PAGE 1 OF 7 HEALTH, SAFETY & ENVIRONMENTAL MANUAL PROCEDURE: S400 Scaffolding REV 4.0 8/13/2012

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1 PAGE 1 OF 7 PURPOSE: Scaffolding This procedure details acceptable practices to be used while erecting scaffolding of various types, including tank builder scaffolding and painter scaffolding Procedure: Introduction 1. The supervisor and foreman shall be responsible for providing safe scaffolding. Scaffolding should be solid, rigid, properly secured and capable of carrying the maximum load to which it may be subjected. Any scaffold or scaffold parts, such as planks, brackets, braces, rails that are damaged or weakened from any cause shall be immediately repaired or replaced. Unstable objects, such as buckets, barrels, boxes, shall not be used to support scaffold, nor are they to be used as risers for the employees to stand on. 2. The following procedures are divided by the six types of scaffolding commonly used by the Company. Rolling Two Point Suspension Scaffold Buggy 1. Scaffold buggies should be not less than 20 inches wide and not more than 36 inches wide. They must have steel guardrails, approximately 42 inches, with mid-rails and toe board, four inches high. 2. The buggy must be securely fastened to the roller. If the platform is to be kept at a stationary level or height, it should be fastened to the roller with cable and cable clamps. If the platform must be raised and lowered it may be hung with rope blocks, but the hooks on the rope blocks must have safety pins on them to prevent the hooks from jumping out of the eye they are hooked through. 3. Each person working from a suspension scaffold buggy must be protected by a body harness attached to a lifeline that in turn is attached to the main structure. 4. The scaffold buggy should be suspended by wire cable or by rope capable of supporting at least six times the rated load. 5. The eyes on the roller and on the buggy must be capable of sustaining four times the maximum weight of any load it will carry. 6. All ropes, hangers, platforms and other supporting parts must be inspected before every installation. 7. If possible, scaffold buggies should be lashed to the main structure to prevent them from swaying outward away from the tank shell.

2 PAGE 2 OF 7 8. Extra caution should be used if welding, burning or open flame work is to be performed from any scaffold buggy. Cables and ropes can be burned through very easily. 9. Any employee working on the edge of a tank or tank roof (i.e. an employee who is pushing a buggy or passing tools back and forth from the tank to the buggy) should wear a body harness and lifeline. 10. The work area should be posted with: Danger- Men Working Above signs. Rolling Structural Tower 1. When freestanding structural towers are used the height shall not exceed four times the minimum base dimension (i.e. a tower that is 40 feet tall must have a base that is ten feet wide). 2. Platforms must be made of two inch by twelve inch planks tied securely in place for the full width of the scaffold and extending out past the support angle for one foot on both ends. 3. A ladder or stairway must be provided for safe entrance and exit and must be securely tied, welded or built into the scaffold. 4. Guardrails must be installed on the top section of all structural towers. The rails shall consist of four posts 42 inches high with top-rails, mid-rails and toe boards, four inches tall. Safety Railing 1. Safety railing must be provided around the edge of the tank roof and around openings through which a person could fall when employees are engaged in roof repair that requires the prolonged use of a roof as a work area. 2. Safety railings should consist of posts 42 inches tall, spaced a maximum of eight feet apart, with top-rail and mid-rail consisting of a 3/8 inch cable. Boatswain Chair 1. The chair seat must not be less than ten inches by twenty inches by one inch. The seat must be reinforced on the underside by cleats, securely fastened to prevent the board from splitting. 2. Wire ropes must be used for the seat sling. The sling cable must be at least 3/8 inches in diameter and run through the four seat holes so as to cross each other on the underside of the seat. 3. A safety belt and lifeline must be used. The attachment point of the lifeline to the tank must be changed as the work progresses so that an employee could not fall more than six feet. 4. The tackle for a boatswain chair must consist of at least 5/8 inch diameter, first grade manila rope blocks.

3 PAGE 3 OF 7 5. The overhead anchor must be securely attached to the tank and capable of supporting six times the weight of any load it will carry. 6. All vertical ladders must be constructed of steel with solid welded hooks at the top of the ladder, capable of supporting 800 pounds, and with spacers welded on the lower ends of the side rails to hold the bottom of the ladder away from the tank approximately twelve inches. 7. Ladder rungs must be spaced twelve inches apart and attached to the side rails in a manner to provide rigidity as well as strength. 8. Do not use vertical ladders with damaged or missing rungs or other faults. When such defects are discovered, the ladders must be repaired or tagged out of service and immediately removed from service. 9. Vertical ladders are primarily designed for use on tank rings, but can also be used effectively for access through floating roof manways when the floating roofs are setting on their legs. 10. Always face the ladder when ascending or descending. 11. Avoid carrying heavy tools and equipment up and down the ladder. 12. If a vertical ladder is used on the shell of a tank, with no scaffold or landing beneath it, the employee on a ladder must wear a safety harness and lifeline. 13. The rungs of al ladders should be coated to be skid resistant. Tube and Coupler Scaffolds 1. When platforms are being moved to the next level, the existing platform shall be left undisturbed until the new bearers have been set in place and braced prior to receiving the new platforms. 2. Transverse bracing forming an X across the width of the scaffold shall be installed at the scaffold ends and at least at every third set of posts horizontally (measured from only one end) and every fourth runner vertically. Bracing shall extend diagonally from the inner or outer posts or runners upward to the next outer or inner posts or runners. Building ties shall be installed at the bearer levels between the transverse bracing and shall conform to the requirements of SS <9(1). 3. On straight run scaffolds, longitudinal bracing across the inner and outer rows of posts shall be installed diagonally in both directions, and shall extend from the base of the end posts upward to the top of the scaffold at approximately a 45 degree angle. On scaffolds whose length is greater than their height, such bracing shall be repeated beginning at least at every firth post. On scaffolds whose length is less than their height, such bracing shall be installed from the base of the end posts upward to the opposite end posts, and then in alternating directions until reaching the top of the scaffold. Bracing shall be installed as close as possible to the intersection of the bearer and post or runner and post.

4 PAGE 4 OF 7 4. Where conditions preclude the attachment of bracing to posts, bracing shall be attached to the runners as close to the post as possible. 5. Bearers shall be installed transversely between posts, and when coupled to the posts, shall have the inboard coupler bear directly on the runner coupler. When the bearers are coupled to the runners, the couplers shall be close to the posts as possible. 6. Bearers shall extend beyond the posts and runners, and shall provide full contact with the coupler. 7. Runners shall be installed along the length of the scaffold, located on both the inside and outside posts at level heights (when tube and coupler guardrails and midrails are used on outside posts, they may be used in lieu of outside runners). 8. Runners shall be interlocked on straight runs to form continuous lengths, and shall be coupled to each post. The bottom runners and bearers shall be located as close to the base as possible. 9. Couplers shall be of structural metal, such as dropforged steel, malleable iron, or structural grade aluminum. The use of gray cast iron IS prohibited. 10. Tube and coupler scaffolds over 125 feet in height shall be designed by a registered professional engineer, and shall be constructed and loaded in accordance with such design. (Tank Builder) Shall Scaffold When tank work requires shell scaffolding, the Company s bracket type scaffolding shall be used. 1. Support clips must be secured to the tank shell by welding a bead horizontally across the top portion of the lug. When the weld is completed, the welder must place his initials adjacent to each lug. 2. Scaffold brackets shall be made of 1 ½ inch x 1 ½ inch x 3/16 inch steel angle, with a ¾ inch bar stock pin located at the outer end of the bracket, designed to support the guardrail posts. 3. Scaffold guardrails shall consist of posts made of 1 ½ inch x 1 ½ inch x 3/16 inch steel angel, 42 inches long, and installed in a vertical position of the ¾ inch bar stock pins located at the outer ends of the scaffold brackets. 4. Scaffold top-rails and mid-rails shall consist of 3/8 inch wire rope securely fastened to the posts. 5. Scaffold planks must provide a work platform that is a minimum of 30 inches wide. Planks must be strong scaffold grade lumber, preferably fir, with no splits or knots. The planks must extend over the end of the support bracket, at both ends, not less than twelve inches, which will create an overlapping of the planks by the same minimum twelve inches. 6. The distance between brackets or support lugs shall never be greater than ten feet (i.e., for a large diameter tank, place the lugs and brackets ten feet apart and use three boards that measure 2 inches x 12 inches x 12 feet or 14 feet; for a small diameter tank, place the lugs and brackets six feet apart and use three boards that measure 2 inches x 12 inches x 8 feet or 10 feet).

5 PAGE 5 OF 7 7. If the open space between the innermost edge of the scaffold boards and the curved tank shell exceeds eight inches, a taut wire rope must be strung between the scaffold boards and the tank shell at the same level as the scaffold boards. 8. All loose tools and equipment must be kept in tool containers that are anchored down in such a way as to prevent tipping or spilling tools. This will keep employees from tripping over loose tools or from kicking tools off on someone else. 9. Areas beneath a scaffold on the outside of the tank shell must be roped off and posted with clearly visible signs stating: Danger Men Working Above. These signposts should be located at least 25 feet away from the tank. When scaffold is put on the inside of the shell, a canopy must be placed over all manways so that an employee entering the tank cannot be hit by a falling tool. 10. No more than three employees shall be working on any ten foot span of scaffolding at any one time. 11. An access ladder or equivalent safe access to the scaffold must be provided. This ladder must be tied or secured so that it cannot slip or fall, and it should have rubber non-slip feet on it. 12. Never work off of scaffold boards that are covered with ice. You should either turn the boards over, clip the ice off, or melt the ice with salt. 13. Scaffold boards must be inspected annually and documentation of that inspection maintained on the jobsite. (Tank Builder) Shell Scaffold Erection 1. To begin erection of the tank scaffold, the foreman or assistant foreman needs to determine the starting location of the scaffold and the placement of the scaffold clips. The elevations of the clips will be set 52 inches down from the top of the shell. Once the elevation is set, the scaffold clips will be laid out around the circumference of the tank. The distance between clips will be a maximum of eight feet when twelve foot scaffold boards are being used. 2. Installation of scaffold clips a. The importance of welding scaffold clips on properly cannot be over emphasized. The foreman will select the most qualified welders to perform this work. b. To weld the clip on the plate in position, the welders must be elevated properly so that he/she can see to perform the work, that he/she has something secure to stand on, and if the wind is blowing, see that the work is protected. c. There is only one proper way to weld on these clips. Place on the mark, hold it at a right angles to the shell and tack weld on the left side of the clip when facing it. d. Weld left hand side first. Start across the top of the clip and weld downward the full length of the clip. e. Clean off the slag, inspect and weld second pass across the top and down the right side of the clip for a distance of one inch.

6 PAGE 6 OF 7 f. Clips are welded continuously on the left side because most chippers are right handed. Consequently, chipping or hitting the clip from the right is more easily done then from the left. g. On butt welded tanks, clips should be placed 54 inches down from the top of the plate to the notch in the clip so, if automatic welding is used for horizontal seams, the bottom of the cage will clear the scaffold. h. It is recommended that scaffold clips be used only once. However, in an emergency and upon careful examination where there is no partially cracked off weld metal adhering to the clips, where it presents a uniform surface to weld on, and where the weld can be made the full length of the clip on one side, clips may be used again. i. Prior to hanging the scaffold bracket, the scaffold clip attachment weld shall be inspected and initialed by the foreman or assistant foreman, in accordance with the clip welding procedure. CATUTION: Never weld clips on when chipping or other activities that can cause vibration are taking place in the immediate vicinity. These machines set up vibrations in the plate which can cause hot weld metal to crack and weaken the weld. Any clip not completed prior to a work break will be knocked off the shell before leaving for a break. 3. Place scaffold brackets on the clips, making sure to check that the bracket is all the way down on the clip. 4. Install scaffold boards by starting at the construction ladder and laying three boards between the brackets with a one foot lap over the bracket. 5. Safety posts with cable hand lines are to be installed on top of the scaffold brackets. Check frequently for tangling. Cable is to be installed on the inside of the post. All cable splices require two cable clamps per splice. 6. If there is a twelve inch gap between the scaffold boards and the shell, a cable is to be installed from bracket to bracket for inside fall protection. 7. The construction ladder will be secured to the shell with clips and wedges. For work being performed in the winter, holes should be placed in the bottom of the ladder for water drains (freezing will push them apart). 8. A barricade with Men Working Above signs will be installed below the scaffold to designate the safety zone. 9. The job foreman or his assistant will inspect the scaffold prior to starting work from the scaffold. Raising Scaffold To raise the scaffold from one level to the next, the same steps are to be used with the following additions: % tie off for all employees moving the scaffold.

7 PAGE 7 OF 7 2. The first step is to place three scaffold brackets on the next clips starting at the construction ladder. 3. Place three scaffold boards on the first two brackets. 4. The hand line will be split and angled upward so that it will protect both levels of the scaffolding. 5. The person on the bottom scaffold will hand the scaffold boards to the person on the upper scaffold. 6. The safety post will be handed up and installed next. 7. The person on the upper level can use a bracket puller to pull free the lower bracket and hand to the bottom man. The bottom man will then place the bracket on the next clip. This will continue until the scaffold is up and complete. 8. Upon the completion of the scaffold, the job foreman and/or his assistant will inspect the scaffold prior to the work being performed from the scaffold. Training 1. Employees who erect, dismantle, move or inspect scaffolds shall be trained and qualified to recognize any hazards associated by the work. 2. All employees who perform work on a scaffold shall be trained to recognize hazards associated with the type of scaffold and procedures to control or minimize the hazard. 3. Training shall be given each affected employee initially on employment and retraining performed if an employee demonstrates inadequate knowledge, new equipment or processes developed or when conditions change.