C8 - Electrical Safety Flashcards
1
Q
Extra low, low and high voltage
A
Extra low = < 50v
Low = 50v to 1kv AC or 120 to 1.5kv DC
High voltage = 1KV AC or 1.5KV DC
2
Q
Common causes of electrical fires
A
- Poor, inadequate or damaged insulation
- Overloading of conductors/ appliances
- Over heating flammable materials close to electrical equipment
- Ignition of vapours by electrical equipment
- Mechanical damage
3
Q
Frequency of inspection and testing depends on
A
- Type of equipment and whether it’s hand held
- Manufactures recommendations
- initial integrity and soundness of the equipment
- Age of equipment
- Working environment
- Frequency of use
- Foreseeable abuse of the equipment
- Effects of any modifications
- Analysis of previous records of maintenance and inspection
4
Q
Circumstances permitting live working
A
Where it is unreasonable for the live part to be dead
Reasonable for the person to be at work on or near the live part while live parts
Unpractical to work on it dead such as the need to live test
The need to comply with other statutory requirements
5
Q
Precautions for live working
A
- Trained and competent staff
- Provision of information
- Provision of suitable tools, equipment and protective clothing
- Accompanied working
- Restricted entry to the designated work area.
6
Q
SSoW of installations made dead
A
- Plan job
- Disconnect
- Securely isolate
- Prove test equipment
- Test plant is dead
- Re prove test equipment
- Earth equipment
- Put in place additional precautions if required
- Post notices/ barriers
7
Q
Permits to work should contain
A
- Identity of persons working on the job and supervisor, issued by
- Details of equipment location, and isolation
- Location of isolation points
- Location on temp earth points
- Locations of warning notices and safety locks
- Detailed description of the work to be carried out
- Identification of hazards which might be encountered
- Additional precautions required during the course of the works
8
Q
Competence for an electrical person
A
- Must have adequate knowledge of electricity
- Experienced
- Understanding of the type of systems being worked on
- Understanding of the hazards and precautions required
- Recognise at all times whether it’s safe to continue working
9
Q
Precautions when working near or on underground cables
A
- Cable location plan
- Cable location devices
- Safe digging practices
- Trained personnel
