HAZOP and HAZID

What is basic difference between HAZOP and HAZID, Where they are used

some professional feedback

HAZOP deals with process related hazards, HAZID deals with non or other than process related hazards like facility hazards etc. HAZOP focuses on the equipment or pipeline or piece of equipment as node, whereas HAZID takes the facility as a node. HAZOP deals with the internal hazards of the equipment and HAZID deals with the external hazards. While HAZID provides inputs for the COMAH or QRA, HAZOP provides input for the design, operation and maintenance etc. Both techniques use the guidewords to initiate the thoughts making the group hazard identification systematic. Both are complimentary to each other

HAZID ( Hazard Idnetification): (Shell)

HAZID (Hazard Identification) is a technique for early identification of potential hazards and threats. The technique has two styles, Conceptual and Detailed and should be applied at the very outset of a new venture or during the early stages of a development. It is therefore likely to be the first formal HSE-related study for any new project. The major benefit of HAZID is that early identification and assessment of the critical HSE hazards provides essential input to project development decisions. This will lead to safer and more cost-effective design options being adopted with a minimum cost of change penalty.

The HAZID technique is:
• a means of identifying and describing occupational HSE hazards and threats at the earliest practicable stage of a development or venture
• a meeting employing a highly experienced multi-discipline team using a structured brainstorming technique, based on a checklist of potential HSE issues, to assess the applicability of potential hazards
• a rapid identification and description process only, not a forum for trying to solve potential problems.


HAZOP ( Hazard & Operability Study): (ICI)

 Hazard and Operability study is a formal, systematic, critical examination of the process and engineering intentions of the facilities to assess the hazard potential due to mal-operation or mal-function of individual items of equipment and the consequential effects on operation ofthe facility as a whole.
 The method identifies the possible hazards and postulates possible accident scenarios. The safety features provided in the design are then reviewed to determine whether the safeguards are adequate or not. Actions are recommended if deficiency is found in the safeguards provided. The process demonstrates to the owner / management that prudent steps have been taken to make the installation as safe as practicable.
 Hazop is done after the design reviews are completed and the P&IDs are issued. After the Hazop, when all the recommendations are implemented, the P&Ids are approved for construction