# COMAR Title 26 — Department of the Environment

## Subtitle 10 — Oil Pollution Control and Storage Tank Management

### Chapter 18 — Field-Erected Aboveground Storage Tanks

#### Regulation .10 Normal and Emergency Venting.

*COMAR 26.10.18.10*

A. An owner, an operator, and a person in charge of an AST system with a field-erected AST shall ensure the normal venting for the field-erected AST meets the following requirements:

  (1) Design and construct normal venting in accordance with the following industry standards:

    (a) NFPA 30 “Flammable and Combustible Liquids Code”; and

    (b) An API standard applicable to field-erected ASTs incorporated by reference in COMAR 26.10.01.03; and

  (2) Vent an atmospheric pressure AST to prevent the development of vacuum or pressure above a 1.0 psi (6.9 kPa) maximum operating pressure.

B. An owner, an operator, and a person in charge of an AST system with a field-erected AST shall ensure the emergency venting for the field-erected AST meets the following requirements:

  (1) Design and construct emergency venting in accordance with the following industry standards:

    (a) NFPA 30 “Flammable and Combustible Liquids”; and

    (b) API Standard 2000 “Venting Atmospheric and Low-pressure Storage Tanks”; and

  (2) The field-erected AST has one of the following emergency relief venting designs:

    (a) A floating roof;

    (b) A lifter roof;

    (c) A weak roof-to-shell seam; or

    (d) Another industry approved pressure-relieving device.