Study Guide API 653 Exam
Questions and Answers 100% Pass
API 653 covers which of the following activities?
a) Tank Design
b) Tank Fabrication
c) Tank Operation
d) Tank Reconstrusction - ✔✔d) Tank Reconstruction
Corroded roof plates on a fixed-roof tank shall NOT be less than:
a) Designers Recommendation
b) 0.090" thick averaged over any 100 sqin.
c) 0.500" at any point.
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,d) tmin averaged over critical length "L" Dimension - ✔✔b) 0.90" thick averaged over
any 100sqin.
A new nameplate shall be added to a tank after:
a) either major alterations or tank reconstructions.
b) either major alterations or tank reconstruction.
c) it has been relocated.
d) it has been reconstructed. - ✔✔d) it has been reconstructed.
For a reconstructed tank, the shell thickness readings used to determine the allowable
liquid height must have been taken within the last:
a) 30 days.
b) 60 days.
c) 90 days.
d) 180 days. - ✔✔d) 180 days.
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,The impressed current sources of a cathodic protection system should be checked (to
see if still operating) every:
a) month
b) two months.
c) six months.
d) year. - ✔✔b) two months
Which of the following is part of the "critical zone"?
a) the bottom within 3" of any roof support column
b) the bottom within 3" of the shell
c) the bottom 3" of the lowest shell course
d) the frangible roof to shell weld - ✔✔b) the bottom within 3" of the shell
A tank is 20 years old and has a bottom thickness of 0.170" original bottom thickness
was 0.250. determine the interval for the next internal inspection?
EMILY CHARLENE © 2025, ALL RIGHTS RESERVED 3
, a) 10 years
b) 15 years
c) 17.5 years
d) 20 years - ✔✔c) 17.5 years
Widely catered pits in a tank shell can be ignored if the extent of the pitting does not
exceed:
a)2 pits in any 8 inches.
b) 1 inch in any 8 inches.
c) 2 inches in any 8 inches.
d) 1 inch in any vertical 8 inches.
e) 2 inch in any vertical 8 inches - ✔✔e) 2 inch in any vertical 8 inches.
Which of the following is an advantage of the galvanic cathodic protection system?
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Questions and Answers 100% Pass
API 653 covers which of the following activities?
a) Tank Design
b) Tank Fabrication
c) Tank Operation
d) Tank Reconstrusction - ✔✔d) Tank Reconstruction
Corroded roof plates on a fixed-roof tank shall NOT be less than:
a) Designers Recommendation
b) 0.090" thick averaged over any 100 sqin.
c) 0.500" at any point.
EMILY CHARLENE © 2025, ALL RIGHTS RESERVED 1
,d) tmin averaged over critical length "L" Dimension - ✔✔b) 0.90" thick averaged over
any 100sqin.
A new nameplate shall be added to a tank after:
a) either major alterations or tank reconstructions.
b) either major alterations or tank reconstruction.
c) it has been relocated.
d) it has been reconstructed. - ✔✔d) it has been reconstructed.
For a reconstructed tank, the shell thickness readings used to determine the allowable
liquid height must have been taken within the last:
a) 30 days.
b) 60 days.
c) 90 days.
d) 180 days. - ✔✔d) 180 days.
EMILY CHARLENE © 2025, ALL RIGHTS RESERVED 2
,The impressed current sources of a cathodic protection system should be checked (to
see if still operating) every:
a) month
b) two months.
c) six months.
d) year. - ✔✔b) two months
Which of the following is part of the "critical zone"?
a) the bottom within 3" of any roof support column
b) the bottom within 3" of the shell
c) the bottom 3" of the lowest shell course
d) the frangible roof to shell weld - ✔✔b) the bottom within 3" of the shell
A tank is 20 years old and has a bottom thickness of 0.170" original bottom thickness
was 0.250. determine the interval for the next internal inspection?
EMILY CHARLENE © 2025, ALL RIGHTS RESERVED 3
, a) 10 years
b) 15 years
c) 17.5 years
d) 20 years - ✔✔c) 17.5 years
Widely catered pits in a tank shell can be ignored if the extent of the pitting does not
exceed:
a)2 pits in any 8 inches.
b) 1 inch in any 8 inches.
c) 2 inches in any 8 inches.
d) 1 inch in any vertical 8 inches.
e) 2 inch in any vertical 8 inches - ✔✔e) 2 inch in any vertical 8 inches.
Which of the following is an advantage of the galvanic cathodic protection system?
EMILY CHARLENE © 2025, ALL RIGHTS RESERVED 4
