Intent 1:
To limit the probability that:
- the lack of pressure-relief valves will lead to water
pressure in hot water tanks exceeding the tanks' rated working pressure,
or
- the lack of temperature relief valves will lead to an
inability to vent excessively high-temperature water, which could
lead to the formation of steam, which could lead to pressure in hot
water tanks exceeding the tanks' rated working pressure.
This is to limit the probability
of rupture or bursting of storage tanks, which could lead to harm
to persons.