Question 4 TK01 - Tank Vessel Assistant - Dangerous Liquids

The Correct Answer is B. ### Explanation for Option B (Correct) **B) start to load slowly:** When loading petroleum products (especially liquids with low conductivity, like gasoline or jet fuel) into a tank, the rapid movement and splashing of the liquid cause significant friction and turbulence. This agitation generates and separates electrical charges, leading to the rapid accumulation of static electricity. By starting the loading process slowly, particularly until the fill pipe is submerged (which typically occurs after the first foot or so of liquid is introduced), turbulence and splashing are minimized. This reduction in agitation directly slows the rate of charge generation, allowing the generated charge to dissipate more safely through grounding and bonding systems, thereby preventing the buildup of dangerously high static potential that could lead to a spark discharge. ### Explanation of Incorrect Options **A) start to load at maximum pressure:** Loading at maximum pressure (high flow rate) from the start drastically increases the turbulence, splashing, and friction as the liquid enters the tank. This maximizes the generation of static electricity, which is the opposite of the desired safety outcome. **C) increase the air flow into the tank:** Increasing airflow (using ventilation) is generally done to reduce flammable vapor concentrations, which is important for overall safety. However, increasing airflow does not reduce the generation or accumulation of static electricity caused by the liquid flow itself. In fact, if the air is dusty or contains mist, the increased movement could potentially contribute to static generation, though the primary source remains the liquid handling. It does not address the fundamental issue of liquid turbulence. **D) use the overall method of loading only:** This option is vague, but assuming "overall method" refers to standard loading practices without specific static control measures (like reduced initial flow), it would inherently risk high static buildup if high flow rates are used immediately. Furthermore, there is no single "overall method" that guarantees static reduction without incorporating techniques like slow initial filling or using anti-static additives. Static control requires specific procedural steps, not just following a general method.