Safety Regulations and Procedures GENERAL SAFETY Confined Spaces - S New 11/96. To provide guidance for the safe entry of confined spaces.

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1 CONFINED SPACES PURPOSE REGULATION To provide guidance for the safe entry of confined spaces. Washington Administrative Code - WAC , Part 'M,' Confined Spaces. RESPONSIBILITY Safety Services test & classify Director, Operations & Maintenance training Entry Worker equipment Provide training as requested by the Director, Operations and Maintenance or the Supervisor of Maintenance. Conduct test and evaluation of potential confined spaces and classify accordingly. Based on WAC definitions and requirements, testing, historical information, maintenance experience, and Safety evaluation the following spaces are classified as follows: 1. Crawl spaces - a non-permit confined space; 2. Tunnels - a nonpermit confined space; 3. Manholes/Sprinkler vaults; atmospheric hazard (oxygen deficient); and 4. Boilers - a nonpermit confined space. Inform all potentially exposed employees concerning the potentially hazardous atmosphere (i.e., oxygen deficient) of the manholes/sprinkler vaults. Provide training to supervisors and other employees who may be called upon to enter a manhole/sprinkler vault. The training will include: 1. Viewing a video on Confined Spaces; 2. Review the contents of this regulation and procedure with employees; 3. Supervisor hold a question and answer period concerning items 1 and 2 above; 4. Access to WAC Confined Spaces; 5. Use and care of ventilation equipment and blower to include use and understanding purging times ( S ) and ventilating techniques ( S ); 6. Use of direct reading instruments to test and monitor the atmosphere; 7. Emergency procedures; and 8. Documentation of training and certification of Entry Worker(s). Ensure all equipment used to ventilate the manhole/sprinkler vaults is in proper operating condition. A maintenance and/or calibration log will be maintained for the air blower and gas detection instruments. The gas detection instrument(s) will be clearly marked as to when last calibrated and when calibration is due. Person authorized by the Maintenance Department, and certified through training, to enter the manholes/sprinkler vaults. An Entry Worker is required to following the "alternate procedures" authorized by the WAC and the "acceptable entry conditons" listed in the Manhole/Sprinkler Vault Pre-Entry Check List on page S and S The Entry Worker must review and signature the Pre-Entry Check List (see S and S ) prior to entering a manhole/sprinkler vault. Page 1 of 9

2 DEFINITIONS & BACKGROUND INFORMATION Safety Regulations and Procedures Acceptable Entry Conditions Confined Space Entry Hazardous Atmosphere IDLH Non-Permit Confined Space Oxygen Deficient Permit-Required Confined Space Conditions that must exist in a permit space to allow entry and to ensure that employees involved with a permit-required confined space entry can safely enter into and work within the space. A space that: 1. Is large enough and so configured that an employee can bodily enter and perform assigned work; 2. Has limited or restricted means for entry or exit (e.g., manhole); and 3. Is not designed for continuous employee occupancy. The action by which a person passes through an opening into a hazardous confined space. Entry includes ensuing work activities in that space and is considered to have occurred as soon as any part of the body breaks the plane of an opening into the space. An atmosphere that may expose employees to the risk of death, incapacitation, impairment of ability to self-rescue (i.e., escape unaided), injury, or acute illness from one or more of the following causes: 1. Flammable gas, vapor or mist in excess of 10% of its Lower Explosive Limit (LEL); direct reading gas analyzer is preprogrammed for this level; 2. Airborne combustible dust at a concentration that meets or exceeds its lower flammable/explosive limit; 3. Atmosphere oxygen concentration below 19.5% or above 23.5 %; 4. Atmospheric concentration of any substance for which a dose or a permissible exposure limit is published in chapter WAC, and which could result in employee exposure in excess of its dose or permissible limit; and 5. Any atmospheric condition that is Immediately Dangerous to Life or Health. "Immediately Dangerous to Life or Health" is any condition that poses an immediate or delayed threat to life or that could cause irreversible adverse health effects or that would interfere with an individual's ability to escape unaided (e.g., self rescue) from a permit space. A confined space that does not contain or, with respect to atmospheric hazards, have the potential to contain any hazard capable of causing death or serious physical harm. An atmosphere containing less than 19.5% oxygen by volume. A confined space that has one or more of the following circumstances: 1. Contains or has a potential to contain a hazardous atmosphere; 2. Contains a material that has the potential for engulfing an entrant; 3. Has an internal configuration such that an entrant could be trapped or asphyxiated by inwardly converging walls or by a floor which slopes downward and tapers to a smaller cross-section; or 4. Contains any other recognized serious safety or health hazard. Page 2 of 9

3 Permit Space Program The employer's program for controlling, and, where appropriate, for protecting employees from, permit space hazards and for regulating employee entry into permit spaces. Spokane Public School's primary concern are the manholes/sprinkler vaults which have demonstrated a recurring oxygen deficient atmosphere. Due to the specificity of this atmospheric hazard a Permit Space Program is not required and we are authorized by the WAC to employ "alternate procedures" defined in WAC (5)(b). Alternate Procedures District 81 Procedures Testing work site tests Emergency Procedures authorized by WAC (5)(b) provided that: 1. The employer can demonstrate that the only hazard posed by the permit space is an actual or potential hazardous atmosphere; 2. The employer can demonstrate that continuous forced air ventilation alone is sufficient to maintain that permit space is safe for entry ; 3. The employer develops monitoring and inspection data that supports the demonstrations required by (1) and (2) above. 4. The determinations and supporting data required by (1), (2) and (3) above are documented by the employer and are made available to each employee who enters the permit space. The "alternate procedures" for manholes/sprinkler vaults includes testing, ventilating and monitoring as listed in the Pre-Entry Check List on page S and S The process by which the hazards that may confront entrants of a permit space are identified and evaluated. The employer must specify the tests that are to be performed. The district tested/tests for the following potential gases: oxygen, combustible gases, hydrogen sulfide (sewer gas) and carbon monoxide. Work site tests will include pre-entry and continuous monitoring for an oxygen deficient atmosphere in the manholes/sprinkler vaults by entry workers. A low level of oxygen, less than 19.5%, or any hazardous atmosphere detected requires continuous ventilation of the sprinkler vault or evacuation of the vault. Testing a confined space remotely with a probe extension or lowering an instrument on a strap may be done without bodily entry. Any occurrence, including failure of hazard control or monitoring equipment, or events internal or external to the permit space that could endanger entrants. EMERGENCY CALL The Entry Worker will advise all workers on site what means will be used to notify Emergency Responders. A radio and, or telephone must be identified to serve that purpose. The Entry Worker will ensure access to a telephone will not be impeded due to the lack of a key, combination or other means of access. As needed, advise Emergency Responders (e.g., Spokane Fire Department) about the details concerning the events of the emergency. This may include detection of a hazardous atmosphere, equipment failures, bad source air, and medical or health conditions known about the victim(s) which may have contributed to the emergency. Page 3 of 9

4 Manhole/Sprinkler Vault Pre-Entry Check List Caution: This check list outlines "acceptable entry conditions" and must be filled out and signatured by the Entry Worker(s). This form is valid for only one day or shift. This completed and signatured check list will remain at the work site and be made available to all Entry Workers. Date:. Job Site:. Contract/Work Order #:. Vault # & Location:. SECTION A: GENERAL CHECK LIST. Yes No 1. Is the Entry Workers trained and certified? See S and S Is the Entry Worker(s) trained and ready to evacuate the space if a hazardous atmosphere is detected? 3. Are conditions making it unsafe to remove an entrance cover eliminated before removal? Examples include ice, slippery conditions, fall hazard, water drainage into the vault, loose or depressed foot holds, etc.). 4. Is Physical Barrier Protection (fence, cones, tape, etc) promptly in place when a cover is removed? This is to prevent an accidental fall through the opening and to protect each employee working in the space from foreign objects entering the space? 5. Is the direct reading instrument (i.e., gas analyzer) in calibration? 6. Before worker entry, has the vault atmosphere been tested for the following conditions in the order given or simultaneously with a calibrated direct reading instrument? See page S a. Oxygen content - over 19.5%? If under 19.5% ventilation is required. Alarm = continuous forced ventilation required. 6.b. Oxygen content - under 23.5%? If over 23.5% ventilation is required. Alarm = continuous forced ventilation required. 6.c. Combustible/Flammable gases and vapors (methane)? Alarm = continuous forced ventilation required. 6.d. Toxic air contaminants (e.g., hydrogen sulfide, carbon monoxide)? Alarm = continuous forced ventilation required. 7. Is a direct reading instrument in the vault with the Entry Worker(s) and continuously monitoring the atmosphere for hazardous atmosphere conditons? See caution below. Safety Regulations and Procedures Page 4 of 9

5 SECTION B: ADDITIONAL CHECKS IF CONTINUOUS FORCED VENTILATION IS REQUIRED. Yes No 8. Is the ventilation blower in proper working order and not due for maintenance? 9. Is the air supply for the forced air ventilation from a clean source which will not increase the hazards in the space (near vehicle exhaust, gasoline tank, etc.)? 10. Before entry, is continuous forced air ventilation set up, running and ventilating the space until elimination of any hazardous atmosphere? Use the direct reading instrument to verify this without entering the space. Note: forced air ventilation is not required if no alarms sound unless the intended work may create a hazardous atmosphere (e.g., welding). See ventilation purge times on page S Has the forced air ventilation been used as described on page S and then directed as to ventilate the immediate area where an Entry Worker will be present within the confined space? 12. Is the direct reading instrument in the vault with the Entry Worker(s) and continuously monitoring the atmosphere to ensure the continuous forced air ventilation is preventing the accumulation of a hazardous atmosphere? Note: continuous forced air ventilation is required until all workers have left the confined space? See caution below. CAUTION If a hazardous atmosphere develops the space will be evacuated and remain unoccupied until the space is reevaluated by the Entry Worker(s). Before re-entry it will be determined how the hazardous atmosphere developed. If forced ventilation was not used before the alarm then activate ventilation procedures. If ventilation was being used and the alarm sounded then, after re-evaluation, implement measures to protect entrants from the hazardous atmosphere before re-entry. Entry Workers will be informed of the re-evaluation, conclusions, and protective measures to be implemented. If any Entry Worker has doubt or concerns about proceeding, operations will stop, and the Foreman and, or Maintenance Supervisor will be notified. Signature:. Date:. (Entry Worker) Signature:. Date:. (Entry Worker) Signature:. Date:. (Entry Worker) Page 5 of 9

6 Table of Purging Times Instructions: 1. Place a straight edge on manhole volume (left scale). 2. Place the other end of the straight edge on blower capacity (right scale). 3. Read required purging time (minimum five minutes), in minutes on the diagonal scale. 4. If two blowers are used, add the capacities, and proceed as above. 5. Volume calculations (measurements in feet): a. If shape is rectangle or square; Volume = length x width x height = cubic feet. b. If shape is cylindrical or circular; Volume = 3.14 x (radius x radius) x height = cubic feet. 6. C.F.M. = cubic feet per minute. Safety Regulations and Procedures Page 6 of 9

7 Procedure for Purging and Ventilating Manholes - CAUTION - INITIAL PURGING MUST BE AT LEAST FIVE (5) MINUTES. The purging of manholes must be done completely to remove a hazardous atmospheric condition. Figure 1 illustrates incomplete purging and partial ventilation of a manhole when the supply air hose is directed only downward. Figure 2 illustrates complete purging and ventilation when the supply air hose is directed downward, sideways and into corners or pockets of the manhole. However, even in applying the technique in Figure 2 does not guarantee complete purging and ventilation of the hazardous atmosphere. Once the manhole is entered, again direct the supply air hose toward all corners and pockets to ensure complete purging and ventilation. When purging and ventilation is complete direct the supply air hose toward the area the workers will be positioned to ensure they receive the maximum possible ventilation. - Remember - The Ventilation You Provide Is The Air You Breathe - Your Life Depends On It. Page 7 of 9

8 Hazardous Gas/Atmosphere Test Procedures for Manholes Test Comments - hazards indicated or none Level 1:. Level 2:. Level 3:. Caution If water is present in the manhole do not submerge the test instrument. As needed, use an extension probe with an attached water trap. If an instrument becomes wet ensure that the sensors are completely dry before continued use. Test Procedure Testing must be accomplished at different levels within the manhole due to the possibility of stratification of hazardous gases. Per WAC Part M, tri-level testing will be used for this purpose as depicted in figure 3 above. Test and record instrument readings at each of the three test levels. An indication of a hazardous gas/atmosphere at any level requires purging and ventilation. Page 8 of 9

9 Training Documentation and Certification WAC Part M, Confined Spaces requires that all employees be thoroughly familiar and comply with the requirements for entry and work in a confined space. Documentation and certification of training is to be done using this form. This certificate certifies that Confined Space theory and practical training was provided per WAC Part M, Confined Spaces to the employee listed below. CONFINED SPACES TRAINING Trainee's name:. Training date: Theory date - ; Practical date -. Trainer's name / title:. Trainer 's signature:. Page 9 of 9