OIT Chemical Handling and Storage 2

Question 1

Alum (aluminum sulfate) is commonly added during water treatment primarily for what purpose?

Accepted Answer

Coagulation and flocculation of suspended particles

Answer

Disinfection of pathogens

Answer

pH adjustment and corrosion control

Answer

Removal of dissolved iron and manganese

Question 2

Polymer chemicals used in water treatment should be stored to avoid which of the following conditions?

Accepted Answer

Freezing temperatures and direct sunlight

Answer

Cool temperatures between 40°F and 60°F

Answer

Humid conditions above 30% relative humidity

Answer

Contact with metal storage racks

Question 3

When a chemical delivery is received at the treatment plant, what should the operator verify FIRST?

Accepted Answer

The chemical matches the purchase order, container labels, and SDS

Answer

The driver's employment records

Answer

Whether the price matches the previous invoice

Answer

The truck's weight before and after delivery

Question 4

Calcium hypochlorite (HTH) stored at a water treatment facility presents which primary hazard?

Accepted Answer

It is an oxidizer that can ignite organic materials and some metals

Answer

It is a strong acid that corrodes metal piping

Answer

It produces hydrogen sulfide gas when exposed to air

Answer

It absorbs moisture and becomes inert over time

Question 5

What does a GHS diamond-shaped pictogram with a flame symbol on a chemical label indicate?

Accepted Answer

The chemical is flammable or an oxidizer

Answer

The chemical is toxic if inhaled

Answer

The chemical causes skin corrosion

Answer

The chemical is environmentally hazardous

Question 6

Which chemical is typically used at water treatment plants to raise the pH of finished water for corrosion control?

Accepted Answer

Sodium hydroxide (NaOH) or lime (Ca(OH)2)

Answer

Sulfuric acid (H2SO4)

Answer

Ferric chloride (FeCl3)

Answer

Potassium permanganate (KMnO4)

Question 7

What is the purpose of a chemical feed day tank at a water treatment plant?

Accepted Answer

To hold a working supply of chemical solution and allow safe, controlled dosing

Answer

To store bulk chemicals at full volume for the entire year

Answer

To mix incompatible chemicals before feeding them to the process

Answer

To dispose of expired or off-spec chemicals safely