Technical Proficiency and Best Practices Flashcards

After a new water main is installed and pressure tested it should be...

Answer: Filled with a solution of 25 ppm to 50 ppm free chlorine for at least 24 hours prior to flushing

After installation and pressure testing, new water mains must be disinfected to eliminate any harmful microorganisms. Filling the main with a chlorine solution at a concentration of 25 to 50 parts per million (ppm) allows for effective disinfection. The recommended duration of at least 24 hours ensures that the chlorine has sufficient time to contact and kill bacteria before the system is flushed and returned to service.

Calculate the volume, in gallons, of a tank that is 75 feet long, 20 feet wide, and 10 feet deep.

Answer: 112,200 gallons

75 ft x 20 ft x 10 ft = 15,000 cu ft 15,000 cu ft x 7.48 gal/cu ft = 112,200 gal

An empty atmospheric storage tank is 8 feet in diameter and 32 feet high. How long will it take to fill 90% of the tank volume if a pump is discharging a constant 24 gallons per minute into the tank?

Answer: 7 hours 31 minutes

8 feet x 8 feet x 32 feet x .785 = 1,607.68 cu ft 1607.68 cu ft x 7.48 gallons per cu ft = 12,025 gallons 12,025 gallons x 0.90 = 10,823 gallons 10,823 gallons / 24 gpm = 451 minutes 451 minutes = 7 hours 31 minutes

What are the two most important safety concerns when entering a confined space?

Answer: Oxygen deficiency and hazardous gases

When entering confined spaces, the most critical safety concerns are the levels of oxygen and the presence of hazardous gases. Oxygen deficiency can lead to asphyxiation, while hazardous gases (such as carbon monoxide, hydrogen sulfide, or methane) can be toxic or explosive. Proper safety protocols, including air monitoring and ventilation, are essential to protect workers in these environments.

Under the requirements of the Safe Drinking Water Act, it is the duty of the water purveyor to deliver potable water of proper quantity only as far as the...

Answer: Consumer's tap inside the home

The Safe Drinking Water Act mandates that water purveyors are responsible for providing safe drinking water up to the point of delivery, which is the consumer's tap. This means that once the water reaches the consumer's premises, the responsibility for maintaining water quality and safety within the plumbing system falls to the homeowner. It emphasizes the importance of ensuring that the water supply is safe and meets regulatory standards at the point of delivery.