Electrical Switchgear Risk Assessment Study and Hazard Analysis Service

Carelabs is licensed provider of electrical Installation’s Study, Analysis, Inspection, and Certification services in UAE and offer electrical switchgear risk assessment and hazard analysis services.

In an electric power system, switchgear is the combination of electrical disconnect switches, fuses or circuit breakers used to control, protect and isolate electrical equipment. Switchgears are used both to de-energize equipment to allow work to be done and to clear faults downstream. This type of equipment is directly linked to the reliability of the electricity supply

One of the basic functions of switchgear is protection, which is interruption of short-circuit and overload fault currents while maintaining service to unaffected circuits. Switchgear also provides isolation of circuits from power supplies. Switchgear is also used to enhance system availability by allowing more than one source to feed a load.

Switchgear can be classified on the basis of voltage level in to the following

1. Low voltage (LV) Switchgear
2. Medium voltage (MV) Switchgear
3. High voltage (HV) Switchgear

Risk assessment is the determination of quantitative or qualitative estimate of risk related to a well-defined situation and hazard.

If you use switchgear you must assess the risks and manage them to ensure safe operation and minimise the risk of injury. A risk assessment is about identifying and taking sensible and proportionate measures to control the risks in your workplace

Principles of Risk AssessmentSafety-related risk assessment includes a series of steps

• Detecting the Limits and scope of use of the switchgear assembly; – design and type of switchgear and rated values – ambient conditions – Intended work procedures, besides the regular switching operations, e.g. maintenance, cable testing, work on LV control equipment
• The next step entails the examination of the associated hazards, for example those due to – electric shock – arc faults – electromagnetic fields – stored charges (electrical / mechanical) – mechanical hazards. The examination of hazards must also take into account the history of service experience, i.e. knowledge about possible minor and major failures on the equipment
• The subsequent risk estimation considers the severity of harms and their probability of occurrence; such as the – level and extend of damage caused e.g. by arc faults – switching rate and probability of a failure on switching operation.
• Finally an evaluation is carried out to determine whether a tolerable risk has been achieved or a risk reduction through further measures is required. This can be done by using a risk graph. It is dependent on the specific industry, which risk class is tolerated in this area.
• Risk reduction implies priorities. Whenever possible the design itself should be inherently safe, supplemented by protective devices and information for the user.

Electrical Switchgear Hazard Categories

The hazards are divided into several main categories, where each category is further subdivided describing specific sources of hazards. The complete list facilitates a thorough check whether all aspects of safety are covered.

The main categories are:

• HC 1 Essential health and safety requirements
• HC 2 Design and construction
• HC 3 Information requirements
• HC 4 Control systems
• HC 5 Guards and protective devices
• HC 6 Installation, operation and maintenance

Inspection of switchgear environment, for example the switchroom or substations, regularly is mandatory. During the inspection you should prioritise any remedial actions as follows:

• Immediate. This should always be the case when security of the substation enclosure has been interfered with.
• Earliest possible opportunity.
• Next scheduled maintenance. You should include the following items in the inspection schedule:
• Switchgear environment (switchroom access and surrounds, including fence and external walls if outdoors):

In Electrical switchgear Safety you should look for following factors

• Signs of water getting in/dampness
• Signs of unauthorised access and/or interference
• Condition of firefighting equipment and warning notices
• General housekeeping
• Signs of abnormal conditions such as high temperature, smell of hot substances or ozone, presence of smoke, signs of fresh leakage of oil or compound, distortion and evidence of sooting on enclosures
• General condition of switchgear, such as corrosion, evidence of leaks, fluid levels, presence/condition of labels, padlocks and key exchange interlocks, condition of instruments and protection equipment
• Condition of ancillary equipment such as batteries and chargers, control panels etc

Accessing The Risks

You should assess the switchgear and the electrical network to identify any potential risks and problems; the system information can help you do this

Risks and problems can include:

• Lack of maintenance
• Overstressing of switchgear
• Presence of.