Grounding Requirement for Equipment and Building

Guideline (SOP) for grounding static equipment and building, but it is not applicable to transportation equipment, except when equipment is used in the loading or unloading of flammable material. The requirements of this procedure are minimum requirements & it will be expanding if necessary.

Requirements for Grounding Equipment and Building

1.0   Purpose:

    • The objective of the procedure is to define the minimum requirements for grounding equipment and buildings for the purpose of preventing hazards of electrocution or fire and danger to human life.
    • Ensuring the proper operation of the circuit over protection devices, e.g. fuses, circuit breakers, or relays by providing a ground fault return path.
    • Preventing the accumulation of electric potential.
    • Stabilizing the voltage of the system by a reference point of the earth’s potential.

2.0   Scope:

    • This procedure is applicable to all equipment installed at the pharmaceutical plants for grounding static equipment and building, but it is not applicable to transportation equipment, except when equipment is used in the loading or unloading of flammable material.Grounding of Equipment and Building
    • The requirements of this procedure are minimum requirements & it will be expanded if necessary.
    • If the local legislation is beyond the scope of this procedure, its requirements shall be expanded accordingly.
    • When the requirements or regulations by federal or national authorities differ from those established herein, the most stringent among them will apply.

3.0   References – Grounding of Equipment & Building:

4.0   Responsibilities:

    • User Department shall be responsible for :

    • Ensure that each and every piece of equipment should be earthed and all relevant staff shall be aware of Grounding & Earthing of equipment.
    • If Earthing is not done properly, it shall be corrected with the co-operation of engineering department, to avoid.
    • Maintenance department shall be responsible for:

    • Electrical Engineers and concerned engineering dept. the head shall be responsible for the proper grounding of equipment & buildings.
    • EHS department shall be responsible for:

    • The EHS head and the maintenance head are responsible for the Grounding of equipment and building properly to avoid damages to equipment and danger to human life.
    • Quality Assurance Department:
    • To check the SOP and maintain the master copy of SOP for all departments.
    • Issue controlled copy of SOP & maintain issuance copy record.
    • To retrieve the controlled copy of SOP when it is superseded and to control & Monitor the review process of the SOP.
    • To ensure implementation of SOP
    • IT Department:
    • To provide access authorization for authorized persons as per SOP.

5.0   Abbreviations and Definitions :

    • IT:  Information Technology
    • MCC:  Motor Control Centre
    • NFPA:  National Fire Protection Association
    • Bonding:

    • Bonding is simply the act of joining two electrical conductors together. These may be two wires, a wire, and a pipe, or there may be two pieces of equipment. Bonding has to be done by connecting all the metal parts that are not supposed to be carrying currents during normal operations to bring them to the same electrical potential.
    • Earthing:

    • Meaning of  Earthing is connecting the dead parts (it means the part which does not carry current under normal conditions) to the earth for example -electrical equipment’s frame, enclosures, supports, etc.
    • Earthing Grid:

    • A system of grounding electrodes consisting of interconnected connectors buried in the earth to provide a common ground for electrical devices and metallic structures.
    • Grounding:

    • Grounding means connecting the live parts (it means the part which carries current under normal conditions) to the earth for example neutral the power transformer. It is done for the protection of power system equipment and to provide an effective return path from the machine to the power source.
    • Motor Control Centre (MCC):

    • An assembly of one or more enclosed sections having a common power bus and principally containing motor control units
    • Earth:

    • The conductive mass of the earth where electric potential at any point is conventionally taken as zero.
    • Earth Electrode:

    • A conductor or group of conductors in intimate contact with each other & providing an electrical connection to the earth.
    • Earth Electrode Resistance:

    • The resistance of an earth electrode to earth.
    • Resistance:

    • The opposition that a material offers to the flow of current, expressed in ohms, and which is equal to the voltage ( V, in volts) between two points divided by the current (/, amperes) that flows between those points.
    • Antistatic:

    • Material capable of dissipating a static electric charge at an acceptable rate for the intended purpose. It is also a synonym for conductive or dissipative describing a material that is incapable of retaining a significant electrostatic charge when in contact with the earth. In this context, the word is commonly used to describe a type of foot ware and antistatic additive (ASAs) for use with liquids.
    • Dissipative Footwear:

    • Footwear that ensures that a person standing on a conductive or dissipative floor has a resistance to earth of ˃ 105 ῼ but < 108
    • Conductive Footwear:

    • Footwear ensuring resistance to earth typically < 10 5
    • Dissipative Clothing:

    • Clothing is made from a material with a surface resistivity of < 5 x 10 10 ῼ or with good charge decay characteristics.

6.0   Procedure – Grounding of Equipment and Building:

    • The following below mentioned basic requirements should be ensured by the electrical engineers & their team members.
    • Grounding of equipment/buildings will be installed inside the plant pursuant to the local legislation and standards.
    • Where groundings are concerned, it is recommended to follow the provisions of NFPA 70 and IS 3043 – 1987 Code of practice for Earthing (Indian Standard) concerning all requirements.
    • Further to the requirements of the above-mentioned Standard and Code, this procedure obligates to install additional grounding to each electrical equipment or conductive material which is likely to be charged by electric current.
    • Such type of additional protection will be achieved by installing an additional grounding conductor, an additional electrode, and additional bonding jumpers (if required)
    • The additional grounding conductor will be continuous, of low resistance, and capable of conducting the grounding current that may pass through it. The conductors will be connected to the nearest effective grounding electrode.
    • It is recommended to prefer the connection of the grounding conductor to the main grounding circuit. If not possible, it is required to use an electrode made of a rod, pipe, or metal plate, of max. resistance 25 Ohm, which provides conductivity to the ground.
    • Bonding jumpers will be installed to ensure continuity between conductive elements of equipment, construction, piping, etc. where there is no conduction continuity between them or where resistance to the conduction is too high.
    • The additional grounding conductor does not cancel the need to ground the equipment when required. The additional grounding conductor will not be used for grounding only and is not intended to be used as a low- resistance conductor for returning the current to its source.
    • Additional grounding is required for the following installations/devices/equipment units.

    • Motors operated at a voltage higher than 300V.
    • Motor-operated equipment a voltage is higher than 1000V, such as blowers/fans, compressors, pumps, etc.
    • Generators supply electricity at a voltage higher than 300V.
    • Distribution systems for voltage higher than 300V, such as all transformers, Starters, MCC, etc.
    • Heating devices and their control systems operated at a voltage higher than 300V. Large metal process equipment (not skid-mounted), based on skid-mounted equipment
    • Large metal process equipment (not skid-mounted), based on skid-mounted equipment.
    • Vents of flammable gases.
    • Unburied pipelines of flammable gases and oxygen.
    • Cable trays are made of conductive materials.
    • Control panels connect elements that operate at a current higher than the acceptable local alternating current.
    • Large metal storage tank.
    • Metal fences in which an electric gate is installed operating at a voltage higher than 300V
    • Fences (Metal) installed at a horizontal distance smaller than 7.5m from over headed high voltage lines of a voltage higher than 300V.
    • Metal fences around the electrical system.
    • Permanently installed gas systems.
    • Metal constructions, including buildings, pipeline bridges, and weighbridges.
    • Trucks, trailers, filling/unloading stations where flammable gases, vapors or and liquids, or combustible dust and fibbers are transferred.
    • The grounding effectiveness will be tested periodically.

    • The testing frequency will be according to the local standardization / Legislation, as well as following a significant change in the electrical system (e.g. increase in the connection power, change in protective means, additional circuit or line, completion of an overhaul, and prior to restarting, etc.) Based on the ambient condition and soil resistivity, the frequency of testing shall be defined.
    • In case of the absence of local standardization/legislation concerning the frequency of Periodic inspection of grounding effectiveness, the testing of electric systems of up to 1,000V will be conducted at least once every 1 year, and the grounding test – where electrodes are found in a corrosive environment, at least once in every 6 months.
    • The grounding effectiveness (conductivity) test will be carried out by the authorized examiners who are qualified for this area. The test results will be recorded and these records shall be maintained by the engineering department and a copy shall be maintained by EHS Department. The records shall be maintained until the completion of the next consecutive test of the same grounding system.
    • The identification of every fault in connections, corrosion in conductors or disconnection, requires an immediate inspection of the grounding.
    • Prior to disconnecting a grounding conductor, it is mandatory to install a Bonding jumper instead of it.
    • There shall be a separate Earthing / Grounding Grid for building and Earthing / Grounding of Equipment.
    • Two grounds should not mix anywhere.

7.0   Annexure:

Annexure 1: Grounding / Earthing Information Form


Area / Plant Name of the Equipment / Building Grounding / Earthing Available Resistance in Ohm’s Double Earthing Required & available Date of Checking




Janki Singh is experienced in Pharmaceuticals, author and founder of Pharma Beginners, an ultimate pharmaceutical blogging platform. Email: [email protected]

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