Ladders rungs

Activities associated with bioreactors include gas/hquid contacting, on-hne sensing of concentrations, mixing, heat transfer, foam control, and feed of nutrients or reagents such as those for pH control. The workhorse of the fermentation industry is the conventional batch fermenter shown in Fig. 24-3. Not shown are ladder rungs inside the vessel, antifoam probe, antifoam system, and sensors (pH, dissolved oxygen, temperature, and the like). Note that coils may lie between baffles and the tank wall or connect to the top to minimize openings... 

These vertical cuts are called electron ladders. Rungs are placed on them at the proper E values, and proper species are indicated below and above the rungs. These are shown in Figure 3.3. The exact values of E for the HOH ladder have been calculated from the equations given above, and that for the Mg ladder from E = —2.36 + 0.030 log [Mg+ ], which is the equation that describes the line between Mg+ and Mg on the Mg E-pH diagram. 

A chamber in service for a 10-yr period in which rebuilt valves were present was found to be saturated with chlorides and phosphates. The chloride caused the corrosion of bolts to such an extent that the chamber was leaking. The chamber housed 24-inch and 16-inch valves along with air drain-out. All the bolts on the valves required replacement. Furthermore, the aluminum ladder rungs were completely corroded. 

Figure 7.2 Aluminum ladder rungs. (Reprinted with permission of Dave Raymond, City of Ottawa, Public Works and Services)...

Stage 2A Ladder rungs (-) Non-palpable depression Superficial, white stretch marks... 

Stage 3A Ladder rungs (+) < 1 cm wide Atrophic stretch marks... 

Stage 4 Ladder rungs (++) >1 cm wide Atrophic pearly white stretch marks... 

FUl. 22. Condensation of two ladderlike motifs are shown in Fig. 21 along with the redistribution of the ladder rungs to achieve the tubelike motif found in Sm2fCu... 

Scaffold frames — that are used as access ladders must (1) be specifically designed and constructed for use as ladder rungs, (2) be uniformly spaced within each frame section. 

Step on the top two steps of a stepladder or the top three ladder rungs of an extension ladder. 

A double-cleated ladder, or two or more ladders, must be provided when ladders are the only way to enter or exit a work area having twenty-five or more employees, or when a ladder serves simultaneous two-way traffic. Ladder rungs, cleats, and steps must be parallel, level, and uniformly spaced when the ladder is in position for use. Rungs, cleats, and steps of portable and fixed ladders (except as provided below) must not be spaced less than 10 inches apart, or more than 14 inches apart, along the ladder s side-rails. Rungs, cleats, and steps of step stools must not be less than 8 inches apart, nor more than 12 inches apart, between center lines of the rungs, cleats, and steps. 

Ladder rungs, cleats, and steps shall be parallel, level, and uniformly spaced when the ladder Is In position for use. 

The minimum perpendicular clearance between fixed ladder rungs, cleats, and steps, and any obstruction behind the ladder shall be 7 inches (18 cm), except in the case of an elevator pit ladder for which a minimum perpendicular clearance of 4V2 inches (11 cm) is required. 

When unavoidable obstructions are encountered, the minimum perpendicular clearance between the centerline of fixed ladder rungs, cleats, and steps, and the obstruction on the climbing side of the ladder may be reduced to 24 inches (61 cm), provided that a deflection device is installed to guide employees around the obstruction. 

Furthermore, 1926.1053(a)(2) states Ladder rungs, cleats, and steps shall be. .. level... when the ladder is in position for use. Stepladders are typically designed so that the rungs are level when the ladder is in the open and locked position and the ladder is placed on a stable and level surface. Consequently, it is likely that positioning a stepiadder for use as a non-self-supporling ladder would result in the ladder s rungs being out-of-level, which would violate 1926.1053(a)(2). 

Are nonslip safety feet provided on each metal or rung ladder, and are ladder rungs and steps free of... 

Distance between inside radius of vertical vessels to centerline of ladder rung 1 2 350. 

When a common ladder serves two or more platforms, the ladder rungs must be level with the platforms they serve. The platform elevations must be in even increments to suit the standard 12-in (300-mm) ladder rung spacing. Exhibit 1047 illustrates dris re-... 

Ladder rungs should be equally spaced throughout including the first rung below the landing. 

Ladder rungs should be made of steel, protected from corrosion, and made of nonslip materials. 

Ladder rungs should be used to hold on to when climbing. The use of stringers should be discouraged because there is an increased chance that their hand will... 

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