With over twenty years of hands on experience working in people’s homes I would say from observation that the circuits most susceptible to parallel arc faults in people’s homes are the lighting circuits.


This is because lighting circuits cables are usually the only circuits in loft spaces and often under insulation in locations where they are extremely prone to vermin damage. It is not at all unusual to find cable insulation stripped by vermin on lighting circuits and you will find far more damage such as this on lighting circuits than any other type of circuits.


So if I were to recommend the installation of AFDD to a circuit, the lighting circuits would be the first I would recommend them for, but the proposed regulation 421.1.7 (vi) says they are circuits AFDD can be omitted from in domestic properties.


Lighting circuits also serve sleeping accommodation, which is where people are generally most vulnerable in their homes.


So the the proposal says that AFDD can be omitted from what I consider to be the most vulnerable circuits that serve the locations where people are most vulnerable, because they are asleep.


Presumably the AFDD can be omitted from domestic lighting circuits because of the high risk of nuisance tripping from switching causing series arc, so the omission is allowable due to lack of reliability of AFDD rather that lighting circuits being low risk.


As an example, a couple of years ago I prepared an EICR for a customer at the request of his insurance company with his home being a straw thatched cottage, I had to replace sections of lighting circuit cables in the loft due to vermin damage. These were the only vermin damaged cables in the house that I could find, yet they would be the only circuits in that house that AFDD could possibly be omitted from. Being a thatched cottage increases the risk, but vermin damage in lofts is not unique to such properties and is common in homes of all types of construction within loft spaces.


The whole proposal to make AFDD compulsory seems inappropriate, but to then say they are not required on domestic lighting circuits appears to be stupid, other than it being because the devices will not perform reliably on these circuits.


Andy Betteridge

With over twenty years of hands on experience working in people’s homes I would say from observation that the circuits most susceptible to parallel arc faults in people’s homes are the lighting circuits.


This is because lighting circuits cables are usually the only circuits in loft spaces and often under insulation in locations where they are extremely prone to vermin damage. It is not at all unusual to find cable insulation stripped by vermin on lighting circuits and you will find far more damage such as this on lighting circuits than any other type of circuits.


So if I were to recommend the installation of AFDD to a circuit, the lighting circuits would be the first I would recommend them for, but the proposed regulation 421.1.7 (vi) says they are circuits AFDD can be omitted from in domestic properties.


Lighting circuits also serve sleeping accommodation, which is where people are generally most vulnerable in their homes.


So the the proposal says that AFDD can be omitted from what I consider to be the most vulnerable circuits that serve the locations where people are most vulnerable, because they are asleep.


Presumably the AFDD can be omitted from domestic lighting circuits because of the high risk of nuisance tripping from switching causing series arc, so the omission is allowable due to lack of reliability of AFDD rather that lighting circuits being low risk.


As an example, a couple of years ago I prepared an EICR for a customer at the request of his insurance company with his home being a straw thatched cottage, I had to replace sections of lighting circuit cables in the loft due to vermin damage. These were the only vermin damaged cables in the house that I could find, yet they would be the only circuits in that house that AFDD could possibly be omitted from. Being a thatched cottage increases the risk, but vermin damage in lofts is not unique to such properties and is common in homes of all types of construction within loft spaces.


The whole proposal to make AFDD compulsory seems inappropriate, but to then say they are not required on domestic lighting circuits appears to be stupid, other than it being because the devices will not perform reliably on these circuits.


Andy Betteridge