Re-take - Useful Information for 2394 :

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Re-cap :

For installation(s) with a 230V –single-phase-supply , rated up to 100A ,that are under the control of Ordinary-persons . ( Switchgear & Controlgear )
Comply with , BS-EN-60439-3 & Regulation - 432.1. P/80 .

Be a , Consumer-unit incorporating-components-complying with , BS-EN-60439-3 .

Switch-disconnections, BS- EN-60947-3.

432.1 . Protection against overload-current ( Only) Etc
For a , Circuit-breaker making, anyovercurrent up to & including the ( Maximum-Prospective-Fault-Current ) at the point where the device is Installed.

P/284 : BS-EN-60439-3:1991 . defined as .
Particular-requirementsfor , ( LV ) Switchgear &Controlgear assemblies intended to beinstalled in places where ( Unskilled-persons ) have access totheir use , Distribution-boards .

BS-EN-60439-3:1991+A2:2001

Low-voltage switchgear and controlgear assemblies. Particular requirementsfor low-voltage switchgear and controlgear assemblies intended to be installedin places where unskilled persons have access to their use. Distribution boards

P/150 . 537.1.4. General-requirements.
A main-switch intended for operation by ordinary-persons , of a household orsimilar-installation , should interrupt, both live-conductors of a ,Single-phase-supply .

537.1.4. A main-linked-switch or linked-circuit-breaker shall be provided as near as practicable tothe origin of every-installation as ameans of switching the supply on load & a means of Isolationswitch

P/29 . Isolation :- is the function that Allows operatives to work-safety onelectrical-equipment. BS-7671:2008:2011: as defined as :

A “ function-intended to cut off for reasons of safety the supply from all ,or a discrete-section , of the installation by separating the installation orsection from , every-source of electrical-energy

RCCBs , are devicesdesigned to protect against , fault-currents flowing to earth,

 

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Testing . 2392-10 .
Test-method 1 : use the Line-conductor as a return-lead , Otherwise known as the ( R[SUP]1[/SUP]+ R[SUP]2[/SUP] ) method .
Résistance of the ( CPC )
Q . Why do I need to bother with the, Résistanceof the Line-conductor ?
Reason being : can use Line-conductor as part of the circuit . ( Willyou use a Wander-lead , NO )
Reason : Your ( R[SUP]1[/SUP] + R[SUP]2[/SUP] ) reading can be used for working out your ,Earth-fault-loop-impedance-value . (Circuit-loop-impedance )
Have you , Obtained Polarity . at the same-time . ( L / CPC )
Most used methodused for ring-final-circuit(s) Line-conductor runs alongside a ( CPC ) conductor , factor is utilised in this Test . :yes:

 

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2392-10 . better-understanding.

Test-method 2 : uses the , Wander-lead , it’s title ( R[SUP]2[/SUP] - method)

Your Reason . Wander-lead is a simply a long-length of conductor that can be moved to different-points . in anInstallation .

( R[SUP]2[/SUP] - method) confirm the continuity of , Equipotential-bonding-conductor(s) 612.2.1. :svengo:

2392-10, you do not have a, Line-conductor as a return-path. “ Simple “

 

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For , safety-reasons ... (You may have Implication(s)

( R[SUP]2[/SUP] - method)
Ensure that you have the permission beforehand ( Disconnectany parallel-paths) main-protective-bonding-conductor . Etc

 

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Design-Procedures : of Any- BS-7671: 2392-10 : As , Installers / Designers.

Safety of , Life & Property, are the first-two-important-factors to be considered in the ( Design ) of low-voltage-systems.( LV )

 

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2392-10:- How significant is Insulation-résistance-testing !!

Insulation starts to age as soon as it's made. And, agingdeteriorates its performance.

Installation-résistance-test : Integrityof Conductor(s).

Insulation-résistance, confirmthe reliability of the circuit , in question .

( shorted-connectionwould be obvious from the test-results)

Initial-verification: 2008:2011:
Every-installationshall , during-erection & on-completionbefore being put into service , be . ( Inspected & Tested to verify )

Regulation - 612.3 ( Under-the-section for Initial-verification) :icon_bs:

GN-3 : States :
Insulation-résistance-testedduring various-stages of installation to ( Prove ) the integrity of installed-cables .

 

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2392-10 , thereis always a reason, when I post anyarticle(s) for your benefit . ( can you HIT the Thank-you-button)

 

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( 1MΩ / 2MΩ ) Extracts.

2008: GN-3 , States :

Whole-installation, Periodic-testing... ( Existing )
Single-circuit(s), Initial-Verification... ( New-installation )

Insulation-résistance to Earth.
Single-phase .
Test between the line &neutral-conductor(s) connected together& Earth at the appropriate , distribution-board, of for circuits /equipment not vulnerable to ,insulation-résistance-testing , line & neutral-separately to Earth .
For circuits containing two-way-switching ortwo-way & intermediate-switching ,the switches must be operated one at a time & the circuits subjected to additional-insulation-résistance-test(s)

Where a low-reading is obtained ( Less than 2MΩ ) it may be necessary to test each-conductor-separately to earth , after ensuring that all equipmentis disconnected .

Résistance-readings obtained should be not less than the ,minimum-values , refer , Table – 61

• If a sufficient-high-reading cannot be obtained on the , ( Whole-installation) GN-3 - requires us to . Test ( On any individual circuit(s) discover where any fault is occurring .

Sixth-edition : Inspection& Testing (GN3) provides us with an opportunity comment onthe critical-importance of the Verification-process.
GN3 is, primarily concerned with Part 6 of BS-7671 – Inspection and Testing.
2392-10 , You are only testing , Single-circuits (T&E ) on Initial-Verification. ( You will not Test , Whole-installation)

 

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fifth-edition- 2008 – GN-3 : P/38 , Extracts .
Although an , insulation-résistance-value of not less than ( 1.0MΩ ) complies with the Regulations , where aninsulation-résistance of less than ( 2MΩ ) is recorded the possibility of alatent-defect-exists , in these-circumstances ,
Each-circuit should be tested-separately .
GN-3 , re-cap .
This will help identify (i) whether one-particular-circuit in theinstallation has a lower-insulation-résistance-value , possibly-indicating alatent-defect that should be ( Rectified) Or
(ii) whether the low-insulation-résistance-represents, for example , the summation of individual-circuit-insulation-résistance &as such may not be a cause for concern .

 

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From , 1991 / 2011 . BS-7671 : :icon_bs:

P/29 . Insulation : Suitable non-conductive-material enclosing, surrounding or supporting a conductor .

 

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Useful-junk .
P/29 , Leakage-current : Electric-current in anunwanted-conductive-path , under normal-operating-conditions .
Touchcurrent :- also known, as earth-leakage-current must be withinspecified limits for its Class. :aureola:
Class I equipment, the earth-leakage-current is thecurrent that flows in the earth supply conductor during normal operation of theequipment.
Class II equipment, leakage is measured to earth fromaccessible conductive-parts of the enclosure

 

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2008: GN-3 ,States : if test an installation as a whole
Insulation-résistance to earth.
" Although aninsulation-résistance-value of not lessthan 1.0 MΩ complies with the Regulations, where an insulation resistance ofless than 2MΩ is recorded the possibility of a latent defect exists. ( In these circumstances, each circuit should be tested separately ) "

2392-10
" Although an insulation-résistance-value of not less than (1MΩ complies with the Regulations ), New-installations should not yield test results this low "

( 299MΩ ) . reason(s) , New-installation .

 

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Circuits must be designed that are fit for purpose andsuitable for the load they are intended to supply. They should be correctlydesigned in accordance with BS-7671.

Useful-junk .

New numberingsystem introduced for UK-only national regulations . :icon_bs:

In Amendment - 1 , UK national regulations willend in 100, 101,102, etc.

Regulation , 522.6.7 now 522.6.102

Regulation , 433.1.5 now 433.1.103

This will show-regulations that are specificto the ( UK only and not used in theEU )

 

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Useful-junk

1988 an agreement was reached that , voltage-levels across Europe should be unified at 230V , Single-phase & 400V , Three-phase with effectfrom , January 1[SUP]st[/SUP] 1995 .

Tables in the 17[SUP]th[/SUP] Editionhave been , recalculated to take account of the unified-voltage-levels . 230V & 400V

BS-7671: Made a Stand . :icon_bs:

Introduction of the ( Free-European-Marker in 1993 ) caused serious-problems for , UK electrical-contractors . IEE / IET wiring-regulations were held in high-esteem .they had , no-legal-status thatwould require Europeans who werecarrying out , installation-work in the UK to abide by them .

1992 , when the , IEE / IET wiring-regulation(s) became a (British-Standard ) BS-7671: giving them therequired-international-standing , from 2010 , BS-7671:

 

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Useful-junk: 2011:
Definition :- JPEL/64 . Regulation – GP / 10 . as at June 2011.
The , UK National-Committee-responsible for , BS-7671: is ( JPEL/64 ) :icon_bs:
J ... joint IET / BSI – committee .
P ... Power .
EL ... Electrical .
64 ... IEC– designation for Committees dealingwith , low-voltage-electrical-installations .

 

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BS-7671:2011: have stated the facts for us . :icon_bs:

2394 : RCCBs are still out-there ,
BS-EN-61009-1 ( RCBO ) BS-EN-61008-1 – ( RCCBs )

p/286 . BS-EN-61008-1:2004 + 12:2009
Residual-current-operated-circuit-breaker(s) without, integral-overcurrent-protection for household & similar uses ( RCCBs ) – Part 1 : General-rules
Introduction , Chapter -41 , 411.4.9.
411.4.9. . P/57
Where an , RCD is usedto satisfy the requirements ofRegulation , 411.3.2.2. the maximum-values of , earth-fault-loop-impedance in ,table- 41.5 may be applied for non-delayed RCDs to BS-EN-61008-1. & BS-EN-61009-1 . for anominal-voltage , ( Uo of 230V ) in such-cases , anovercurrent-protective-device shallprovide protection against , overload-current & fault-current in accordancewith Chapter – 43 .

411.3.2.2. Automatic-disconnection in case of a fault .
The maximum-disconnection-time stated in , Table -41.1 shall be applied to final-circuitsnot exceeding 32A .
Table 41.5.
Maximum , earth-fault-loop-impedance( Zs ) for non-delayed RCDs . to BS-EN-61008-1. & BS-EN-61009-1 for ( Uo of 230V ) Regulation – 411.5.3.

Table 53.4. Guidance on the selection of protective , isolation & switching-devices .

710.411.3.2.1. Medical-Locations .
Care shall be taken to ensure that ,simultaneous-use of many-items ofequipment-connected to the same-circuit , cannot-cause unwanted-tripping of the residual-current-protective-device ( RCD )

710.410.3.4. Exhibitions , Shows & Stands .
A cable-intended tosupply-temporary-structures shall beprotected at its origin by an RCD whose-rated-residual-operating-current , dosenot exceed 300mA , This device shallprovide a delay by using a device in accordancewith BS-EN-60947-2 , or be the ( S – type in accordance with BS-EN-61008-1 ) or BS-EN-61009-1for discrimination with RCDs protecting-final-circuits .

Note : The requirement for ,additional-protection relates to theincreased-risk of damage to cables in temporary-locations.

721.411.1 Electrical-Installations in Caravans & Motor-caravans .
Where-protection byautomatic-disconnection of supply is used ( Section – 411 ) an RCD – complying with , BS-EN-61008-1 . & BS-EN-61009-1, interrupting all-live-conductors’ shall be provided having the characteristics specified in Regulation –415.1.1. & the wiring-system shall include a circuit-protective-conductor which shall be connected to . Etc . refer . 721.411.1 (i) (ii) (iii)

740.410.3. Section – 740 .
Automatic-disconnectionof supply to the temporary-electrical-installation shall be provided at theorigin of the installation by one or more RCDs with a rated-residual-operating-current not exceeding 300mA , the RCD shall incorporate, time-delay in accordance with BS-EN-60947-2 , or be the ( S – type inaccordance with BS-EN-61008-1 ) or BS-EN-61009-1 , where necessary to provide discrimination with RCDs protecting-final-circuits .

740.411 , Note .
p/295 . Appx 3, Table – 3A . Time / current , characteristics of overcurrent-protective-devices & RCDs

am justbring it to your Attention . BS-EN-61008-1

 

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What’s in a Book.

Re-cap : GN-3 ,P/11 , offers Us Guidance. 2394 . What will help me in my ,Exams . ( Better-understanding )

Safety:
Electrical-testing inherently-involves some degree of Hazard .

It is the Inspector’s-duty to ensure his ( or her ) ownsafety , & that of others , in the performance of the test-procedures .

The safety-procedures detailed in , Health &Safety-Executive-Guidance , Note GS-38 .( revised )

Electrical-test-equipment for use by , electrician’s should be observed . When testing does not require the equipment orpart of an installation to be ( Live )

It should be made ( Dead) & ( Safety-isolated)

Guidance on ( Live & Dead-working ) Safety-Executive-publication , Memorandum of guidanceon the , Electricity-at-work-Regulations – 1989 ( HSR.25 )

Guidance on, Safe-isolation-procedures can be found in a ,best-practice-guide-published by the , ESC .

 

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What are the Objectives of the IET– Wiring-regulation(s) BS-7671:2008: 2011.

To ensure the ( Protection) of people & livestock from , fire , shock or burns from any installation thatcomplies with their-requirement’s.

 

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What in the Eyes of , The IET-Wiring-Regulations ( Cover) Main-cover , The Words , Wiring-Regulations.

Re-cap , TheRegulations cover both : ( What ?? ) :icon_bs:

Electrical-installation(s).
Electrical-equipment .

 

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It assumes that behind every Electrician thereis a Designer. :icon_bs:

Ohm’s-law , the current-flowing will depend on thevoltage-applied & the résistance of the current-path.

In the Eyes of ,BS-7671:2008:2011:
Limit the severity of , Electric-shock is the limitation of ,Earth-fault-loop-impedance .

As Electrician’s, we know this all too well . Electric-shock results from contact with a conductor that form-part of a circuit . ( Live )

Circuit-breaker(s) :- Overcurrent-protective-system will offer , no-protection
RCDs . RCBOs /MCB . RCD with an opening-current of 30mA . ( BS-7671: do not claim great expectations , Additional-protection ) May-do-so . 2392-10 . Can a RCD become faulty or is faulty . that’s why Testing is very-important .

GN-5 : The effects of an , Electric-shock ... ( Dependent on the current )
Depends on two-factor(s)

• Value of shock-current-flowing .
• Time for whichit flows . ... ( Additional-protection )

Human-body is composed largely of water, & has very-low-résistance ( Theskin has very-high-résistance )

 

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Just making you aware : ( Fixed-electrical-equipment )

Protection from Burns . 423 . P/77 :icon_bs:

Regulations provide a Table showing the , Maximum-allowable-temperatures-surfaces, that could be touched & thus-cause-burns .
From you point of view , Very-Young , Old , Infirm . Etc

Accessible-part of equipment within-arms-reach , refer

 

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Working my way around the Regulations .

Overcurrent-Protection. against Overcurrent . 43 . P/79 :icon_bs:

The term can bedivided into two-types of excess-current .

Overload-current(s) ... ( higherthan those intended to be present in the system )
Short-Circuit-Current(s)... ( These currents will only occurunder , fault-conditions )

-&-s. The type of fault which occurs when a Line-conductor comes in contact with aneutral-conductor is called : ( short-circuit-fault)

430.1. This chapter provides-requirements for theprotection of ( Live-conductors fromthe effects of Overcurrent )

Etc . describes how ( Live-conductors are protected by one-or-more-devices for the automatic-disconnection of the supplyin the event of Overload-current )

Note - 1, Live-conductors-protected against-overload in accordance with Section – 433 are also considered to be protection-against-faults, likely to cause overcurrents of a magnitude similar to overload-currents . Etc .refer

 

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2011- Note : P/55. 411.4.7. Table – 41.3. for the types & ratings of overcurrent-devices , listedmay be Used-instead of calculation . :icon_bs:


► Taken from , Old-notes . 16[SUP]th[/SUP] Edition .

Overload-provisions are met , if the setting of the protective-device: ( In )

Exceeds the circuit-design-current . ( Ib )
Does Not-exceed the rating of the smallest-cable-protected .

The current for operation must not be greater than ( 1.45 times the rating ) of the smallest-cable-protected .

BS-EN-60898 . ( B –type ) requires a 32A Circuit-breakerto operate within one-hour when carryinga current of 40A .
Fig – 3.4. P/301 ... ( 5 x 32A = 160A) High-current-operation

Maximum-loop-impedance. ( Ia, Ief )

Amp ÷ current = sec .
32A ÷ 230v = 0.1
Zs ≤ Uo / Ia .
Zs ≤ 230 / 160 .
Zs ≤ 1.4375Ω ... 41.3 , Zs - 1.44Ω

“ Instantaneous“ which is actually within ( 0.01 s ) 10mS . ( Current for time. 0.1s to 5s. ) Fig – 3.4. P/301

Fig . 3A4 . 3A6 .

B . 3 x 6A = 18A or 5 x 6A = 30A
C . 5 x 6A = 30A or 10 x 6A = 60A
D . 10 x 6A = 60A or 20 x 6A = 120A

When does a Circuit-breaker trip . B , 3 - 5 .

The Circuit-breaker-side of the RCBO. BS-EN-61009-1 , Fig . 3A4 . 3A6 . Overcurrent-characteristics

433: P/81 . Protection against ,Overload-current .

Reason : Overload-protection is to safeguard-Conductors & Cables .
Overload-protection is related to the ,Current-carrying-capacity of the cables. Etc

 

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Re-cap : - Regulations 522.6.101 / 522.6.102 , 413.3 , 314.1 & 701 cover all applications for RCDs

 

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Extracts . taken

Health and Safety at Work Act 1974

The Health and Safetyat Work Act 1974 and the Electricity at Work Regulations 1989 are statutorydocuments and non-compliance constitutes a criminal offence.

Electricity at Work Regulations 1989

Because of the widerange of work covered by the regulations, the requirements are framed ingeneral terms , the Memorandum of Guidance on the above regulations, a clearcase is made for using RCDs as an additional safeguard forearthing ( Reg - 8 ). Also under clause 12 ( Isolation ), it advises that the use of , RCDs will meet the provision of ( Isolation) check – Table 53.4.

 

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P/52 . Fault Protection . Some-facts . :icon_bs:

Chapter 411.1 (ii)States that Fault-protection is provided by protective-earthing, protective-equipotential-bondingand automatic-disconnection in case of a ( fault ) in accordance with Regulations , 411.3 to 411.6.

 

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Some-facts .

P/55 . Chapter- 411.4.7 , confirms that if an RCD isused to provide fault protection, it is not necessary to undertake the disconnection-calculations required forovercurrent-devices. The values specified in Table 41.3 may be used. An RCD will always trip within ( 0.4seconds ) :30:

 

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RCD will trip on . ( Ief ) 0.04s , under earth-fault-conditions .

 

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Drawing you attention To , P/230

Section – 710

MEDICAL-LOCATIONS :

710.1. Scope

This section applies toelectrical installations in medical locations to ensure the safety of patientsand medical staff. These requirements, in the main, refer to hospitals, privateclinics, medical and dental practices, healthcare centres and dedicated medicalrooms in the workplace.

NOTE 2 : Where applicable, thisStandard can also be used in Veterinary-clinics. ◄ :aureola:

 

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Lighting-circuits : - Inthe 16[SUP]th[/SUP]-Edition,lighting circuits would not use 30mA RCDs for additional protection becauseof the possibility of nuisance tripping, leading to the potentially dangerousscenario of people being left in the dark.

In the 17[SUP]th[/SUP]-Edition, therequirement of Regulation 522.6.7 - 522.6.102 . means that such additional RCD protectionapplies also to lighting-circuits.To eliminate the risk of both lighting circuits going off simultaneouslybecause of nuisance-tripping,

 

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Designing for the 17th Edition . 2008: 2011: Wording . ( Impact-protection )

Impact-protection :

the requirements of Regulation - 522.6. 101. and Regulation - 522.6. 102. regarding ( Impact-protectionof cables ) because these Regulations affect the design of the wholeinstallation

Regulation - 522.6.101. concerns the protection against impactof cables concealed in a wall or partition at a depth of less than 50mmfrom the surface of the wall orpartition, which is likely to be the case in domestic premises. Regulation - 522.6.101. Etc .

 

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Useful-junk , RCDs :yes:

Residual Current Devices,

It is not clear when and by whom the first RCDwas developed, but it certainly appeared on the market in the 1950s and was initially used by some utilitycompanies to fight “ energy-theft” due to the use of currents from , phase to earth instead of phase to neutral.

 

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With-anything, We have consequences . in our Own-Actions :icon_bs:
[h=2]BS-7671-2008: 2011: Conduct for Inspectors , [/h]Inspector(s) must uphold the highest-professional-standards in their work. ( That’s why we are Not-Cowboys )

Thetest , entitled ‘ Knowledge of Fundamental “ InitialVerification “

Preparation for inspection .
Understanding-inspection,
providesan explanation and exploration of the new-inspection-methodology; insights intohow inspection is planned and undertaken

This ,Guidance-Note is concerned-principallywith Part - 6 of BS-7671: , Inspection & Testing. ( Refers also to , Tests)
Inspection . ( It summarises the judgments’ inspectors will makeduring-inspection ) which is the first-line of defense . “ Visual-inspection “ .
Testing .
• Understanding- the equipment to be used , its rating & the characteristics of theinstallation it is proposed to use theequipment-upon .
• Checkingthat the instrument(s) to beused-conform to the , appropriate British-Standard-Safety-Specifications ,( These . being BS-EN-61557-? )

Who is this bookfor: 2392-10 , 2394 , 2395 .
GN-3 :isof interest to all those who are involved with specifying, planning or carryingout the Inspection & Tests onelectrical installations BS-7671. The market includes consulting-engineers,electricians, electrical-installers, inspectors & technicians and can also serve as a guide forsurveyors.
This ,Guidance-Note is concerned-principallywith Part - 6 of BS-7671: , Inspection & Testing .
GN-3 Inspection and Testing is an essential guide
BS-7671 (The IET Wiring Regulations) 17th EditionAmendment No 1, the national-standard to which all ( domestic & industrial ) wiring must conform.
H&S . P/12 . BS-7671-2008:likely to achieve-conformity with the relevant-partsof the , Electricity at work-Regulation(s) – 1989 . Etc
Ensure the Health& Safety of inspector(s) while on their premises , & (Customer(s)

Contents:
Initial verification . ( Purpose - off ) GN-3. P/15
Periodic-inspection & testing ... ( Existing-installations ) ( Purpose - off ) GN-3. P/61
Test-instruments , ( Verification- British-Standard-Safety-Specifications ) particular-attention should be paid tosafety-aspects associated with any Tests.
Forms. The Client : Certificates & Report(s) by ( Verification-Reporting )

In a Court-of-Law . EIC , will indicate the , responsibility for , Design , Construction , Inspection & Testing , (With the reminder off ) Whether in relationto , New-work , or further-work on an , Existing-installation.

Initial verification : ( Safety-Certificate) EIC . :deal:
Periodic-inspection: ( Report ) EICR . Mainly – Condition. In the Eye’s of BS-7671: Am I safe to Use . :deal:
Minimise-disruption . ( Periodic-inspection)

 

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Council will ask you for .. ( Heat or Ionisation , Optical ) Alarms . Accordance with BS-5839-6 .

( if No ) fire protection system installed in the ( Flat(s) Provide & install a .. Grade ( D ) LD3 electrically operated fire detection system with an interlinked smoke alarm & a heat alarm in the flats .
Grade D
The mains-supply to smoke & heat alarms should either be a single independent circuit from the dwelling’s consumer-unit or a separately electrically protected regularly used local lighting circuit.

Domestic fire alarm systems, the minimum grade is ( D ) and therefore all new-builds will require smoke and heat alarms with a battery back up whether it's alkaline or lithium.

LD3 - alarms fitted in escape routes only e.g. hallway & landing/s. Etc .
Fire alarm systems are usually installed in dwellings to protect Life ( L )
Objective of category ( L ) systems is the protection of life , ( D ) means dwelling .

Grade D LD3 : protection of Life / means Dwelling
LD3 : A system incorporating detectors in all circulation spaces that form part of the escape routes from the dwelling ..

 

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Grades of system

A system of one or more mains powered smoke alarms, each with an integral standby supply. ( The system may, in addition, incorporate one or more mains-powered heat alarms, each with an integral standby supply )

Categories of system
LD3 - a system incorporating detectors in all circulation spaces that form part of the escape routes from the dwelling.

Hallways, Landings

Open Plan - Lounges, Sitting Room

( Heat alarm in Kitchen ) ... Heat rarely cause false alarm

( Ionisation sited away from kitchens )

( Optical sited away from bathrooms )

Commissioning
The system should be inspected. Electrical tests made to the mains supply circuit should include earth continuity, polarity, and earth fault loop impedance. Insulation tests should be made of all installed cables as required by BS-7671:

 

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What standard should I fit to !
BS-5839-6 : covers all domestic property types in the UK.

BS-5839-6: 2013 is the main standard for domestic standard for domestic fire alarm systems. It tells you everything you need to know about design, installation, testing and maintenance.

• Building Regulations refer to this standard
• Local Authorities, Housing Associations and Private Landlords have a “ Duty of Care ” to their tenants to fit to this standard
A Building Control Officer will be looking for an alarm system to this standard (as a minimum) before signing off on the property
• Building Regulation’s say to follow BS-5839-6 so if in doubt, ( follow this standard and you should be covered )

There are different Building Regulation’s for England and Wales, Scotland and Northern Ireland

 

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Categories of fire alarms system & mixed system in dwellings .
Category ( PD ) a fire detection & fire alarm system intended for the protection of .. ( Property )
this category is further sub-divided into :

Category ( PD1 ) a system installed throughout the dwelling, incorporating detectors in all rooms & areas in which fire might start , other than toilets , bathrooms & shower .

Category ( PD2 ) a system incorporating detectors only in defined rooms or areas of the dwelling in which the risk of fire to property is judged to warrant their provision .
refer : clause 9 of BS-5839-6
Category ( P ) automatic fire detection and fire alarm systems principally intended for the protection of property. These are sub-divided into the following categories: P1 , P2 .

BS 5839: Pt.6 is primarily concerned with saving lives and reducing injuries. However, it does contain within it recommendations for helping to reduce property damage too. Good fire safety practice and adherence to the Code can give the best possible early warning of fire and so reduce the financial impact as well as human suffering.

Although principally concerned with systems for the protection of life ( Category LD, covering ‘ Life ’ & ‘ Dwellings ’ ), it also offers guidance on property protection ( Category PD )

 

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Fire Alarms in Dwelling 2013

The installation of automatic smoke detectors is, effectively, required in new dwellings to satisfy Building Regulations. .. Grade D LD3

What are various grade systems

The BS-5839: Pt.6 standard places different alarm types into grades simply described as follows:

• Grade A - a system of detectors and sounders with control and indicating equipment (a panel & perhaps call points).
• Grade B - a similar system to Grade A with some minor amendments.
• Grade C - detectors and sounders, or smoke alarms, with some control features.
• Grade D - mains smoke & heat alarms with a battery back-up supply.
• Grade E - mains only smoke & heat alarms.
• Grade F - battery only smoke & heat alarms.

 

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You may come across it as .. “ reasonably-practicable “

The two terms mean essentially the same thing and at their core is the concept of “ reasonably practicable “

“ reasonably practicable “ this involves weighing a risk against the trouble, time and money needed to control it.
Thus, ALARP describes the level to which we expect to see workplace risks controlled.

2013 / SFAIRP is short for ( “ So far as is reasonably-practicable ” )
2013 / ALARP ( “ As low as reasonably-practicable ” )

is the term most often used in the Health and Safety at Work etc Act and in Regulations.

Self-employed persons have a general duty in the Health and Safety at Work Act to conduct their undertakings in a way that ensures, so far as is reasonably-practicable, that they, and any others affected by what they do, are not exposed to health and safety risks.

Reasonably-practicable
If the regulation is to be met ‘ so far as is reasonably-practicable ’ , then risks, cost, time, trouble and difficulty can be considered.

Initial-Verification

Within this set of Standards Regulation 610.1. States :

Every installation shall , during erection and on completion before being put into service be inspected & tested to verify , so far as reasonably-practicable , that the requirements of the regulations have been met ,

This regulation of course applies not only to new-installations , it also applies to additions & alterations to existing installations .

The inspection & testing of new-work is known as , Initial Verification .
As the regulation suggests , this Initial verification commences at the same time as the installation work continues and carries on through the duration of the work .

P/36 . Verification
All measures by means of which compliance of the electrical installation with the relevant requirements of , BS-7671: are checked , comprising inspection , testing and certification .

( EAWR 1989 ) is not only for new-installations . Periodic inspection . ( relevant to existing-installation )

BS-7671: Regulation 621.1. States that :
“ Where required , periodic inspection & testing of every installation shall be carried out in accordance with Regulation’s 621.2 / 5 . in order to determine , so far as is reasonably-practicable , whether the installation is in a satisfactory condition for continued service “

Key / facts : HSWA 1974 & EAWR 1989 both have the word ( Work ) in them and of course that reflects that they are intended for use in the ( work-place )

BS-7671 Regulation 114

Safety first - ( Isolation )
We must ensure the disconnection and separation of electrical-equipment from every source of supply and that this disconnection and separation is secure.

 

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Duty holder

Duty holder, this phrase recognizes the level of responsibility which electricians are expected to take on as a part of their job in order to control electrical safety in the work environment. Everyone has a duty of care, but not everyone is a duty holder.