X
تبلیغات
:: بهداشت ، ایمنی و محیط زیست در محیط کار ::  

بیان مطالب و مقالات،فیلم و پوستر های مربوط به رعایت قوانین بهداشت،ایمنی و محیط زیست در محیط کار



 

 

LADDERS

 

 

 

Firefighting & Rescue Training

  

 

for

The National Petroleum Company-Iran

 

  

 

 

 

 

 

 

 

 

 

 

 

 

 

The Fire Service College

Moreton-in-Marsh

Gloucestershire UK

 

 

 

 

LADDERS

 

Contents                                                                                                               Page

 

 

1          Key Information

 

1.1       Aims & Learning Outcomes                                                                        3

 

 

2          Primary Information

 

2.1       Terminology                                                                                               4  -  5

 

2.2       Criteria for Pitching Ladders                                                                       6

 

2.3       Ladders in the Fire Service                                                                         6

 

2.4       Bridging Ladders                                                                                          10

 

2.5       Safety Aspects                                                                                              11

 

2.6       Ascending and Descending                                                                        11

 

2.7       Taking a Leg Lock                                                                                        11

 

 

3          Supporting Information

 

3.1       Improvising a Step Ladder                                                                          12

 

3.2       Handling Ladders                                                                                         12

 

3.3       Hoisting a Ladder                                                                                         12

 

3.4       Using an Extension Ladder                                                             13

 

3.5       Use as a Stretcher                                                                                        13

 

3.6       Forming a Dam                                                                                             13

 

3.7       Technical Data                                                                                              14

 

 

 

 

 

 

 

 

 

 

LADDERS

 

1       KEY INFORMATION

 

1.1             AIMS AND LEARNING OUTCOMES

 

 

The aim of this session is to:

 

Introduce the student to all extension ladders used within the Service and the terminology used with these ladders.

 

 

At the end of the session the student will be able to:

 

·        List the standard terminology in relation to pitching ladders

 

·        List four criteria for pitching Fire Service Ladders

 

·        Identify the different ladders used in the Service

 

·        Identify the principle parts of a ladder

 

·        State the function, use and construction of all ladders used within the Service

 

·        State, and put into practice, the safety points and notes on extension ladder drills as detailed in the Fire Service Manual.

  

            


LADDERS

 

2       PRIMARY INFORMATION

 

2.1    TERMINOLOGY

 

Words of Command

 

         The following words of command are to be used during training and where applicable, at incidents.

 

 

         

Command

Action or meaning

 

 

Extend

To increase the overall length of a ladder

 

 

Extend to lower

To raise the extending portion of a ladder to clear pawls for lowering

 

 

Head in

To move the head of the ladder towards a building

 

 

Head out

To move the head of the ladder away from a building

 

 

Heel in

To move the heel of the ladder into the building

 

 

Heel out

To move the heel of the ladder away from the building

 

 

House

To reduce the overall length of a ladder

 

 

Pawls

To indicate when descending a ladder that the pawls are fitted on the next round below and the feet should be laced towards the centre of the round.

 

This command (along with ‘Step in’ and ‘Step out’) should be used during drills to accustom personnel to the procedure, particularly when performing rescue drills.

 

The order should be given when the leading foot reaches the round immediately above the hazard

 

 

Pitch

To erect a ladder against a building, e.g., ‘Pitch to the third floor’

 

 

Props – down

Used by the No 1 of a crew during the ‘High Wind’ procedure of a 13.5m ladder drill.  Once the ladder has been sited, the props are then rested on the ground to support it for extension.

 

 

 

 

 

 

 

 

Words of Command

 

Command

 

Slip

 

 

 

 

 

 

 

Action or meaning

 

To remove a ladder from the appliance

 

 

Stand from Under

·             To be used by anybody who has to lower equipment or drop debris from a height when there is a risk that it might strike someone.

 

·             When lowering items, personnel should ensure that no-one is immediately below.

 

·             Also to be used when equipment is accidentally dropped from a height.

 

 

Stand by to Lower

To be used when two or more firefighters are to take the strain in preparation to lower a heavy object.

 

 

Lower

After taking the strain the firefighters all lower simultaneously.

 

 

Stand by to lift

To be used when two or more firefighters are to take the strain to lift a heavy object

 

 

Lift

After taking the strain the firefighter all lift simultaneously

 

 

Step in

To indicate that the overlap of extension is reached when descending a ladder with extensions on the underside (see note on ‘Pawls’ above).

 

Step out

To indicate that the overlap of the extension has been reached when descending ladder with extensions on the face side (see notes on ‘Pawls’ above)

 

Under Run

To raise a ladder from a horizontal to a vertical position and vice versa.

 

 


2.2    CRITERIA FOR PITCHING FIRE SERVICE LADDERS

 

          Heel: positioned one third of the working height from the building

 

          Head: Standard pitch – positioned between three to five rounds clear of the cill

                     Cill pitch – positioned level or just below level of the cill

 

          Plumbing: not grater than 7 degrees from the vertical.

 

 

2.3       LADDERS IN THE FIRE SERVICE 

 

          All appliances carry two or three section aluminium short extension ladders.

 

Use:

·             When using the complete ladder each section may be extended to the limit determined by the stops fitted.

 

·      Each extension may be used individually, or as an adaptation to other equipment, e.g., part of a temporary dam, ‘A’ frame, or step ladder

 

·      Each extension is pawled to leave a minimum of three rounds overlap.

 

          9m Ladders

 

          Some appliances carry 9m or 10.5 ladders.

 

          There are two manufacturers of these ladders in use in the service (Bayley and Angus Sacol).

 

Bayley 9m Ladders

 

§         They are manufactured from high tensile aluminium alloy. The extending section runs on nylon or steel rollers in guide channels integral with the strings.  Claw-pendulum pawls are fitted which engage on a convenient and appropriate round of the main ladder, therefore applying the weight of the sliding extension to the main ladder rather than the extending line.

 

§         The sliding extension is operated from a 16mm line running over a top metal pulley.  Stops are provided on the main ladder to prevent over extension.  The extending line consists of the current length of line to allow for shrinkage.  This line should never be shortened or tied in a knot when the ladder is stowed.

 

§         Pivoted heel plates are fitted to each string of the main ladder and wooden plugs to the other open ends of all strings.

 

§         The ladder may be adapted for use as a step ladder, bridge, or can be split to separate individual ladders.

 

§         Whenever the ladder extension is separated from the pawls, on re-assembly, the ladder must be tested for correct operation.

 

 

2.3    LADDERS IN THE FIRE SERVICE

 

Angus Sacol 10.5m Ladders

 

§         This ladder is manufactured from heat treated and hardened aluminium alloy.

 

§         The extending section runs on nylon rollers in guide channels integral with the strings.  The ladder is fitted with double action automatic pawls with strong return springs to ensure positive action.

 

§         As an added safety feature the ladder is fitted with an automatic arrest device, which is identical to the one fitted to the AS 13.5m ladder.

 

§         The As 9m ladder may be bridged or split.  However, the splitting and re-assembling procedure is not as described in the Fire Service Training Manual (See S.I.S Tech 2/061).

 

§         A wheel assembly is fitted to locate the ladder on its mounting and also to allow the head of the ladder to facilitate even running against wall surfaces.

 

§         A velcro strap is fitted to the main extension of the ladder and secures the two section together.

 

Gantry

 

Two different gantries are in use within the service; a fixed roof gantry and Sacol sliding gantry.  After re-stowing, ladders must be checked for security.

 

         13.5m Extension Ladder

 

·        The 13.5m extension ladder is a three-section ladder carried on all WrL’s.

 

·        It is manufactured from heat treated and hardened aluminium alloy.  The two moving sections of the ladder run on nylon rollers in guide channels that form an integral part of the strings.  The rounds are square sectioned to prevent turning and the tread surfaces are serrated to give non-slip qualities.

 

·        An 18mm cotton/nylon rot-proof and non-hardening line running over the metal sheaves operates the upper section.

 

·        To prevent the middle and upper sections from ‘running out’ whilst carrying the ladder a 50mm nylon webbing strap is fixed to the fifth round of the main ladder and secured by Velcro.

 

 

·        Double action positive action automatic pawls with strong return springs are fitted to the first and top extension.

 

·        A wheel assembly is fitted to the head of the ladder to facilitate easy running against wall surfaces.


2.3   LADDERS IN THE FIRE SERVICE

 

 

Extending Line

Quadrants

Jack Beam

 

 

 

 

 

 

 

 

 

2.3    LADDERS IN THE FIRE SERVICE

 

 

·        Stability is provided by twin screw jacks attached to a robust stabilizer bar at the heel of the ladder permitting safe operation on uneven ground.  The jacks are fitted with 200mm diameter operating wheels with universal joints to the pads.

 

·        Tormenter poles (props) used for the structural support of the ladder and as an aid to handling are provided and fitted with universal joints at the head and metal spikes at the foot.  Clips on the main ladder hold the props in the fold-away position when not required and during transit.

 

·        Carrying handles are fitted to the head of the ladder and to the stabilizer bar.

 

·        The yellow mark on the props should be on the underside of the ladder facing up.

 

         Gantries

 

Two gantries are in use in the Service, a fixed roof gantry and a Sacol sliding    gantry.  After re-stowing, ladders must be checked for security.

 

 

         Roof Ladders

 

         Construction is of an aluminium alloy.  The two sections are of unequal length – the upper C-shaped hook with protective edging and small diameter wheels (120mm) are fitted in the head.  The ladder is held in the fully open position by positive spring-loaded locking pins, which engage automatically, when the ladder is opened up.

 

Note: It is important to ensure that the locking pins have fully engaged before the ladder is used.

 

         Five U-shaped ladder supports are fitted to the underside of the ladder to spread the load more effectively with the roof surface when the ladder is in use.

 

Roof ladders are used to gain safe access to pitched roofs.  Care must be taken to ensure the hook is properly secured on the roof reverse slope before mounting the ladder.  Although the ladder is of lightweight construction it can be unwieldy in high winds or on roofs of unusual construction, i.e., mansard roofs, deep valley, etc.

 

Roof ladders are not to be used in the vertical position, either as a free-standing ladder, or supported by the C hook.

 

         The ladder must not be used for bridging purposes.

 

         All tests to conform to Service Information System – Technical 1/036.

 

All defects should be reported to Technical Services for the ladder technician to effect repair.

 

2.3    LADDERS IN THE FIRE SERVICE

 

 

NOTES ON THE USE OF ROOF LADDERS

 

         Whilst it is not possible to cater for all the circumstances in which roof ladders may be used, the following points of guidance should be observed wherever practicable.

 

         An extension ladder should be pitched to a point slightly on one side of the position that a roof ladder is to be used.  The ladder should be extended, preferably about 5 round above the eaves, to enable a leg lock to be taken above eaves level.  Extra care should be taken when ladders are resting on plastic guttering.  (The weight of a ladder could cause damage to or flexing of the guttering resulting in the ladder becoming unstable).

 

         The roof ladder should be under run, hook uppermost, and positioned adjacent to the strings of the extension ladder on the side that it is to be used with the hook pointing towards the opposite string.  One firefighter should mount the extension ladder and ascend until they are able to place one arm between the fourth and fifth round of the roof ladder with the round resting firmly on their shoulder.  The firefighter should then continue to ascend to a point above the eaves when a leg lock can be taken with the leg opposite to the side that the roof ladder is being carried.

 

         The roof ladder should be transferred from the shoulder and, grasping both strings with the wheels resting on the roof, maneuvered towards the ridge at an angle of approximately 10 degrees away from the extension ladder.  Once the hook has passed beyond the ridge, the roof ladder should be turned over towards the extension ladder, and adjusted to ensure that the hook is resting firmly on the opposite side of the roof.

 

         When transferring to or from the roof ladder the sequence of movements must be foot, hand, hand, foot, with the nearest foot/hand being transferred first.

 

         When making up the roof ladder the reverse procedure must be adopted, one crewmember receiving the roof ladder when the firefighter on the extension ladder approaches the ground.  The roof ladder should be under-run and carried clear of operations.

 

2.4    BRIDGING LADDERS

 

 

            When bridging 9m ladders the following points of guidance should be observed:

 

·        There should be not less than 650mm of ladder on each side of the gap    being bridged.

 

·        When bridging, the overall extended length should not exceed 5m.

 

·        Except in an emergency, not more than one firefighter should be allowed on the bridged portion.

 

·        Safety lines should be used.  Personnel must be aware of the danger of losing their balance when crossing a bridged ladder.

 

·        Undue oscillation must be avoided when moving across bridged ladders (the turning over of the ladder is a common safety practice).

 

2.5    SAFETY ASPECTS

 

Firefighters will know the best angles at which to pitch a particular ladder but on the fireground the perfect angle is seldom possible.  Angles will vary: ladders may be nearly vertical where access is narrow, or semi-bridged over a basement area.  Where ladders are at fairly steep angles, on slippery surfaces or uneven ground, likely to be in situ for some time, or providing a line of retreat for a crew, firefighters should, for security, lash the ladder head to the building.  Whenever anyone is on a ladder there must be a firefighter at its heel to steady it.  S/he should place one foot on the bottom round or jack beam, bracing the other leg back on the ground and grasping the strings with both hands.  Firefighters will know the number of personnel allowed on a ladder at any one time under normal conditions.  They must however take into account factors at the time, eg., the angle and extension of the ladder, the ground conditions, whether the ladder is carrying any additional weight such as hose.

 

2.6       ASCENDING AND DESCENDING

        

         Ascending and descending ladder is a matter of rhythm and balance.  Firefighters should practice a smooth movement, which feels comfortable for the conditions and type of ladder.  The angle, extension and ‘whip’ of the ladder will dictate the method to be used.  Where the ground is firm and the ladder at its optimum angle, the firefighter should raise their hands and feet in unison (ie, left with left, right with right); they should keep their arms fairly straight, their body away from the ladder, their head slightly angled up to see where they are going and their feet sufficiently apart to give balance on that particular ladder.  As a general guide the firefighter should grasp the round level to his/her chest with palms down and thumbs underneath.  Obviously if the ladder is angled steeply, leaning back to the proper angle may be impossible owing to lack of space or may tend to pull the ladder from the building.  Conversely, at a shallow angle, the firefighter must bend their knees and arms and be more careful not to make the ladder roll.

 

 

2.7       TAKING A LEG LOCK

 

Often when working on a ladder a firefighter will need both hands free for such operations as directing a jet, handling small gear or pitching a hook ladder.  In these circumstances they must first take a leg-lock.  To do so they should grasp an appropriate round above that on which they are standing.  They should bend this leg using the inside of their knee and back of their calf to ‘lock’ himself/herself on.  If possible they should also bring the foot of this leg back through the rounds, placing their toes under the round immediately above the one on which they are standing.  If working to the right they should use their left leg to make the lock, if to the left their right.


 

LADDERS

 

3  SUPPORTING INFORMATION

 

 

 

3.1    IMPROVISING A STEP LADDER

 

Occasionally, when firefighters are working inside a building, they need to reach the centre of high ceiling or roof.  This is difficult with a conventional pitch.  A solution to the problem is to make the two sections of a ladder into a stepladder.  The ladders are extended horizontally on the floor to the required length, one being extended a round further than the other to allow them to interlock.  They are then lashed securely at the head and spread at the heel.  The spread should not be more than 2.5m for 9m ladders. It may be possible, according to type, to use one section of a short extension ladder as a fixed spreader for a 9m ladder.  The section is passed through the bottom rounds at the base of the spread ladders and the three sections are lashed together.  If a line is used as a spreader it should be attached by a clove hitch to about the third round of each ladder.  The ladders are then raised with one person footing each.

 

         To make a short stepladder, firefighters should use the sections of a short extension ladder lashed in a similar way, ensuring the spread is not more than 1m.  Usually one person is sufficient for footing.

 

3.2    HANDLING LADDERS

 

The ability to handle ladders safely and quickly under adverse conditions is the hallmark of a good firefighter.  The contrast between slipping, manoeuvring and pitching a ladder on a calm day with plenty of room and on firm ground and the same operations attempted about midnight, in rain, a strong wind, up a narrow alley, amongst industrial debris, is obvious.  Firefighters should practice usual pitches under whatever unusual conditions they can simulate.  It is especially important that they practice working in darkness or at least with the illumination of appliance searchlights only, as this would often be the case at incidents.

 

         Carrying ladders safely, especially under adverse conditions requires skill.  The Fire Service Drill book describes the basic methods, but firefighters should remember that, at large fires, they may have to step over numerous lines of hose, pass ladders across walls, negotiate narrow openings and twisting passages, and so on.  They should even practice carrying a ladder down a slope.  They must discover the problems they are likely to face and evolve satisfactory methods of dealing with them.

 

3.3    HOISTING A LADDER

 

Firefighters may find it necessary to haul up a ladder or section of a ladder to an upper floor or flat roof.  the easiest and safest method is to haul up the ladder vertically by line, preferably with a guy line attached to keep it clear of projections.  If the hoisting line is tied to the ladder approximately one third of its length from the top, this can help when the ladder is levered over a sill, balcony rail or roof edge.

 

 

 

3.4       USING AN EXTENSION LADDER

 

As already noted, extension ladders can be put to a variety of uses; the short extension ladder being particularly versatile.

 

3.5       USE AS A STRETCHER

 

When a stretcher is not available firefighters can use one section of a short extension ladder for carrying an injured person.  They should ensure they are practised in this operation and, for the following reasons, the practice should involve the use of a live body.

 

·                 It will teach them to secure the body properly to the ladder: neither a dummy nor an unconscious person can explain if the lines are too tight or too loose or the ladder unpadded and uncomfortable.

 

·                 A dummy cannot complain if its head or feet are not adequately supported.

 

·                 The weight and posture of a live body will be as at an incident.

 

·                 The manoeuvring of the ladder and patient will have to be more realistically careful, as at an incident.

 

3.6       FORMING A DAM

 

Circumstances sometimes arise when firefighters need a large open container for water e.g., to immerse items needing to be kept cool or during decontamination.  They can then use sections of extension ladders to form a dam.  They should lay three or four horizontally on one string and lash them together into a square or triangle.  They should then cover this framework with a salvage sheet, holding it in place by a running bowline passing round the outside of the dam at centre height.  When the sheet has settled and the water has reached the required level they should draw the line tight and secure the free end to the standing part with a rolling hitch.


3.7        TECHNICAL DATA

 

Short Extension Ladder

 

Height (housed)                    2.7 metres

Height (extended)                6.4 metres

Width                                     410mm

Weight                                   16 Kgs (approx)

 

9m Ladder Bayley

 

Height (housed)                     5.5 metres

Height (extended)                 9 metres

Width (main extension)       450mm

Width (top extension)          360mm

Weight                                    48 Kgs

 

10.5m Angus Sacol

 

Height (housed)                      6.25 metres

Height (extended)                 10.5 metres

Width                                       550 mm

Depth                                       185mm

Weight                                     63.5 Kgs

 

N.B    The length identification refers to the effective working height of its maximum extension and correct pitch on both Bayley and AS type ladders.

 

         Angus Sacol 13.5m

 

         Height (housed)                        5.8 metres

         Height (extended)                   14.9 metres

         Width (main extension)            66 cm

         Width (middle extension)        56 cm

         Width (top extension)              43 cm

         Weight                                     113 Kgs

 

         N.B    The 13.5m identification refers to the effective working height of its maximum extension and correct pitch.

 

         Roof Ladders

 

         Overall length, extended          4.5 - 5.4 metres

         Distance between rounds       30 cms

         Width outside strings              38 cm

         Weight complete                      16 Kgs.

 

         Each ladder is identified by a Service identification number riveted to the inside of a string.

+نوشته شده دردوشنبه 1386/09/12ساعت 2:20 PM توسط مهدی مجیری فروشانی |