NCC 2019 Volume One
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Specification E2.2a Smoke detection and alarm systems
1. Scope
This Specification describes the installation and operation of automatic smoke detection and alarm systems.
Intent
To state that Specification E2.2a relates to the installation and operation of automatic alarm systems.
Automatic smoke detection and alarm systems
Specification E2.2a covers the technical requirements for smoke detection and alarm systems, including such detection as is necessary to activate smoke control systems.
2. Type of system
A required automatic smoke detection and alarm system must be provided in accordance with the following:
(a)
(b)
Class 3 buildings—
(i)
(ii)
(c)
Class 5, 6, 7, 8, 9b and 9c buildings— a smoke detection system complying with Clause 4.
(d)
Class 9a health-care buildings —
(i)
where more than 6 bed patients are accommodated— a smoke detection system complying with Clause 4; or
Intent
To specify compliance requirements for required automatic smoke detection and alarm systems.
Types of smoke detection and alarm systems
Clause 2 covers smoke detection and alarm systems directly referenced in Tables E2.2a and E2.2b. The application of smoke detection to smoke control systems is addressed in Clause 6.
Clause 2 indicates the types of system, in terms of smoke alarm and/or smoke detection, applicable to various Classes of buildings. A smoke detection system is considered necessary in certain Class 3 and Class 9a buildings to facilitate system monitoring as required by Clause 8 .
Smoke alarm systems
Smoke alarm systems are required in:
- Class 2 buildings;
- smaller Class 3 buildings (see Clause 2(b) regarding larger Class 3 buildings);
- Class 4 parts; and
- smaller Class 9a buildings (see Clause 2(d)(i) regarding larger Class 9a buildings).
Smoke detection systems
Smoke detection systems are required (and in some cases are the sole requirement to satisfy smoke hazard management provisions) in:
- Class 2 buildings;
- smaller Class 3 buildings;
- larger Class 3 buildings;
- Class 4 parts;
- Class 5–8 and Class 9b buildings (note that a smoke detection system complying with Clause 4 and not a smoke alarm system complying with Clause 3 is required in these buildings);
- smaller Class 9a building (see Clause 2(d)(i) regarding larger Class 9a buildings);
- larger Class 9a buildings (note that a smoke detection system complying with Clause 4 and not a smoke alarm system complying with Clause 3 is required in these buildings); and
- Class 9c buildings.
Combined systems
Combined smoke alarm and smoke detection systems are permitted (as specified) in:
- Class 2 buildings;
- smaller Class 3 buildings (see Clause 2(b) regarding larger Class 3 buildings); and
- Class 4 parts.
A smoke alarm system and a smoke detection system are only required to be installed when required by Table E2.2a or Table E2.2b.
3. Smoke alarm system
(a)
All Class 2 - 9 buildings—
(i)
A smoke alarm system must—
(A)
consist of smoke alarms complying with AS 3786; and
(B)
be powered from the consumer mains source.
(ii)
In kitchens and other areas where the use of the area is likely to result in smoke alarms causing spurious signals—
(A)
any other alarm deemed suitable in accordance with AS 1670.1 may be installed provided that smoke alarms are installed elsewhere in the sole-occupancy unit in accordance with Clause 3(b)(i) and Clause 3(b)(ii); or
(B)
an alarm acknowledgement facility may be installed, except where the kitchen or other area is in a building protected with a sprinkler system complying with Specification E1.5 (other than a FPAA101D system), the alarms need not be installed in the kitchen or other areas likely to result in spurious signals.
(b)
Class 2 or 3 buildings or Class 4 parts of a building — In a Class 2 or 3 building or Class 4 part of a building provided with a smoke alarm system, the following applies:
(i)
Alarms must be installed within each sole-occupancy unit, and located on or near the ceiling in any storey—
(A)
containing bedrooms—
(aa)
between each part of the sole-occupancy unit containing bedrooms and the remainder of the sole-occupancy unit; and
(bb)
where bedrooms are served by a hallway, in that hallway; and
(B)
not containing any bedrooms, in egress paths.
(ii)
Where there is more than one alarm installed within a sole-occupancy unit, alarms must be interconnected within that sole-occupancy unit.
(iii)
Subject to (iv), alarms must be—
(A)
installed in public corridors and other internal public spaces, located in accordance with the requirements for smoke detectors in AS 1670.1; and
(B)
connected to activate a building occupant warning system in accordance with Clause 7.
(iv)
In a Class 2 or 3 building or Class 4 part of a building protected with a sprinkler system complying with Specification E1.5 (other than a FPAA101D system), alarms are not required in public corridors and other internal public spaces.
(c)
Class 9a buildings — Smoke alarms must—
(i)
installed in every room, public corridor and other internal public space; and
(ii)
located in accordance with the requirements for smoke detectors in AS 1670.1; and
(iii)
interconnected to provide a common alarm; and
(iv)
have manual call points installed in evacuation routes so that no point on a floor is more than 30 m from a manual call point.
Intent
To specify requirements for required automatic smoke alarm systems.
Smoke alarm systems—Clause 3(a)
Smoke alarm systems must include smoke alarms which comply with AS 3786 (see Clause 3(a)(i)(A)).
Power to smoke alarm systems must come from the electrical power supply to that part of the building served by the smoke alarm system.
Use of other suitable alarms—Clause 3(a)(ii)
A smoke alarm can give false alarms if the atmosphere contains particles, such as steam or other vapours, which obscure vision. For example, in a kitchen or a bathroom these conditions may be present. Clause 3(a)(ii) therefore allows the use of a more suitable alarm in these locations. It is important that the alarm used is suitable for the location and type of fire likely to occur. The suitability of alarms can be determined by reference to AS 1670.1. The alternative of an alarm acknowledgement facility complying with AS 1670.1 provides occupants with an opportunity to mitigate the effects of spurious or unwarranted alarms.
Smoke alarms and residential buildings—Clause 3(b)
Clause 3(b) details the installation requirements for automatic smoke alarms in residential buildings (excluding Class 9 buildings).
Clause 3(b)(ii) requires alarms located within each sole-occupancy unit to be interconnected to provide a common alarm so that if one alarm sounds then other alarms in the sole-occupancy unit automatically activate, which will increase the likelihood of sleeping occupants being aware of the smoke. The word 'alarm' includes any type of alarm allowed under Clause 3(a)(ii)(A).
Smoke alarms located outside the sole-occupancy units, in public corridors and other common areas within the building, must be interconnected to provide a common building alarm in order to alert all building occupants to the potential hazard in the common evacuation routes.
In buildings which do not contain a sprinkler system complying with Specification E1.5, Clause 3(b)(iii) requires smoke alarms to be installed in public corridors and other internal public spaces. Such spaces would include public foyers, reception areas and enclosed carparks. However, these spaces would not include fire-isolated exits, as they are subject to separate smoke hazard management provisions under Table E2.2a.
Smoke alarms and health-care buildings—Clause 3(c)
The application of Clause 3(c) is limited by the provisions of Clause 2(d) to small health-care buildings, where not more than six patients are accommodated in beds.
Clause 3(c) requires smoke alarms to be installed in public corridors and other internal public spaces. Such spaces would include public foyers, reception areas and enclosed carparks. However, these spaces would not include fire-isolated exits, as they are subject to separate smoke hazard management provisions under Table E2.2a.
Interconnection of smoke alarms is required due to the level of compartmentation and the need to alert staff to help occupants who may be confused, non-ambulatory or otherwise dependent on assistance. Manual call points are also necessary in view of the nature of the occupancy.
4. Smoke detection system
(a)
All Class 2 - 9 buildings—
(i)
(ii)
In kitchens and other areas where the use of the area is likely to result in smoke detectors causing spurious signals—
(A)
any other detector deemed suitable in accordance with AS 1670.1 may be installed provided that smoke detectors are installed elsewhere in the sole-occupancy unit in accordance with the requirements for alarms in Clause 3(b)(i) and Clause 3(b)(ii); or
(B)
an alarm acknowledgement facility may be installed, except where the kitchen or other area is in a building protected with a sprinkler system complying with Specification E1.5 (other than a FPAA101D or FPAA101H system), the detectors need not be installed in the kitchen or other areas likely to result in spurious signals.
(b)
Class 2 or 3 buildings or Class 4 parts of a building — In a Class 2 or 3 building or Class 4 part of a building provided with a smoke detection system, the following applies:
(i)
Smoke detectors must be installed—
(A)
within each sole-occupancy unit, in accordance with the requirements for alarms in Clause 3(b)(i) and Clause 3(b)(ii); and
(B)
subject to (ii), in public corridors and other internal public spaces.
(ii)
In a Class 2 or 3 building or Class 4 part of a building protected with a sprinkler system complying with Specification E1.5 (other than a FPAA101D or FPAA101H system), smoke detectors are not required in public corridors and other internal public spaces.
(c)
Class 9a health-care buildings — The following applies in a Class 9a health-care building:
(i)
(A)
Photoelectric type smoke detectors must be installed in patient care area s and in paths of travel to exits from patient care areas; and
(B)
in areas other than patient care areas and paths of travel to exits from patient care areas, where the use of the area is likely to result in smoke detectors causing spurious signals, any other detector deemed suitable in accordance with AS 1670.1 may be installed in lieu of smoke detectors,
except where an area is protected with a sprinkler system complying with Specification E1.5, smoke detectors need not be installed where the use of the area is likely to result in spurious signals.
(ii)
Manual call points must be installed in evacuation routes so that no point on a floor is more than 30 m from a manual call point.
(d)
Class 9c buildings — In a Class 9c building—
(i)
remote automatic indication of each zone must be given in each smoke compartment by means of—
(A)
mimic panels with an illuminated display; or
(B)
annunciator panels with alpha numeric display; and
(ii)
if the building accommodates more than 20 residents, manual call points must be installed in paths of travel so that no point on a floor is more than 30 m from a manual call point.
Intent
To specify requirements for required automatic smoke detection systems.
Smoke detection systems—Clause 4(a)
Clause 4(a)(ii)(A) specifies the circumstances in which AS 1670.1 applies.
Clause 4(a)(ii)(B) specifies that the smoke detection system must activate a suitable building occupant warning system.
Use of other suitable detectors—Clause 4(a)(ii)
A smoke detector can give false alarms if the atmosphere contains particles, such as steam or other vapours which obscure vision. For example, in a kitchen or bathroom these conditions may be present. Clause 4(a)(ii) therefore allows the use of a more suitable detector in these locations. It is important that the detector used is suitable for the location and type of fire likely to occur. The suitability of detectors can be determined by reference to AS 1670.1. The alternative of an alarm acknowledgement facility complying with AS 1670.1 provides occupants with an opportunity to mitigate the effects of spurious or unwarranted alarms.
Residential buildings—Clause 4(b)
Clause 4(b) details the installation requirements for automatic smoke detection systems in residential buildings (excluding Class 9 buildings).
In buildings which do not contain a sprinkler system complying with Specification E1.5 (other than a FPAA101D or FPAA101H system), Clause 4(b)(i)(B) requires smoke detectors to be installed in public corridors and other internal public spaces. Such spaces would include public foyers, reception areas and enclosed carparks. However, these spaces would not include fire-isolated exits which are addressed in Table E2.2a, commercial storerooms, cleaner's rooms, service cupboards or the like.
Clause 4(b)(i)(A) references Clause 3(b)(i)and Clause 3(b)(ii) which require alarms located within each sole-occupancy unit to be interconnected to provide a common alarm so that if one alarm sounds then other alarms in the sole-occupancy unit automatically activate, which will increase the likelihood of sleeping occupants being aware of the smoke. The word 'alarm' includes any type of alarm allowed under Clause 3(a)(ii)(A).
Health-care buildings—Clause 4(c)
Clause 4(c) applies to all Class 9a buildings which have a smoke detection system. Clause 4(c)(i)(A) applies to both within the patient-care area and the path of travel after a person leaves the patient-care area.
Where an area within a health-care building is likely to cause spurious signals, and the area is protected with a sprinkler system complying with Specification E1.5, Clause 4(c)(i) provides a concession to the smoke detector requirements.
Manual call points are required in evacuation routes in view of the nature of the occupancy.
Residential care buildings—Clause 4(d)
In a residential care building, an automatic smoke detection system must be installed in accordance with AS 1670.1. Subject to Clause 4(a) of Specification E2.2a, Clause 3.27 of AS 1670.1 lists areas where detectors are required. Manual call points are also necessary in larger buildings in view of the nature of the occupancy.
5. Combined smoke alarm and smoke detection system
(a)
A Class 2 or 3 building or Class 4 part of a building provided with a combination of a smoke alarm system and smoke detection system in accordance with Clause 2 must—
(i)
be provided with a smoke alarm system complying with Clause 3 within sole-occupancy units; and
(ii)
subject to (b), be provided with a smoke detection system complying with Clause 4 in areas not within sole-occupancy units.
(b)
In a Class 2 or 3 building or Class 4 part of a building protected with a sprinkler system complying with Specification E1.5 (other than a FPAA101D or FPAA101H system), smoke detectors are not required in public corridors and other internal public spaces.
Intent
To specify requirements for combined smoke alarm and smoke detection systems.
Combined smoke alarm and smoke detection systems—Clause 5(a)
Clause 2 specifies the circumstances in which Clause 5 applies.
Clause 5(a)(i) requires smoke alarms which comply with AS 3786 to be located within each sole-occupancy unit in accordance with Clause 3.
In buildings which do not contain a sprinkler system complying with Specification E1.5 (other than a FPAA101D or FPAA101H system), Clause 5(a)(ii) requires smoke detectors which comply with AS 1670.1 to be installed in public corridors and other internal public spaces in accordance with Clause 4.
6. Smoke detection for smoke control systems
(a)
Smoke detectors required to activate air pressurisation systems for fire-isolated exits and zone pressurisation systems must—
(i)
be installed in accordance with AS 1670.1; and
(ii)
have additional smoke detectors installed adjacent to each bank of lift landing doors set back horizontally from the door openings by a distance of not more than 3 m.
(b)
Smoke detectors required to activate—
(i)
automatic shutdown of air-handling systems in accordance with Table E2.2b; or
(ii)
a smoke exhaust system in accordance with Specification E2.2b,
must—
(iii)
be spaced—
(A)
not more than 20 m apart and not more than 10 m from any wall, bulkhead or smoke curtain; and
(B)
in enclosed malls and walkways in a Class 6 building not more than 15 m apart and not more than 7.5 m from any wall, bulkhead or curtain; and
(iv)
have a sensitivity—
(A)
in accordance with AS 1670.1 in areas other than a multi-storey walkway and mall in a Class 6 building; and
(B)
not exceeding 0.5% smoke obscuration per metre with compensation for external airborne contamination as necessary, in a multi-storey walkway and mall in a Class 6 building.
(c)
Smoke detectors provided to activate a smoke control system must—
(i)
(A)
form part of a building fire or smoke detection system complying with AS 1670.1; or
(B)
be a separate dedicated system incorporating control and indicating equipment complying with AS 1670.1; and
Intent
To specify the smoke detection requirements applicable to smoke control systems.
AS 1668.1 systems—Clause 5(a)
Clause 5(a) covers smoke detection associated with AS 1668.1 stair pressurisation systems referenced in Table E2.2a. It requires the installation of additional detectors adjacent to each bank of lift landing doors. Lift shafts form one of the principal paths for smoke spreading between floors in a multi-compartmented building.
Location and sensitivity—Clause 6(b)
Clause 6(b) covers the location and sensitivity of smoke detectors associated with smoke control systems referenced in:
- Table E2.2b, regarding automatic shutdown of air-handling systems.
- Specification E2.2b, regarding the smoke exhaust system.
Activation—Clause 6(c)
Under Clause 6(c), smoke detectors which activate a smoke control system must:
- form part of the building’s AS 1670.1 smoke detection system or be a separate dedicated system; and
- activate a building occupant warning system complying with Clause 7, unless they initiate shutdown of an automatic air-handling system only, in which case they need not activate a building occupant warning system.
7. Building occupant warning system
Subject to E4.9, a building occupant warning system provided as part of a smoke hazard management system must comply with clause 3.22 of AS 1670.1 to sound through all occupied areas except—
(a)
in a Class 2 and 3 building or Class 4 part of a building provided with a smoke alarm system in accordance with Clause 3(b)(iii)—
(i)
the sound pressure level need not be measured within a sole-occupancy unit if a level of not less than 85 dB(A) is provided at the door providing access to the sole-occupancy unit; and
(ii)
the inbuilt sounders of the smoke alarms may be used to wholly or partially meet the requirements; and
(b)
in a Class 2 and 3 building or Class 4 part of a building provided with a smoke detection system in accordance with Clause 4(b), the sound pressure level from a building occupant warning system need not be measured within a sole-occupancy unit if a level of not less than 100 dB(A) is provided at the door providing access to the sole-occupancy unit; and
(c)
in a Class 3 building used as a residential care building, the system—
(i)
must be arranged to provide a warning for occupants; and
(ii)
in areas used by residents, may have its alarm adjusted in volume and content to minimise trauma consistent with the type and condition of residents; and
(d)
in a Class 9a health-care building, in a patient care area, the system—
(i)
must be arranged to provide a warning for occupants; and
(ii)
in a ward area, may have its alarm adjusted in volume and content to minimise trauma consistent with the type and condition of the patients; and
(e)
in a Class 9c building, the system—
(i)
must be arranged to provide a warning for occupants; and
(ii)
must notify staff caring for the residents of the building; and
(iii)
in areas used by residents, may have its alarm adjusted in volume and content to minimise trauma consistent with the type and condition of residents.
Intent
To specify the application of building occupant warning systems.
Residential buildings—Clauses 7(a) and (b)
Because of the protection provided by the fire compartmentation of sole-occupancy units in residential buildings, it is not mandatory for a building occupant warning system to have sounders or speakers installed within each sole-occupancy unit. Accordingly, Clauses 7(a) and (b) provide for the sound pressure levels to be measured at the entry to each sole-occupancy unit.
Residential care and health-care buildings—Clauses 7(c) and (d)
Clauses 7(c)and (d) provide for the warning signals to be modified in certain areas within residential care and health-care buildings to minimise trauma to occupants who may be confused or immobile. However, in such instances, adequate warning must always be available to staff, carers, employees and the like.
Class 9c buildings—Clause 7(e)
Clause 7(e) requires warning signals to be modified in certain areas within Class 9c buildings to minimise trauma to residents who may be confused or immobile. However, in such instances, adequate warning must always be available to staff, carers, employees and the like. Residential care facilities may contain more than one building. Nevertheless, staff are required to be notified irrespective of their location.
Occupiable outdoor areas
Clause 7 requires a building occupant warning system provided as part of a smoke hazard management system to sound through all occupied areas. An occupiable outdoor area is part of a building, therefore a required occupant warning system must sound in an occupiable outdoor area.
Additional provisions in E4.9
The separate provisions under E4.9 are for emergency warning and intercom systems for emergency purposes in certain buildings.
8. System monitoring
The following installations must be connected to a fire alarm monitoring system connected to a fire station or fire station dispatch centre in accordance with AS 1670.3:
(a)
A smoke detection system in a Class 3 building provided in accordance with Clause 2(b)(i) or Clause 2 (b)(ii).
(b)
A smoke detection system in a Class 9a health-care building, if the building accommodates more than 20 patients.
(c)
A smoke detection system in a Class 9c building.
(d)
Smoke detection in accordance with Clause 6 provided to activate—
(i)
a smoke exhaust system in accordance with Specification E2.2b; or
(ii)
smoke-and-heat vents in accordance with Specification E2.2c.
(e)
An automatic fire detection and alarm system required by Table E2.2a for large isolated buildings subject to C2.3.
Intent
To specify the system monitoring requirements in high risk occupancies.
High risk occupancies
Clause 8 specifies the system monitoring requirements in high risk occupancies, to enable a timely and appropriate response by the local fire brigade to emergencies in such buildings as:
- certain residential, health-care and aged care buildings;
- shops and assembly buildings provided with mechanical or natural smoke extraction systems; and
- large uncompartmented factories and warehouses.
The Standard referenced for the alarm monitoring system is AS 1670.3.