2012-054 RES AWARDING CONTRACT FOR REHABILITATION OF EAST ELEVATED STORAGE TANK TO CLASSIC PROTECTIVE COATINGS INC

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SSPC-Guide 6 October 1, 2004 involves the use of more elaborate containment components than Class 1 for power tool cleaning (designated 1 P). For this reason, individual tables have been prepared to identify the containment components for each of the classes according to the type of removal method. When vacuum shrouding is employed around the removal tool, controls equivalent to Class 1 may be achieved through the use of ground covers or free hanging tarpaulins. 4.2.2.1 Class 1: This system provides the highest level of emissions control. For abrasive blast cleaning, Class 1 A normally requires air impenetrable walls, ceiling, and floors, as applicable, with rigid or flexible framing, fully sealed joints, airlock or resealable entryways, and negative air pressure achieved by forced or natural air flow (verified by instrument or visual monitoring) and exhaust air filtration. [NOTE: Class 2 from the original 1992 Guide 61(CON) was combined with Class 1 in 1994 and designated as Class 1 A.] For wet methods of preparation, Class 1 W normally re- quires water impermeable walls, ceiling, and floors with rigid or flexible framing, fully sealed joints, resealable entryways, and negative air achieved by forced or natural air flow (verified visually) and exhaust air filtration. For chemical stripping, Class 1 C normally requires water impermeable and chemical resistant walls, ceiling, and floors, as applicable, and floors with rigid or flexible framing, fully sealed joints and overlapping entryways, and forced or natural air flow with exhaust air filtration.When pressure washing is used to remove the dislodged paint, it may be necessary to specify one of the containments from Table W for the control of the water and waste. For hand or power tool cleaning, Class 1 P normally requires air impenetrable walls with rigid or flexible framing, fully sealed joints, resealable entryways, and negative air achieved through forced or natural air flow (verified visually) and exhaust air filtration. 4.2.2.2 Class 2: This system provides a high level of emissions control. For abrasive blast cleaning, Class 2A normally utilizes air impenetrable walls, ceiling, and floors, as applicable, with rigid or flexible framing, fully sealed joints, partially sealed entryways, negative air pressure achieved by forced or natural air flow (verified visually) and exhaust air filtration. [NOTE: Class 3 in the original 1992 Guide 61(CON) was redesignated as Class 2A in 1994.] For wet methods of preparation, Class 2W normally requires water impermeable walls, ceiling, and floors, as ap- plicable, rigid or flexible framing, fully sealed joints, overlapping entryways, and natural air flow. For chemical stripping, Class 2C normally requires water impermeable and chemical resistant walls, ceiling, and floors, as applicable, and floors with rigid or flexible framing, fully sealed joints, overlapping entryways, and natural air flow. When pressure washing is used to remove the dislodged paint, it may be necessary to specify one of the containments from Table W for the control of the water and waste. For hand or power tool cleaning, Class 2P normally requires air penetrable or impenetrable walls, ceiling, and floors, as ap- plicable, rigid orflexible framing, fully sealed joints, overlapping or open seam entryways, and natural air flow. 4.2.2.3 Class 3: This system provides a moderate level of emissions control. For abrasive blast cleaning, Class 3A normally utilizes air penetrable walls, ceiling, and floors, as applicable, with rigid or flexible framing, partially sealed joints and entryways and exhaust air filtration. [NOTE: Class 4 in the original 1992 Guide 61(CON) was redesignated as Class 3A in 1994.] For wet methods of preparation, Class 3W normally requires water impermeable walls, ceiling and floors, as ap- plicable, minimal framing, partially sealed joints, open seam entryways, and natural air flow. For chemical stripping, Class 3C normally requires water impermeable and chemical resistant walls, ceiling, and floors, as applicable minimal framing, partially sealed joints, open seam entryways and natural air flow. When pressure washing is used to remove the dislodged paint, it may be necessary to specify one of the containments from Table W for the control of the water and waste. For hand or power tool cleaning, Class 3P normally re- quires air penetrable walls, ceiling, and floors, as applicable, minimal framing, partially sealed joints, open seam entryways, and natural air flow. 4.2.2.4 Class 4: This system provides a minimal level of emissions control. For abrasive blast cleaning, Class 4A normally utilizes air penetrable walls ceiling, and floors, as applicable, with flexible framing, open seams and entryways, and natural air flow. For wet methods of preparation, Class 4W utilizes water- penetrable walls, ceiling, and floors, as applicable, with flexible framing and natural air flow to collect dislodged debris while allowing the water to pass though. For chemical stripping, this class is not applicable. For hand or power tool cleaning, this class is not ap- plicable. 4.2.2.5 Containment Class Tables: Tables A, W, C, and P list various containment and ventilation components which can be utilized to achieve these different classes. Table A is used for abrasive blast cleaning, Table W for water blasting/water jetting, Table C for chemical stripping, and Table P for hand or powertool cleaning. The components are described in Sections 5.3 and 6.4. Note that other combinations of containment and ventilation components may provide dust and debris control similar to those suggested in the tables. 4.2.3 OtherConsiderations in Specifying and Selecting Containment Systems: a. Type of structure (simple flat plate or beams versus complex trusses and joists). 9-4