What is Positive Isolation | Types of positive Isolation.

What is Positive Isolation | Types of positive Isolation.

    What is Positive Isolation?

    Positive isolation means isolation of process (energized) equipment, pipeline & vessels to prevent accidental release of hazardous materials or energy to work area.
    Positive isolation prevent injury, accident or property damage by stopping the flow of hazardous material or energy.

    Working on live or energized process equipment without positive isolation is very dangerous and it is unsafe condition.

    So before starting any work on live equipment make sure live equipment is isolated from work area.

    Purpose of Positive Isolation

    1. For Maintenance
    2. Installing new equipment
    3. For Shutdown Work
    4. For Cleaning

    Types of Positive Isolation

    There are commonly 4 types of positive isolation used for Mechanical job in industries.

    1. Spool removal also called air gaping isolation.

    Spool removal is a method of isolation in which isolation is done by removing a spool section (pipe) from the pipeline, and fixing a blind at the end of process pipeline to stop the flow of hazrardous material  to the work area.

    Spool removal isolation is highly effective method of isolation because in this method energy source physically separated.

    To remove a small spool it is not much difficult but in case of large size spool piece lifting equipment with competent mainpuri required.
    Before removing spool piece LOTO procedure must be followed to prevent accident release of hijras material and authorise operation.

    Read More about LOTO 👈Click Here 


    2. Blind isolation.

    Blind isolation is a method of isolation in which a blind inserted between two flanges.
    Sometime removing spool is not so easy or it may be consume more time, so we follow blind insulation for isolating hazardous material or flow of energy by inserting blind in between two flanges. blind isolation is less safer than spool removal isolation because the energy source is still attached which can flow in case of leak or any defect


    3. Single Valve Isolation.

    In single valve isolation only one valve used to isolate the source of hazardous material or energy. single valve isolation can't be use for long job, it can be used only for changing blind, gas kit or minor job.


    4. Double Block & Bleed Isolation.

    Double block & bleed isolation is considered as most effective snd  safest positive isolation.
    In this method two valves used for isolation, in this isolation method hazardous material bledd (drained) from the bleed valve which is provided between two valve as shown in figure below.
    First close the two valve in series, by closing two series valve hazardous materials will stock in spool (pipe) between two valves now open the bleed valve and drain all material.

    What is Positive Isolation
    Purpose of positive Isolation
    Types of positive Isolation
    Safety mgmt Study 

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