Basement firefighting

Question 1

Basement incidents

Can you list the hazards that can be encountered when fighting fires in basements?

Answer 1

• metabolic heat stress
• high temperatures.
• fire growth within the compartment giving rise to backdraught and flashover
• uncontrolled ventilation occurring
• complex layout
• limited access and egress
• cramped conditions and poor ambient lighting conditions
• entanglement in loose cables.
• poor housekeeping leading to high fire loadings.
• storage within basements
• storage of hazardous materials without suitable signage.
• utility intakes such as high voltage electrical installations, gas and/or oil intake/storage.
• difficulty in maintaining effective communications

Question 2

Basement incidents

If sectorisation of a basement in a high rise was appropriate, could you sketch how it would look?

Answer 2

Question 3

Basement incidents

How may pavement and stallboard lights be identified?

Answer 3

These panels may have a different colour glass so they are recognisable

Question 4

Basement incidents

If tasks are required to be carried out elsewhere in the building i.e. rescue, what should the IC ensure?

Answer 4

The location and severity of the fire must be confirmed and the IC is satisfied it can be tactically controlled,

Question 5

Basement incidents

Prior to committing crews at a basement incident, What action should the IC consider to improve conditions for firefighters being comitted?

Answer 5

The IC should consider ventilation

Question 6

Basement incidents

The incorrect use of ventilation systems at a basement incident can have what affect?

Answer 6

• adversely affect any persons involved
• result in rapid or uncontrolled fire spread
• lead to backdraught conditions.

Question 7

Basement incidents

Prior to committing crews at a basement incident, What action should the IC consider?

Answer 7

Consider ventilation

Question 8

Basement incidents

What ‘En-route’ actions should be carried out when mobilised to a potential basement incident?

Answer 8

• ensure all personnel are rigged in full firefighting PPE.
• information received en route must be passed to all personnel and other take appliances.
• full use must be made of MDT operational information systems.

Question 9

Basement incidents

What are the considerations to be taken into account before considering ventiation of a basement incident?

Answer 9

The adverse impact this may have on persons involved in the premises

Question 10

Basement incidents

Once the IC has committed BA teams to the basement area, What message should be sent to Brigade Control?

Answer 10

“Basement procedure implemented”

Question 11

Basement incidents

What are pavement and stallboard lights?

Answer 11

Pavement and stallboard lights introduce some natural light into basements and provide a means of ventilation.

Pavement lights are horizontal and are strong enough for pedestrians to walk on. They are made of thick glass panels, set in metal or concrete frames

Pavement lights, which can be opened from the inside, often have breakable glass panels set near the catches

Question 12

Basement incidents

Before committing BA crews to a basement what must be secured?

Answer 12

Prior to committing BA teams a suitable, sufficient and sustainable water supply.

Question 13

Basement incidents

What equipment is available to us to help us locate both the seat of fire and casualties.

Answer 13

Question 14

Basement incidents

What is a ‘smoke extract’ and what are the potential hazards associated with them during a basement incidents?

Answer 14

Some basements and sub-basements are ventilated by smoke extracts. These are shafts or openings that lead from the basement to open air. The rate of smoke and fire gases produced at an underground fire could exceed the extracts’ limited capacity.

Question 15

Basement incidents

What is the ‘Operational procedure’ for a basement incident?

Answer 15

• IC to remain at surface level, unless preplanning dictates otherwise.
• Consider early request for additional resources.
• Consider availability / use of fixed installations.
• Consider requesting attendance of senior fire safety officer.
• Locate seat of fire from outside building if possible.
• Consider early appointment of safety officers and sectorisation.
• Early consideration of implementing Stage II BA control and the use of EDBA.
• Prior to committing BA teams consider options for ventilation.
• Ventilation only carried out on instruction of IC.
• Consult with responsible person on options for ventilation.
• Consider the impact of ventilation on fire spread and persons involved.
• Prior to ventilation position covering jets at openings.
• Basement must not be ventilated whilst BA teams are committed.
• Monitor the effects of ventilation.
• Minimum number of personnel committed to basement area.
• Ensure weight of attack (45mm jet minimum) is appropriate and adequate support jets (45mm minimum) are in place at all times to protect access and egress routes.
• BA teams may need to descend through a ‘thermal barrier’ to gain access, a branch set to spray should be considered to provide protection from heat/smoke.
• Maintain clear egress routes from basement.

Question 16

Basement incidents

What is the heat barrier?

Answer 16

The temperature at a basement fire can rise to a higher level than would normally be encountered because of the lack of ventilation. The entrance to the basement always gets much hotter than the basement floor. As the smoke and fire gases are hotter than the surrounding air they will rise, making the staircase and entrance to the basement act like a chimney or flue.

Question 17

Basement incidents

What must be considered before committing BA crews elsewhere to the fire?

Answer 17

Any benefit to be derived from committing personnel beyond the fire and/or elsewhere in the building must be properly assessed and then balanced against the risks present before undertaking such tasks.

Question 18

Basement incidents

What BA entry control stage is basement procedure?

Answer 18

Stage 2 unless the IC’s risk assesment does not deem it necessary

Question 19

Basement incidents

What must the IC ensure that when commiting crew to a basement?

Answer 19

• BA teams committed to basements have a sufficient weight of attack (minimum of 45mm jet)
• access and egress routes are kept clear and suitably protected
• consideration of stage 2 BA
• consideration of EDBA
• consideration of guide lines is for complex basements

Question 20

Basement incidents

How many wears can you have at a basement incident?

Answer 20

BA teams should not be re-committed to a basement unless in exceptional circumstances. IC should consider early reliefs

Question 21

Basement incidents

What on ‘On arrival tactics’ should be implemented at a basement incident?

Answer 21

• attend main entrance or predetermined RVP.
• liaise with responsible person, gather information.
• conduct initial assessment of building.
• BA crews with 45mm jet
• back up BA crew with 45mm jet
• consider evacuation of adjacent properties
• consider ‘making up’ the incident

Question 22

Basement incidents

What must the IC ensure when crews are undertaking tasks in the building or compartment which are supplementary to direct firefighting?

Answer 22

The IC must ensure that their way out of the building is fully protected at all times by the deployment of sufficient additional BA teams, jets and equipment.

Question 23

Basement incidents

How could a smoke extract be identified?

Answer 23

The opening to a smoke extract is usually protected by a pavement or stallboard light. In an emergency, these can be broken with a sledge hammer or large axe. Smoke extracts are marked by small plates, usually just above or on the rim of the cover, with the words SMOKE EXTRACT TO BASEMENT’ or SMOKE EXTRACT TO SUB-BASEMENT’.

Question 24

Basement incidents

What ‘Preplanning’ is required for a premises where a basement incident could occur?

Answer 24

Personnel must be familiar with access, fixed installations and any predetermined actions applicable to risks on their station ground.

Question 25

Basement incidents

What possible fixed instalations could you expect to find at a premises with a basement?

Answer 25

• automatic fire alarms
• mechanical ventilation or smoke extraction systems
• falling mains
• sprinkler systems
• foam inlets
• as flooding systems e.g. carbon dioxide
• larger buildings may also be provided with protected shafts and firefighting lifts.

Question 26

Basement incidents

Where can we get Information ‘en route’ to a basement incident?

Answer 26

MDT

Question 27

Basement incidents

Where should the IC remain at a basement incident?

Answer 27

IC is to remain at surface level, unless preplanning arrangements have located a more appropriate location

Question 28

Basement incidents

Where could the IC get other imformation from on arrival to a basement incident?

Answer 28

• Automatic fire alarm panels
• Premises information boxes

Question 29

Basement incidents

Who should the commander of the first appliance in attendance try to locate?

Answer 29

‘Responsible person’ where available

Question 30

Basement incidents

Is it reasonable to assume that there will always be external signs of the presence of a basement?

Answer 30

Incident commanders should consider that the existence of basements may not always be externally obvious. Basements in commercial, retail and residential premises may not have visual clues such as stallboard or pavement light windows.

Question 31

Basement incidents

BA teams may experience difficulty in maintaining effective communications what is availble to us to help communications?

Answer 31

The use of a leaky feeder