Confined Spaces. 1. Definition Permit/Non-Permit

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1 1. Definition Permit/Non-Permit Confined Spaces A. Non-Permit Required Confined Space: 1. Large enough and so configured that an employee can bodily enter and perform assigned duties. 2. Has a limited or restricted means of entry or exit. 3. Is not designed for continuous employee occupancy. B. Permit Required Confined Space: 1. Presents or has the POTENTIAL for hazards related to atmospheric conditions, engulfment, internal configuration or other recognized serious safety or health hazards. In our work it is usually the potential for unhealthful air that makes the space Permit Required. 2. Classifying Confined Spaces A. Assessment: Prior to entering a confined space, it must first be determined if: 1. The location is a confined space and can be protected while occupied. 2. The confined space is Permit Required. *Note: The scope of work may change the classification from a nonpermitted confined space to a permitted confined space If the operation has potential to contaminate the air. B. Check List: The Permit/Non-Permit Required Confined Space Checklist must be filled out to determine whether the confined space to be entered needs a permit. The permit is valid for one shift only. C. Pre Entry: In order for the checklist to be filled out properly, the air must be tested. The confined space will then be deemed either a permit or non-permit confined space. Page 1 of 10

2 Non-Permit Required Confined Spaces 1. Classification A. Non-Permit Required is: 1. The only Hazard posed by the space is atmospheric (concern for unsafe air). 2. Forced air ventilation is sufficient to maintain safe for entry. 3. The scope of work must not introduce additional atmospheric hazards such as painting. 2. Entry Procedures A. Entry Route: When a confined space may be entered through openings at the top and/ or sides, it is recommended that the entry from the side be used as the primary access. B. Openings: All openings must have their covers removed before entering the space. Conditions making it unsafe to remove an entrance cover shall be made safe before the cover is removed. C. Fall Protection: When removing covers presents a fall hazard, guard rail systems or temporary barriers shall be in place. Workers below must be protected from falling objects. D. Evacuation: Should an unsafe condition develop, all occupants in the confined space must evacuate the space immediately. Alarms on air monitors are set at levels that are not yet immediately dangerous. This allows enough time to exit the area before the gases reach a dangerous level. E. Re-Evaluation: After an evacuation due to any unsafe condition the space shall be reevaluated and all unsafe conditions addressed before re-entry. Spaces may also be re-evaluated if there is reason to believe there has been a change in conditions or at the request of employees involved in the entry. Page 2 of 10

3 3. Testing A. Testing Personnel: Air in the confined space must be tested by a qualified individual with a basic knowledge and understanding of the air testing equipment. Equipment must be calibrated and in good working order according to the manufactures recommendations. B. Testing Frequency: 1. Test prior to the start of work so as to determine the confined space s classification. 2. While workers occupy the confined space, testing shall be done periodically (at least every two (2) hours.) 3. Test before re-entering when entrants have not occupied the space for length of time.( i.e. Retest after breaks and lunch periods or when the space has been left unoccupied for 30minutes or more) C. Testing Procedure: Testing shall be done at 3 levels, Upper, Middle and Bottom. Gases have different weights and may settle at different levels. Approx. 6 UPPER LEVEL Approx. 12 MID LEVEL Approx. 18 LOWER LEVEL 4. Ventilation and Testing A. All non-permit confined spaces shall have sufficient ventilation to assure a continuous flow of fresh air. Page 3 of 10

4 1. Classification Permit Required Confined Spaces PERMITS MUST BE POSTED AT THE ENTRANCE TO THE CONFINED SPACE OCCUPIED BY PERSONNEL A. Permit Required Is: When a hazard makes a confined space immediately dangerous to life or health or has a potential of generating such a hazard. Hazards may include but are not limited to: 1. Engulfment 2. Internal Configuration (Hopper) 3. Atmospheric conditions B. Warning Signs: A sign reading Danger- Permit Required Confined Space shall be posted at all permit confined space on site. 2. Training All employee s involved in confined space work so as to acquire the understanding, knowledge, and skills necessary for the safe performance of their duties. Employee s shall receive training initially, change of responsibility, annual and retraining in the event of a hazardous event. Copies of training records shall be maintained on job and become a part of the permanent records. 3. Duties A. Entrants: 1. Know the hazards that may be faced during entry. 2. Use confined space equipment properly. 3. Communicate with the attendant as necessary. 4. Alert the attendant of warning signs, and recognized hazards. B. Attendants: 1. Know the hazards that may be faced during entry and consequences and behavioral effects. Page 4 of 10

5 2. Continuously maintain an accurate count of entrants in the confined space. 3. Remain outside the space during the operation while communicating and monitoring entrants. Attendants can only monitor a number of spaces he/ she can safely observe and communicate with entrants. 4. Initiate excavation and rescue procedures as necessary. 5. Guard against unauthorized confined space entry. * Attendants cannot have any additional duties* C. Entry Supervisor: 1. Know the hazards that may be faced during entry. 2. Verify that the permit has been completed properly and authorize its use. 3. Terminate entry and cancel the permit when the operation is complete or when a condition that is not allowed under the permit arises. 4. Verify rescue procedures. 5. Remove unauthorized individuals and verify all entrants have exited when work is complete. 6. Coordinate with any other contractors/ employers who may conduct work within the same space and ensure all hazards are communicated. 4. Pre-Entry Procedures A. Initial Testing: Prior to opening or entering a Permit Required Confined Space, the supervisor in charge shall make the initial test of the atmosphere. The atmosphere within the space shall be tested in the following order: 1. Oxygen Level 2. Explosive Gasses Level (LEL) 3. Toxic Gas Level Because some gases are heavier than air and some are lighter, it is possible for the atmosphere inside the space to be stratified, or layered. For this reason, it is important to test the atmosphere at different levels (top, middle and bottom). B. Isolation: 1. Before employees enter a permit required confined space, the space shall be isolated to prevent the entry of hazardous contaminants or contact with other hazards such as energized electrical circuits. 2. The supervisor in charge shall take positive steps to: A. Depressurize the Permit Required Confined Space Page 5 of 10

6 B. Prevent accidental introduction of hazardous materials into the space through interconnecting equipment such as piping, ducts, vents, drains, or other means. C. De-energize and lock-out/tag-out machinery, mixers, agitators or any other equipment containing moving parts in the area. D. Prevent accidental introduction of carbon monoxide gasses from engine driven equipment. C. Ventilation / Purging: The "Permit Required" Confined Space shall be ventilated with either stationary or portable ventilation blowers. They shall be ran prior to entry and at all times during the occupation of the space. COMPRESSED OXYGEN IS NEVER TO BE USED TO VENTILATE OR PURGE ANY CONFINED SPACE. D. Purging Flammable Atmospheres: When flammable contaminants are to be purged, explosion proof ventilation equipment designed for use in hazardous locations and precautions E. Exhausting Contaminated Air The supervisor, or a person designated by the supervisor shall check periodically to ensure that contaminated air from the space is exhausted to a location where it does not present a hazard to employees or equipment. F. Re-Testing: Testing procedures must be repeated until ventilation measures control the hazard. 2. Entry Procedures A. Entry Route: When a confined space may be entered through openings at the top and/or sides of the confined space, it is recommended that the entry from the side be used as the primary access. B. Respiratory Protection: If the atmosphere cannot be brought to a safe entry condition through ventilation, appropriate / approved respiratory protective equipment shall be provided and worn

7 C. Rescue Equipment To facilitate non-entry rescue: 1. A full body harness shall be used whenever an entrant enters a "Permit Required" Confined Space. 2. A retrieval line shall be attached at the center of the entrants back near the shoulder level or above the entrants head. The other end of the line shall be attached to a mechanical device or fixed point outside the "Permit Required" Confined Space. 3. A mechanically assisted device shall be available to retrieve personnel from vertical type "Permit Required" Confined Space more than 5 in depth. Personnel may substitute the mechanical device but must have enough personnel to pull the entrant out. D. Other Required Safety Equipment: Any other appropriate safety equipment shall be provided and worn. The entry permit will state the minimum equipment that is necessary. E. Communication Methods: 1. The authorized entrant and the attendant shall maintain periodic communications with one another through direct line of site, hand signals, and verbal means. 2. If the above communication methods are not practical, alternate communication devices (such as two (2) way radios) may be used. 3. If at any time there is any questionable action or non-movement by the worker inside, a verbal check will be made. If there is no response, the attendant shall order an evacuation of the "Permit Required" Confined Space and follow the emergency procedures set forth in this section. 4. Emergency/Rescue Procedures A. IDLH Entry: Prior to any IDLH entry the project team must consult with the owner representative as to the appropriate procedures for rescue procedures. This can include the use of outside rescue services or on site services. The rescue services team shall be given a tour of the entry site and appropriate time to practice rescue procedures should it be necessary. A site representative shall ensure a clear route is provided for the rescue services to the entry point in the event of an emergency. B. Detection of an Unsafe Condition: In the event that the entrant detects any unsafe condition (gas monitor alarm sounds, entrant feels sick, light headed, etc.), the entrant must inform the attendant that he/she is evacuating the space. The cause of Page 7 of 10

8 the unsafe condition must be identified and evaluated before any subsequent entry. C. The Attendants Response: In case of an emergency, which may arise, the attendant shall be provided the means to contact rescue personnel. Recommended methods may be: 1. Attendant equipped with a two (2) way radio in contact with a person who can immediately call 911and notify appropriate rescue/plant personnel. 2. Attendant may send a standby entrant to call 911 and notify appropriate rescue/plant personnel. This will delay any emergency procedures until the standby entrant returns. D. The Evacuation: If the entrant is unable to evacuate under his/her own power, non-entry rescue procedures shall be used. This means using the safety harness/ lifeline to pull the entrant to safety. E. Disabled Entrant: If the entrant is disabled due to falling or impact, he/she shall not be moved unless a situation becomes immediately dangerous to life or health for that entrant. Steps should be taken to stabilize the injured workers condition. The fire department rescue personnel and an ambulance (911) shall be called to provide rescue and medical services. F. Rescue Personnel: If non-entry rescue is not possible, call designated rescue personnel and an ambulance (911) to provide rescue and medical services. G. Attending the Rescue Process: An attendant (not necessarily the original one) must be stationed outside of the "Permit Required" Confined Space for the duration of the rescue. 5. Program Evaluation: Each Project shall evaluate their Confined Space Program a minimum of annually using cancelled permits. In the event of one of the following the program shall be reviewed at the time of occurrence and revision made to ensure compliance; any unauthorized entry of a permit space, the detection of a permit space hazard not covered by the permit, the detection of a condition prohibited by the permit, the occurrence of an injury or near-miss during entry, a change in the use or configuration of a permit space, and employee complaints about the effectiveness of the program. Page 8 of 10

9 Atmospheric Hazards Oxygen Deficiency The confined space you are about to enter may not contain enough oxygen to sustain life. Here are some facts: Normal air contains 20.9% oxygen Atmosphere containing less than 19.5% oxygen requires the use of appropriate respiratory protection. All confined spaces, which have been closed, should always be suspected of containing insufficient oxygen. Confined spaces should be tested, ventilated, and re-tested to ensure an adequate oxygen level (greater than 19.5% oxygen) before entry. Never enter a confined space containing less than 19.5% oxygen without a Self- Contained Breathing Apparatus (SCBA) or a Supplied Air Respirator (SAR). Too much oxygen presents a hazard as well. An oxygen-enriched atmosphere contains more than 23.5% oxygen and results in a highly flammable environment. The slightest spark could result in the violent burning of clothes or any other combustibles. Explosive Gases The atmosphere in the confined space may be extremely flammable. Carelessness in this situation could result in an explosion. The lowest concentration at which a gas can ignite is called Lower Explosive Limit (LEL). At concentrations lower than the LEL, the gas in the air will not burn. The vapors in the confined space must be less than 10% of the LEL for the entry to occur. If testing reveals the LEL to a greater than 10%, the area must be ventilated until the explosive vapors concentration is below 10% LEL or the entry must be aborted. Page 9 of 10

10 Note: 10% LEL is the minimum concentration of the explosive gases that you must ventilate for your own safety, try to ventilate the confined space to 1% LEL. Toxic Gasses The confined space may contain toxic gases such as hydrogen sulfide (H2S) or carbon monoxide (CO). At high enough concentrations, these toxic vapors can kill or injure you in a single breath. Always test the atmosphere with monitoring equipment before entering a confined space. Smelling is not a reliable means of testing. Some toxic substances are odorless, others are toxic before your nose can detect them, and still others (like H2S), can paralyze your sense of smell before reaching deadly proportions. Some toxic gases are heavier than air and tend to settle at the bottom of the confined space; still others are lighter than air and tend to collect at the top of the confined space. And there are some gases (like CO) that are around the same weight as air and are present throughout the confines space. This can lead to what is known as a stratified atmosphere. In a stratified atmosphere, the atmosphere is layered and the composition of the atmosphere (oxygen, explosive gases and toxic gases) changes throughout the height of the space. Therefore, it is important atmosphere at the top, bottom, and middle levels of the confined atmosphere. A common toxic gas is hydrogen sulfide. Hydrogen sulfide gas is a natural byproduct of decomposing sewage. It has a rotten egg smell and is heavier than air, so it tends to collect at the bottom of spaces. The Occupational Safety and Health Administration (OSHA) has determined the Permissible Exposure Limit (PEL) of H2S to be 10ppm (parts per million). The PEL is the concentration level of a substance to which an individual can be exposed for eight (8) hours a day with no adverse health effects. Carbon Monoxide (CO) is a byproduct of the combustion process, and is present in the exhaust of petroleum driven motors, generators, etc. If CO is a potential hazard in a confined space; the space must be ventilated until the CO level is less than its PEL of 35ppm. Page 10 of 10