It's about four-fifths as big as a Hot Tub.
In other words, 622 quarts is 0.819 times the size of a Hot Tub, and the size of a Hot Tub is 1.22 times that amount.(for Lifesmart Rock Solid Simplicity Plug and Play 4 Person Spa With 12 Jets) (a.k.a. Spa, a.k.a. Jacuzzi, a.k.a. Whirlpool) (Advertised Capacity)
It's about three-and-a-half times as big as a Bathtub.
In other words, the size of a Bathtub is 0.27 times 622 quarts.(a.k.a. bath, a.k.a. tub) (for Bootz Industries Aloha 5 ft. Left Hand Drain Soaking Tub)
The capacity of a typical bathtub is 170 quarts. Historically, bathtubs have been made of various materials including marble, terracotta, silver, gold, and iron but the size and shape of the tubs has changed little in their 7,000 year history.
It's about eight times as big as a Car Gas Tank.
In other words, 622 quarts is 7.78 times the size of a Car Gas Tank, and the size of a Car Gas Tank is 0.129 times that amount.(for 2009 Ford Taurus)
It's about ten times as big as a Beer Keg.
In other words, the size of a Beer Keg is 0.1 times 622 quarts.(Half barrel; maximum capacity)
It's about one-twentieth as big as a Concrete Mixer Truck.
In other words, the size of a Concrete Mixer Truck is 19 times 622 quarts.(a.k.a. cement mixer, a.k.a. cement mixer truck, a.k.a. cement transport truck, a.k.a. concrete mixer, a.k.a. concrete transport truck, a.k.a. in-transit mixer)(standard size; drum capacity)
It's about 55 times as big as a Basketball (packed).
In other words, 622 quarts is 53.028249998 times the size of a Basketball (packed), and the size of a Basketball (packed) is 0.018857872927 times that amount.(64% packing density) (NBA official ball standards, Size 7)
A NBA official ball, manufactured by Spalding, is a Size 7 ball measures about 7.5069420545 quarts. These balls have 4,118 pebbles each with a diameter of 2.5 mm
It's about 70 times as big as a Bowling Ball (packed).
In other words, 622 quarts is 71.493564053 times the size of a Bowling Ball (packed), and the size of a Bowling Ball (packed) is 0.013987273026 times that amount.(64% packing density) (USBC specifications; tenpin)
According to United States Bowling Congress specifications, a tenpin bowling ball should measure at least 10.795 cm (4.25 in) in radius for a total volume of about 5.5680536461 quarts. Because regulation balls measure the same diameter irrespective of their weight, ball density varies by size and balls weighing less than about 5 kg (11 lbs) will float in water.