Warning This information has been archived because it is outdated and no longer relevant.

Archived Content

Information identified as archived on the Web is for reference, research or recordkeeping purposes. It has not been altered or updated after the date of archiving. Web pages that are archived on the Web are not subject to the Government of Canada Web Standards. As per the Communications Policy of the Government of Canada, you can request alternate formats on the "Contact Us" page.

4.3.5.3.(1)
ApplicationIntent
OS1OH5
ObjectiveOS1 Fire Safety
Attribution
[F20,F81-OS1.1]
Application
Application 1: 
Manifolding and sizing of normal vent piping for 2 or more aboveground storage tanks for flammable liquids and combustible liquids, in buildings, structures and open areas.
Exceptions: 
except:
  • as exempted in Sentence 4.3.5.3.(2), which applies to the connection of vent pipes between tanks containing Class I liquids and Class II or IIIA liquids,
  • as exempted in Sentences 4.1.1.1.(2) and (3), which apply to unique hazards at process plants, in transportation, for oil burning equipment, on farms and isolated construction projects, and the storage of aerosol products, and
  • as provided in Sentence 4.10.5.1.(1), which applies to distilled beverage alcohol at distilleries.
Top of Page
Intent
Intent 1: 
To limit the probability that atmospheric temperature changes--or liquids entering or leaving the tank--will lead to excessive internal tank vacuum or pressure, which could lead to the failure of the tank, which could lead to the escape of liquid, which could lead to the ignition of vapour, which could lead to a fire or explosion, which could lead to harm to persons.
Top of Page