Quiz & test questions Grade 11 Careers & CTE
Nettlebourne Cross-Connection Control: A Hazard Survey Quiz
A grade 11 careers quiz on the cross-connection control specialist's work, applying a fictional city ordinance and hazard survey to choose backflow assemblies.
Objectives
- Students will distinguish backpressure from backsiphonage and give an example of each.
- Students will apply a written ordinance and a hazard survey to select the required backflow assembly for a site.
- Students will evaluate an unintended consequence of a citywide backflow prevention ordinance.
Vocabulary
- Cross-connection
- A cross-connection is any place where drinking water pipes are linked to something dirty, like a garden hose left sitting in a bucket of soapy water. If the flow reverses, the dirty water can get sucked in.
- Backflow
- Backflow is water flowing backward through a pipe in the wrong direction, which can pull dirty water into the clean drinking water system. Special devices are installed on pipes to stop it.
Also: backsiphonage, backpressure, containment, isolation, degree of hazard
Teacher overview
This 40-minute quiz is worth 33 points and checks whether students understand the work of a cross-connection control specialist, a utility position that surveys customer plumbing, keeps the assembly records, and enforces testing. The quiz mixes multiple-choice recall with short-answer reasoning, and its middle section asks students to read a fictional ordinance against a fictional hazard survey and decide what each site needs. One misconception is worth correcting before students begin. Many people assume backflow happens only when a water main breaks and pressure in the street drops. Backpressure is at least as common at commercial sites, because a booster pump, a boiler, or a tall standpipe on the customer's side can push water back toward the main with no break anywhere. Items 2 and 7 both turn on that point.
Assessment
Excerpt from the fictional Nettlebourne water ordinance, Section 12
| Rule | What it requires |
|---|---|
| A | Every commercial, industrial, and irrigation service must carry an approved backflow prevention assembly at the service connection. |
| B | A high hazard service, meaning one where backflow could carry a substance that causes illness, requires a reduced pressure principle assembly or an air gap. |
| C | A low hazard service, meaning one where backflow could affect taste, odor, or color but not health, may use a double check valve assembly. |
| D | An irrigation line with no chemical injection and no pump on the customer's side may use a pressure vacuum breaker, which guards against backsiphonage only. |
| E | Any irrigation system that injects fertilizer or pesticide is a high hazard and requires a reduced pressure principle assembly. |
| F | Every assembly is tested at installation, after any repair, and at least once each year, by a tester certified by the state, using a gauge with a current calibration record. |
| G | An assembly that fails its test must be repaired and retested within ten days, or the utility may shut the service off. |
Excerpt from the fictional Nettlebourne hazard survey
| Site | What the survey found | Pressure conditions |
|---|---|---|
| Nettlebourne General Hospital | Dialysis suite, boiler room, laboratory sinks | Main holds about 68 psi; the boiler loop runs higher |
| Quarry Road Office Park | Restrooms, a break room, and lawn irrigation with no injection | Main holds about 68 psi; no pump on the customer's side |
| Coldrey Metal Finishing | Open tanks of plating solution, rinse line fed by a pump | Rinse line runs above main pressure when the pump is on |
| Cedar Field Elementary School | Restrooms, kitchen, and irrigation that injects liquid fertilizer | Main holds about 68 psi; injection pump on the irrigation line |
- (2 points) What does a cross-connection control specialist at a water utility mainly do?
- A) Reads residential meters along a route each month
- B) Surveys customer plumbing for cross-connections, keeps the assembly records, and requires testing or repair
- C) Sets the chlorine dose at the treatment plant
- D) Approves the utility's capital budget
- (3 points) Explain the difference between backsiphonage and backpressure. Give one example of each that could occur at a site in the survey.
- (3 points) Which statement describes containment and isolation correctly?
- A) Containment protects one room, and isolation protects the whole building
- B) Containment protects the public main at the service connection, and isolation protects people inside the building at the fixture or the equipment
- C) They are two names for the same assembly
- D) Containment applies only to single-family houses
- (3 points) Using the ordinance and the survey, name the assembly the hospital needs at its service connection. Cite the rule that requires it.
- (3 points) Name the assembly the ordinance requires at the Quarry Road Office Park service connection, and explain why the survey findings put it in that hazard class.
- (3 points) The office park also has a lawn irrigation line with no injection and no pump. Name the assembly the ordinance allows on that line, and state what it does not protect against.
- (3 points) Coldrey Metal Finishing runs a pump that raises its rinse line above the pressure in the main. Name the assembly the ordinance requires there, and explain what the pump changes about the risk.
- (3 points) An assembly passed its test last year and failed this year, with no change to the plumbing. Give one physical reason that can happen.
- (3 points) The ordinance requires an assembly on every commercial service in the city. Name one unintended consequence of that requirement, and say who bears its cost.
- (3 points) A state inspector asks the specialist to prove that the school's assembly is in
compliance. Which record answers that question?
- A) The customer's most recent water bill
- B) The test report signed by the certified tester, showing the gauge calibration date
- C) The plumbing contractor's business license
- D) The utility's annual water quality report
- (4 points) Name two different routes a person could take into cross-connection control work. State one thing each route would require.
From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.
Answer Key
- Answer: B. The specialist surveys customer plumbing, classifies the hazard, keeps the assembly and test records, and issues notices when a test is due or an assembly fails. Meter reading, plant chemistry, and budgeting belong to other positions.
- Answer: Backsiphonage is backflow caused by a drop in pressure on the utility side, which pulls water backward, as when a main break or heavy fire flow lowers street pressure near the office park. Backpressure is backflow caused by higher pressure on the customer's side pushing water toward the main, as when the hospital boiler loop or the plating shop's rinse pump runs above main pressure. Accept any answer that names the direction of the pressure difference in each case with a matching example.
- Answer: B. Containment is the assembly at the service connection that protects the public main from whatever happens inside the property, and isolation is protection installed at the individual fixture or piece of equipment to protect people inside the building.
- Answer: A reduced pressure principle assembly, or an air gap, under rule B. The survey found dialysis equipment, a boiler loop, and laboratory sinks, which involve substances that could cause illness if drawn or pushed into the main, so the service is a high hazard.
- Answer: A double check valve assembly, under rules A and C. The survey found only restrooms, a break room, and irrigation without injection, so backflow could affect taste, odor, or color rather than health, which is the low hazard class.
- Answer: A pressure vacuum breaker, under rule D. It guards against backsiphonage only, so it would not protect the main if a pump or another source later raised pressure on the customer's side of the line.
- Answer: A reduced pressure principle assembly, under rules A and B. The pump creates a backpressure condition, which means the shop can push rinse water carrying plating solution toward the main without any loss of street pressure, so an assembly that only guards against backsiphonage would not protect the system.
- Answer: Accept any one physical cause. Reasonable answers include debris or scale holding a check valve open, a worn or hardened rubber seat, a weakened spring, a fouled relief valve, or corrosion inside the body of the assembly. An assembly is mechanical, so it wears, which is the reason the ordinance sets an annual test rather than a one-time approval.
- Answer: Accept any reasonable unintended consequence with the party who bears it. Common answers include the cost of purchase, installation, and annual testing falling on small business owners rather than on the utility; a shortage of certified testers making the ten-day repair deadline hard to meet; low hazard sites paying for protection they are unlikely to need; and the utility needing to add staff time to track thousands of test dates. A strong answer names the group that pays, not only the cost.
- Answer: B. The signed test report with a current gauge calibration date is the record that proves a certified tester checked the assembly and that the gauge itself was reliable.
- Answer: Accept any two distinct routes with a matching requirement. Reasonable answers include a plumbing apprenticeship followed by a state backflow tester course and exam; a distribution operator moving into the cross-connection program after completing tester certification; a fire protection or irrigation contractor adding the tester credential to work on assemblies already installed; a code enforcement or building inspection background moving into utility inspection with the tester course added; and a utility customer service position moving into program administration while earning the certification. Each route is a legitimate way into the work.
Differentiation
Support
Give students a one-page assembly guide with a simple drawing of each of the four assemblies named in the fictional ordinance, a one-line description of what it protects against, and the hazard class it matches. Let items 4 through 7 be answered by naming the assembly and the rule letter alone, without the written justification, and allow item 2 to be answered with two labeled arrows on a diagram.
Extension
Have students write the notice the specialist would mail to Coldrey Metal Finishing, stating what the survey found, what the fictional ordinance requires, the deadline, and what happens if the deadline passes. A strong notice quotes the rule, names the assembly, and states the appeal or question contact without threatening language.
ELL supports
Pre-teach "cross-connection," "backflow," "backsiphonage," "backpressure," "containment," and "isolation" using a two-arrow diagram that shows water moving the wrong way for each cause. Provide sentence frames for items 4 through 7: "This site needs a ___ because rule ___ says ___." Allow item 11 to be answered as a list.
Extensions
Have students look up whether their own state certifies backflow assembly testers, and if so what the course and renewal require, then compare that with the operator license the same state issues for treatment or distribution work. Students can also walk their own school building with a custodian or facilities staff member and list three places where a hose, a mop sink, or a boiler makeup line could form a cross-connection, then say which of those would be handled by containment and which by isolation.