Passive Fire Protection

PASSIVE FIRE PROTECTION

Lecturer: Dr. Yahya Bin Mohamad Yatim

Course: Building Services IICode course: SBEQ 2133

CLASS: 2SBEQ

Name : Nor Azmi Bin SuhardiMatric Number : B12BE0043Ic Number : 890404-08-5141

1.0 PASSIVE FIRE PROTECTION

Passive fire protection can provide an effective alternative to active systems

for protecting against vessel failure. This generally consists of a coating of fire

resistant insulating media applied to a vessel or steel surface. It is often used where

water or other active protection media supplies are inadequate, such as in remote

locations, or where there are difficulties with handling fire water run-off. Fire walls

are another form of passive fire protection that are used to prevent the spread of fire

and the exposure of adjacent equipment to thermal radiation. An important criterion in

deciding which system is most appropriate for fire exposure protection is the likely

duration of the exposure to fire as passive fire protection is only effective for short

duration exposure (1-2 hours).

1.1 Choice Of Passive Fire Protection

For the protection of vessels from fire exposure there are a number of types of

passive fire protection that can be applied.

mortar based coating

intumescent coating

sublimation coating

mineral fibre matting

earth mounds

The protective systems based on coatings are normally sprayed onto the surface

following mixing of the required components. A reinforcing glass fibre scrim or steel

wire gauze is applied to prevent cracking and peeling of the coating under fire

conditions and to provide additional strength to resist the impact of high pressure

water jets. The fire protective coating is further protected by a weather protective top

layer. The fire resistant performance of the coatings is dependent on the thickness of

the coating. Fibre matting systems consist of fireproof mineral fibre matting clad with

a protective galvanised steel sheet. The protective capability of the system is provided

by the poor heat conductivity of the system.

Earth mounds are commonly used in the LPG industry, where vessels are either

fully or partially buried in an earth mound. The presence of the earth mound

effectively prevents a fire from developing around the vessel.

Fire walls are sometimes employed in process and storage areas to prevent the

spread of fire and protect adjacent equipment from thermal radiation. These may be

an integral part of a process building or warehouse structure or may consist of a free-

standing wall specifically built for the purpose. Firewalls are normally built of brick,

concrete or masonry and the number and size of openings should be kept to a

minimum.

1.2 Performance And Maintenance Of Passive Fire Protection

Passive fire protection systems the operator should have supplier or

manufacturer information demonstrating that the fire protective system employed

meets defined performance criteria based on standard tests that replicate the fire

conditions likely to be encountered in the work place. Typically the criteria will be

that a protected surface will not reach a certain temperature in a defined time period

during a standard test. The protective system should meet the requirements of a pool

fire test such as that detailed in BS 476 'Fire tests on building materials and structures'

or a jet fire test such as that described in the HSE Technology Report 'Jet Fire

resistance for Passive Fire Protection Materials'.

The performance of passive fire protection systems can deteriorate in time due

to weathering and corrosion. Plant operational and maintenance activities may

damage or remove the fire protection. Additionally the protected surface itself can

corrode beneath the fire protection. Procedures should be in place to ensure that both

the passive fire protective system and the protected surface are regularly inspected

and repaired as appropriate.

2.0 PASSIVE FIRE PROTECTION REQUIRED IN UNIFORM BUILDING BY

LAW (UBBL) 1984

2.1 Definition

The Uniform Building By Law (UBBL) 1984 requires all buildings to have

minimum structural integrity based on its usage. Elements of construction can

only be effective as fire breaks if they have the necessary degree of fire resistance.

The three criteria of fire resistance:

a. Insulation

b. Integrity

c. Stability

Good building design with fire safety measures:

a. Provide adequate fire appliances, fire hydrants & other facilities to assist fire

& rescue personnel

b. Provide adequate fixed installation, where appropriate, for quick & effective

detection & extinguishment of fires

c. Designing & installing building services so that they do no assist the spread of

fire, smoke or toxic fumes

d. Designing & providing adequate and safe escape routes for the occupants of

the building

e. Selecting materials for the construction which will not promote the rapid

spread of fire or generate dangerous smoke

f. Subdividing buildings into compartments of reasonable sizes by means of fire

resisting walls & floors, providing fire stops to protect openings between

floors & compartments

g. Designing & constructing the exterior of a building so that fire is unlikely to

spread to it from another burning building.

2.2 Purpose Group

Where a building contains usage falling under different purpose groups and each is contained within compartment, by-law 215 of the UBBL 1984 allows the height of each part of the building housing a different purpose group, if they are vertically separated, to be considered separately for compliance with Schedule 6, 7, 9 in the UBBL 1984

2.3 Fire Appliance Access

Vehicular access to the exterior of a buildingis needed to enable high reach appliances to be used & to enable pumping appliances to supply water & equipment for fire fighting & rescue activities

Access requirement increase with building size & height

The table in By-law 140 (above) shows the proportion of the building perimeter that must be accessible to fire fighting appliances.

One-sixth

One-half

Three-fourth

Island site

2.3.1 Hydrants

Away from obstructions such as street furniture, phone booths, etc Not less than 2m from adjacent buildings & overhangs Between 0.61m to 2.4m from Fire Appliance Access Away from risks vehicular Not more than 90m apart from each other (in new buildings adjacent to

existing developments, a new hydrant or hydrants will have to be provided if there is no hydrant within 45m radius of the new building)

2.4 CONSTRUCTION USED FOR PASSIVE FIRE PROTECTION

2.4.1 Fire Rated Door

A fire door is a type of door or movable barrier used as part of a passive fire protection system within buildings to prevent the spread of fire or smoke between separate sections. It is usually the only means of allowing people to pass through a fire-resistant wall

Fire doors are designed to withstand fire, heat and smoke for a period of 20-minutes to 3 hours. Fire Doors are required to:-Be Self Closing: fire doors should have a door closure that pulls doors completely shut after the door has been opened-Have Positive latching: a positive latch locks a door in place so it can swing open.

Important of Fire Rated Door

Provides an effective barrier for the passage of fire and/or smoke Provide safe egress and increase protection for first responders Also serves for safety, security, accessibility, control, privacy & isolation Can also serve as environmental weather seal for heat, cold, moisture, dust and

debris

2.4.2 Fire Barrier

Passive fire protection products prevent the passage of fire, smoke and hot gases. Prevent the spread of fire, smoke and hot gases through a building by containing it in the compartment of origin.

Maintain the integrity of escape routes from a building. Reduce loss or damage to property from the effect of fire and smoke. Maintain pressure differential between compartments and ventilation channels.

Fire Barriers are probably one of the most critical and often overlooked areas of Fire protection. There are many forms of fire barriers some are the elements of the building itself such as the walls, floors, ceilings, etc., others may be nonstructural enclosures or partitions. Any barrier is only as good as its weakest link and it is critical that barriers are effective particularly during the evacuation phase of a fire.

There are many different requirements for Fire Barriers, with a variety of failure criterion. The effectiveness of a barrier can make the difference between a small localized fire to full scale disaster. The principal functions of a fire barrier are to prevent or reduce the spread of fire and or smoke spread. Fire barriers are often found on primary escape routes and are vital for the safe evacuation of a building or structure.

It is particularly important to consider the implications on fire barriers during building or plant modifications. It is not unknown for entire fire walls to have been totally negated by the apparently slight modification of, a shop frontage in a shopping mall, or even airport. Sometimes with tragically fatal consequences.

2.4.3 Fire Stopper

Fire Stop Strip is made from high density Rockwool stone wool and is permanently held in place by compression without the need for adhesive or intumescent mastic. It prevents the passage of flame and smoke through the void being fire stopped. For gaps greater than 100mm above masonry walls and partitions use AIM Partition Head Barrier.

Up to 4 hours fire rating No mastics or sealants required Reduces flanking transmission of sound by 9dB Non-combustible to EN15301-1 and classified A1

Complies with performance requirements of Class O of the Building Regulations

Ozone depletion potential of zero, no CFCs or HCFCs used in manufacture

Specification :

Lengths: 1200m Voids: 10 - 100mm

(For voids 100mm to 600mm use AIM Partition Head Barrier)

2.4.4 Partition Fire Barrier

Also known as fire rated partitions, fire partitions are freestanding walls or structures within a building that have the specific purpose of retarding the progress of a fire. While not the same as a fire barrier, a properly constructed fire partition can provide valuable time that increases the chances of evacuating the space before anyone is injured. In many jurisdictions, local building codes include specific criteria that a fire partition must meet in order to be included in a building design.

One of the major differences between a fire partition and a fire barrier is that the barrier is typically more stable than the partition. A barrier will normally extend through ceilings and floors, effectively creating another wall that the fire must work through before reaching the next section of the building. In contrast, a fire partition does not extend through a ceiling or floor and is not connected to the roof. In some cases, a partition may not even touch the ceiling within a given chamber, a factor that also tends to decrease the overall stability of the structure.

It is important to note that a fire partition is usually not expected to completely stop a fire from spreading. The idea is to slow down the progress of the fire so that anyone in the burning structure has a small amount of additional time to escape. The presence of the partition also means that the overall damage to the building is minimized, assuming that the fire is brought under control before the protective construction is breached.

Most jurisdictions that allow the inclusion of a fire partition in a new building design will require that the construction meet specific safety requirements that are found in local building codes. Those requirements may be specific in terms of the types of building materials used to construct the partition, as well as the thickness of the safety device and how it is anchored to the flooring. The idea is to make sure the materials do in fact aid in slowing down the progress of a fire, and that the partition is stable enough to avoid weakening the overall soundness of the structure.

There is some difference of opinion when it comes to determining if a fire partition is more effective than a fire barrier. Supporters tend to claim the partition offers protection that is at least as effective as the barrier, but will cost less to construct. Detractors note that the decrease in stability associated with a fire partition is not really worth the difference in construction costs, and could mean the loss of a few valuable seconds of time in the event that a fire does break out.