Because galvanizing requires no maintenance, the initial cost of a bridge, mass transit station, sign structure,
etc. is the final cost. Therefore, hot-dip galvanized steel is the lowest life-cycle cost corrosion protection system
available, far more economical than painted steel or concrete, which require frequent and costly maintenance
according to a predictable cycle.
The energy input over the life (60-year study)1
of hot-dip galvanized steel is less than half of painted steel.
There is no energy, material, or labor input for maintenance throughout the project lifetime (including
no unnecessary transportation of material and labor to the project site for each maintenance cycle).
The global warming potential (CO2) of hot-dip galvanized steel is one-third, and the acidification
potential (SO2) is less than half of painted steel.1 In another study, the primary energy demand of
hot-dip galvanized steel is less than 50% of that for concrete.2
A third study reported galvanizing
a 550-ton parking garage saves the environment over 63 tons of CO2
emission and the impact
to water (eutrophication) is just 30% of that for a painted garage.3
Hot-dip galvanizing makes steel structures (handrail, guide rail, bridges, signs) safer. The galvanizing process applies
zinc on difficult to reach corners and the inside of poles, box girders, towers, and handrail; places where corrosion
usually begins on painted and unprotected steel. Additionally, galvanized reinforcing steel in concrete bridge
decks corrodes slowly and in such microscopic form it does not cause the spalling of concrete like epoxy coated
and black reinforcing steel can. Zinc is a natural element (27th most abundant in the Earth’s crust), safe,
healthy, and a necessary part of our diet, with a recommended daily allowance (RDA) of 15 mg