Technical and operational regulations § 35

§ 35 Depressurisation and flare system

Onshore facilities equipped with or connected to process facilities shall have a depressurisation and flare system. The systems shall prevent escalation of hazard and accident situations by quickly reducing the pressure in the equipment, and shall be designed so that gas releases do not harm personnel or equipment.
It shall be possible to activate the depressurisation manually from the central control room.
Liquid separators installed in the flare system shall be secured against overfilling.
Section last changed: 01 January 2011

The requirement for a depressurisation and flare system as mentioned in the first subsection, entails that non-flammable or hazardous gases shall be directed to a safe emission location, and that any heat load shall be calculated.
To fulfil the requirement for depressurisation and flare systems as mentioned in the first subsection, Chapter 7 of the NS-EN ISO 13702 standard as well as Attachment B.2, and the the API Standard 521 should be used, with the following additions:
  1. fire protection,
  2. when designing depressurisation and flare systems, external environment considerations should be safeguarded by preferably flaring flammable, toxic or corrosive gases.
In addition to manual activation as mentioned in the second subsection, activation signals can also come from relevant safety systems such as the emergency shutdown system.