voice - mike parsons

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BS 5839 Part 8: 2008Fire Alarm Voice Evacuation Systems



Fire Division Sales Director of ID Fire and Security Ltd

30 years’ experience in the UK fire and security industry

Member of the Institute of Sound and Communication

Engineers (ISCE)

Member of the Institute of Healthcare Engineering and

Estate Management (IHEEM)

About Mike Parsons



Presentation Overview

• What is a voice alarm system?

• Categories of voice alarm systems

• Standards

• System design considerations

• Questions



A Voice Alarm is the soundercircuit(s) of a Fire Detection

and Alarm System

What is a voice alarm system?



Why have a voice alarm system?

• Research has proven that in an emergency people will react without confusion orpanic if they receive a clear, intelligible message.

• Bells and sounders only give a warning, they do not indicate the nature of theemergency.

• Phased evacuation using clear, easily understood, pre-recorded messagesensures that even untrained personnel are evacuated speedily and efficiently.



A typical voice alarm system



Phased Evacuation - Typical Office Block or Hotel

ROOF7th floor

6th floor

5th floor

4th floor

3rd

floor2nd floor

1st floor

ground floor

BASEMENT 1

BASEMENT 2

ROOF7th floor

6th floor

5th floor

3rd

floor2nd floor

1st floor

ground floor

BASEMENT 1

BASEMENT 2

EVACUATEalert

alert

EVACUATE

EVACUATE alert

alert

alert

EVACUATE

EVACUATE

EVACUATE



V1 : Automatic evacuation (No microphone)

V2 : Live emergency messages(Automatic plus All Call Emergency microphone)

V3 : Zonal live emergency messages(Automatic plus Zonal Emergency microphone)

V4 : Manual controls(Automatic plus Zonal Emergency microphone & message control)

V5 : Engineered systems(e.g. Wembley Stadium, Ascot Racecourse)

Voice alarm system categories



V1 - Typically simple acoustic spaces NOT requiring an(All Call) Emergency mic. (a VA system may also be used)

Voice sounders

Inexpensive

Similar to normal sounders

Simple installation

No large equipment racks

If used must comply with EN54 Pt3 A2 :2006

ₓ Multiple messages need a separate controller

ₓ No facility for live speech

ₓ Cannot achieve intelligibility in difficult spaces



Extremely cost-effective

Full compliance with BS5839 Pt8

Compact design

No special interfacing

Connects to the detection loop Uses standard cause and effects

Emergency microphone input

Paging and music inputs

Natural sounding speech

V2 - Simple acoustic spaces requiring an (All Call)

Emergency microphone - single zone VA system

VA wall-mount amplifiers

AVAC - a single zone voice alarm system



V3 - V5 Simple / difficult acoustic spaces requiring a (Zonal)

Emergency microphone - multi-zone VA system

VA floor mount racks

INTEGRITY - a 2 to 64 Zone voice alarm system

Compliance with BS5839 Pt8

Facility for live announcements

Can be used for public address & music

Natural sounding speech

Can cope with difficult acoustic spaces

ₓ Can be considered expensive

ₓ Speaker design is seen as a black art

ₓ Complexity of interface to fire alarm

ₓ Equipment racks take up lots of space



Design, Installation, Commissioning and Maintenance

• BS 5839-8: 2008

Product

• EN 54-16: 2008 VACIE in force from April 2011 (incorporates EN54-4 PSU’s)

• EN 54-23: 2010 Visual Alarm Devices

• EN 54-24: 2008 Loudspeakers in force from April 2011• EN 54-3 A2: 2006 Voice Enhanced Sounders

• BS EN54-25: 2008 (Radio Linked Components)

Voice alarm standards



A PA/VA rackexample in a

Premier LeagueFootball Club

Stadium whichhas now been

replaced

This will not comply



1. What type of building is it?

2. What is the evacuation strategy?

3. How many emergency loudspeaker zones?

4. How many paging/music zones?

5. What input sources are required?

Emergency Microphones - All-call or Zonal

Emergency Messages - Alert, Evacuate, Test, Security or Custom Paging Microphones - All-call or Zonal

Background Music Sources- CD, Satellite Download, Tuner etc

6. What is the ambient noise level in each space in dBA?

This allows loudspeaker design, tapping / loading requirements

7. The reverberation time of any difficult spaces (i.e. atriums)To see if specialist design help is needed

Designing a voice alarm system



Voice alarm acoustics

ACOUSTICALLY EASY

(LESS than 75dBA Ambient / RT60 1.5 Sec - Little Echo)• Shop units• Office blocks• Hotels

ACOUSTICALLY DIFFICULT

(MORE than 75dBA Ambient / RT60 1.5 Sec - More Echo)Public areas of:• Shopping malls• Cinemas, theatres• Airports, railway stations• Swimming pools and leisure centres



Acoustic Design

When selecting loudspeakers for a particular application, there are two basic

requirements to take into account. 1) Sound Pressure Level (SPL) – How loud!

2) Intelligibility – How clear!

Output level should be such that messages can be comfortably heard by all people

with normal hearing in 95% of the area. The information must be intelligible (understood)



Sound pressure level (SPL) measured in decibels (dBA)

How loud - 1



How increasing the speech signal

above ambient noise improvesIntelligibility.

Speech signal to background noiselevel ratio should be:

At least 10dBA+

Level ofambient noise

How loud - 2



How the ambient noise level

can vary at a football match

If the ambient noise is likely to vary a lot consider ambient noise sensing

Used in applications such as: Exhibition Halls Baggage Reclaims Halls

How loud - 3



Ambient Noise/Reverberation - Easy Spaces

ApplicationTypical

ambient dBA

BS5839 Pt8

required + 10dBA

Reverberation timein seconds

Classroom (quiet) 56 to 65 66 to 750.5 to 1.2

Classroom (noisy) 64 to 72 74 to 82

Conference / meeting room 40 to 45 65+ 0.6 to 1.3

Corridor (uncarpeted, quiet) 45 to 55 65+0.5 to 1.2

Corridor (uncarpeted, noisy) 66 to 76 76 to 86

Corridor (carpeted) 25 to 32 65+ 0.3 to 0.7

Courtrooms 40 to 50 65+ 0.5 to 1.0Factories (control rooms) 70 to 75 80 to 85 0.5 to 1.0

Hotel bedrooms (TV off) 25 to 35 75+0.4 to 0.6

Hotel bedrooms (TV on) 60 to 70 75+

Library (quiet reading area) 35 to 45 65+0.5 to 0.8

Library (noisy reading area) e.g. reception 50 to 60 65+

Offices (cellular) Less than 60 m2 40 to 50 60+

0.4 to 0.9Offices (open plan) 50 to 70 65 to 80

Offices (noisy) 70 to 85 80 to 95

Restaurants 72 to 75 82 to 85 0.5 to 1.0

Shops/stores (quiet) 50 to 60 65+0.3 to 0.8

Shops/stores (noisy) 65 to 75 75 to 85



Ambient Noise/Reverberation - Difficult Spaces

ApplicationTypical

ambient dBA

BS5839 Pt8

required + 10dBA

Reverberation time inseconds

Bank or building society (public area) 51 to 64 65 to 74 0.8 to 2.0

Cafeteria (quiet) 55 to 65 65 to 751.0 to 1.8

Cafeteria (noisy) 65 to 78 75 to 88

Factory (light assembly) 80 to 85 90 to 95 1.5 to 3.0

Factory (heavy engineering) 95 to 105 105 to 115 Consult specialist

Kitchen (commercial) 65 to 75 75 to 85 1.0 to 2.0

Leisure centre (multipurpose halls) 80 90 0.9 to 1.6

Leisure centre (ice rinks, public session) 69 to 80 79 to 90 Consult specialist

Leisure centre (swimming, diving pools) 72 to 79 82 to 89 1.5 to 3.0

Plant room (quiet boiler) 66 to 72 76 to 82

0.7 to 1.5Plant room (noisy boiler) 76 to 86 86 to 96

Plant room (air handling) 84 to 87 94 to 97

Plant room (compressor) 89 to 93 99 to 103 1.0 to 1.5

Shopping mall 70 to 75 80 to 85 Consult specialistSports hall (quiet) 60 to 72 70 to 82

1.0 to 2.5Sports hall (noisy) 72 to 82 82 to 92

Sports hall (loud ball games) 78 to 93 88 to 103

Warehouse (quiet) 47 to 63 65 to 731.5 to 2.5

Warehouse (noisy) 63 to 80 73 to 90



• Intelligibility is measured using the STI(Speech Transmission Index) which has arange 0 to 1

• The minimum BS 5839 Pt8 requirement forintelligibility is 0.5 STI - this is not difficult to

achieve in simple spaces

• BS 5839 Pt8 says STI does not need to bemeasured unless it is disputed

How clear - 1



Subjective methods

• A trained speaker reads text, syllables orwords.

• Listeners write down what they believethey have understood.

Standardized Methods:• CVC (Consonant – Vocal – Consonant)

• SRT (Speech Reception Threshold)

• CIS (Common Intelligibility Standard)

All these methods are very costly & timeconsuming and therefore only used to verify

technical methods.

How clear - 2



Example of SPL reduction over distance

Standing

Floor

Sitting

What is the listening height?



Types of loudspeaker

Recessed Ceiling

Vandal Resistant Cabinet

Standard Cabinet

Industrial Projector

Standard Projector

Bi-Directional Projector

Column

IP 66 Rated Horn

Suspended Sphere / Pendant

Specific Stadium Application



Tapping / connecting loudspeakers

EOLD Amplifier

Important

Most manufacturers supply loudspeakers tapped at maximum and they almost always need to be tapped lower. And

may need to be altered at the commissioning stage

Spurs are not allowed

10W

5W

2.5W

1.25W

Common

POWERTAPPING



What kind of loudspeaker?

VA Loudspeakers have to comply with BS5839 Pt8 which requires:

• Terminal blocks (usually ceramic) that are able to withstand a similar temperaturefor a similar duration to that of the interconnecting cable for example:

• 830ºC (PH30 Standard cables) 930ºC (PH120 Enhanced cables)

• Recessed ceiling loudspeakers (when used) fitted with a protective non-combustible fire dome that is able to withstand a temperature of 850ºC.Note: the fire dome does not have to be completely sealed.



Recessed ceiling

loudspeaker

Cabinet loudspeaker

Steerable loudspeaker

(horn, projector,

pendant, etc)

Installing loudspeakers




Acoustically EASY (LESS than 75 dBA Ambient / RT60 1.5 Sec)

Ceiling Loudspeakers

For flush fitting into a Suspended

Ceiling (less than 4M). Provide even

sound distribution e.g. open plan office,

department stores and supermarkets etc.3 Metres from a wall and then 6 Metre Centres




Acoustically DIFFICULT (MORE than 75 dBA Ambient / RT60 1.5 Sec)

Pendant Loudspeakers

For retail/distribution

applications which

have high ceilings

and/or racking/aisles



Microphone Technique



Seek proof of competency

1. Member of the Institute of Sound and

Communication Engineers (ISCE)www.isce.org.uk

2. Member of the Institute of Acoustics (IOA)www.ioa.org.uk

3. A brand new course for fire industry

professionals to be launched inSeptember 2011.

http://www.isce.org.uk/

http://www.ioa.org.uk/

http://www.ioa.org.uk/

http://www.isce.org.uk/



Thank you for attending

ID Fire & Security Ltd Shepley House, Restmor Way,

Hackbridge, Surrey SM6 7AH

Tel: 020 8773 3377 Fax: 020 8773 4956Email: [email protected]

Visit our website at www.idfireandsecurity.co.uk

http://www.id-group.co.uk/

http://www.id-group.co.uk/

voice - mike parsons

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