FL Water Operator flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Coagulation

Process that neutralizes particle charges and destabilizes suspended solids so they can clump together; rapid mixing disperses the coagulant throughout the raw water.

Flocculation

Gentle, prolonged mixing that encourages destabilized particles to collide and form larger, settleable floc; it follows rapid mix and precedes sedimentation.

Sedimentation basin loading rate

Surface overflow rate equals flow divided by clarifier surface area, usually expressed as gpm/ft²; higher rates reduce settling and may carry floc over.

Detention time formula

Detention time equals tank volume divided by flow rate; use consistent units so volume and flow produce the desired time units.

CT value

CT is disinfectant residual concentration in mg/L multiplied by effective contact time in minutes; it estimates pathogen inactivation and rises with stronger residual or longer contact.

Jar test purpose

Bench-scale test that simulates coagulation, flocculation, and settling to select coagulant dose, pH, and mixing conditions before full-scale adjustment.

Breakpoint chlorination

Point where chlorine demand is satisfied and further chlorine addition produces a rising free chlorine residual; past breakpoint, free chlorine persists for disinfection.

Hazen-Williams head loss

Empirical pipe friction formula relating head loss to flow, pipe diameter, length, and roughness coefficient; smaller diameter or rougher pipe sharply increases head loss.

Water hammer cause

Pressure surge created when water velocity changes suddenly, such as rapid valve closure or pump trip; slow valve operation and surge protection reduce damage.

Cross-connection

Any actual or potential link between potable water and a contamination source; backflow prevention devices or an air gap protect the public water supply.

Air gap backflow prevention

Physical separation between a potable water outlet and the flood level of a receiving vessel; it provides the highest protection against backflow contamination.

Dead-end main problem

Pipe section with no through flow where water stagnates, disinfectant residual decays, and sediment accumulates; looping or routine flushing improves quality.

Thrust block purpose

Concrete or restrained block installed at bends, tees, and caps to resist unbalanced pressure forces that would otherwise separate pipe joints.

Storage tank turnover

Replacing stored water through normal demand and cycling so age does not become excessive; poor turnover can reduce residual and promote stagnation.

Affinity laws

For a centrifugal pump, flow changes with speed, head with speed squared, and power with speed cubed when impeller diameter is unchanged.

Water horsepower formula

Water horsepower equals flow in gpm times total head in feet divided by 3960; brake horsepower equals water horsepower divided by pump efficiency.

NPSH margin

Net positive suction head available must exceed the pump's required NPSH; insufficient margin causes cavitation, vibration, and impeller damage.

Cavitation symptoms

Cavitation produces gravel-like noise, vibration, reduced flow or head, and pitting of the impeller; it occurs when local pressure drops below vapor pressure.

Parallel pump operation

Two pumps discharging into a common header increase total flow, but each operates near its own curve; head rise is usually limited compared with series operation.

Lockout tagout purpose

Procedure that isolates hazardous energy before maintenance so equipment cannot start unexpectedly; each worker applies a personal lock and verifies isolation.

HOCl versus OCl-

Hypochlorous acid is the more effective chlorine disinfectant; it dominates at lower pH, while hypochlorite ion dominates at higher pH.

Turbidity and disinfection

Turbidity particles can shield microorganisms and consume disinfectant; low filtered-water turbidity is required for effective disinfection and treatment performance.

Sodium thiosulfate sampling

Chemical added to bacteriological sample bottles to neutralize chlorine and prevent continued disinfection during transport; it does not sterilize the bottle.

DPD chlorine test

Colorimetric method using DPD reagent to measure free and total chlorine residual; free chlorine reacts immediately, and total includes combined chlorine.

Sample tap flushing

Running the tap before collecting a water sample clears the service line and aerator of stagnant water so the sample represents the main.

Combined chlorine

Chlorine that has reacted with ammonia or nitrogen compounds to form chloramines; it is a weaker disinfectant and can produce taste and odor complaints.

Tier 1 public notice

Immediate notice for serious violations or emergencies with health risk; the water system must notify the public as soon as possible, generally within 24 hours.

Consumer Confidence Report

Annual report that community water systems provide to customers, summarizing source water, detected contaminants, compliance, and health effects information.

Confined space entry

Entry into a space with limited access and possible hazardous atmosphere; requires atmospheric testing, ventilation, an attendant, and a permit before entry.

SDS purpose

Safety Data Sheet provides hazard, handling, first-aid, and spill information for a chemical; it must be accessible to employees under hazard communication rules.

Recordkeeping purpose

Daily logs of flows, residuals, chemical doses, and maintenance create an operating record used for compliance reporting, troubleshooting, and trend analysis.

Chlorine gas leak response

Evacuate, alert responders, and use appropriate respiratory protection; never enter a chlorine release area without training and self-contained breathing apparatus.