Disulphur

decafluoride 5714-22-7 0.025

SO2F2 Sulphuryl fluoride 2699-79-8 0.006 SO2 Sulphur dioxide 7446-09-5 0.002 CuF2 Copper Flouride AlF3 Aluminum Fluoride WF6, WO3 Tungsten

compounds

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.

http://ccinfoweb.ccohs.ca/

SECTION 200: COMPLETING THE CODE OF PRACTICE FORM


Table 201-2: Exposure Limits – SF6 and Byproducts Chemical Name Permissible Exposure

Limit – Ceiling Permissible Exposure Limit – Time Weighted

Average

Short Term Exposure Limit

Threshold Limit Value

Threshold Limit Value – Ceiling

Sulphur hexafluoride SF6

1 ppm=5.98 mg/m3 1000 ppm

6000 mg/m3 1000 ppm 1250 ppm

7467 mg/m3 1000 ppm

Hydrogen fluoride HF 1 ppm= 2.2mg.m3 @25C@mw 54

3 ppm 3 ppm 6 ppm 3 ppm 3 ppm 2.3 mg/m3

Thionyl sulphide (sulphur tetrafluoride) SOF2 (SF4)

1 ppm

Sulphur tetrafluoride oxide SOF4

0.1 ppm

0.44 mg/m3 0.3 ppm

1.3 mg/m3 0.1 ppm

Silicon tetrafluoride SiF4

1 ppm=2.5 mg/m3 (as Fluorides) 0.1 ppm 0.6 ppm 0.1 ppm

Disulphur decafluoride S2F10 (SF5) 1 ppm=10.39mg/m3

0.01 ppm 0.25 ppm 0.5 ppm 0.01 ppm

Sulphuryl fluoride SO2F2

1 ppm=4.18mg/m3 5 ppm

20 mg/m3 5 ppm

20 mg/m3 10 ppm

42 mg/m3 5 ppm

Sulphur dioxide SO2

1 ppm=5.89mg/m3 2 ppm

5 mg/m3 2 ppm 5 ppm

13 mg/m3 2 ppm 2 ppm

Sulphur tetrafluoride SF4

1 ppm=4.42 mg/m3 0.1 ppm 0.1 ppm 0.1 ppm



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:

• 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.



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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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205 Training A. SF6 Training

Employees who maintain SF6 equipment must:

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.

B. 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:

• 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., face-

piece, 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



• 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.


SECTION 300: ENTERING AN SF6 ATMOSPHERE

301 Entry Requirement Verification A. 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.



302 Respirator Safety Procedures A. 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 face-piece, 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.

B. 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:

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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;



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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



C. 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.

303 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.



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.


SECTION 400: DOCUMENTATION

401 Record Keeping Permanent records must be maintained for 10 years for the following:

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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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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;

November 2003 Page A-1 © 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.

Page A-2 November 2003 © Working in SF6 Atmospheres

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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.


APPENDIX C: SCBA Inspection Procedures


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).


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 face-piece 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.


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.


APPENDIX D: SCBA Inspection Record


SCBA INSPECTION RECORD

1. Inspect the physical condition of the respirator and cylinder:

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.

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.



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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 face-piece 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 face-piece and repeat the lens clearing process.


Once the face-piece lens remains clear in the appliqué area, re-connect 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.


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, C-6.2; Transport Canada Regulations under Transportation of Dangerous Goods legislation; and the manufacturers instructions.


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)


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.


APPENDIX H: Respirator Cleaning and Sanitation


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.


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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.

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