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ED

CIIUA is the Construction Industry Research and Information Association. It is a non-profit-distributing, private sector organisation carrying out research and CIRIA providing information for its members, who include all types

of

organisations

concerned with construction, including clients, professional practices, contractors, suppliers, educational and research establishments, professional

institutions, trade associations and central and local government.CIRIA focuses on providing best

practice guidance to professionals that is authoritative, convenient to use and relevant. Areas covered include construction practice, building design and materials, management and productiv-

ity, ground engineering, water engineering and environmental issues.Through active participation, CIRTA members choose research and information projects of most value to them. Funding contri- butions are sought from member subscriptions and from government and other sources on a project

by project basis. Detailed work is contracted to the best qualified organisation selected in competi-

tion, and each project is guided by a project steering group, which contains both individual specialists and representatives

of

different groups with experience or interest in the topic.

Core Programme Sponsorship. Core Programme members, who include many

of

the most

significant construction firms, choose the programme

of

research projects and obtain privileged

early access to results.

Construction lndustiy Environmental Forum. The Environmental Forum (run in partnership with BRE and BSRIA) is a focus for construction and related industries on environmental issues.

Members have free access to a substantial programme

of

workshops and seminars, monthly information bulletins, and publications arising from research undertaken.

Construction Productivity Network (CPN). CPN (a joint venture between CIRJA and BRE),

exists to promote the sharing and application

of

knowledge on construction productivity issues.

Members have free access to a substantial programme

of

workshops and seminars, a newsletter, and an annual conference.

Associates/Affiliates. Subscribers obtain copies

of

CIRIA open publications on favourable terms and get discounts on CIRIA seminars.

Purchase of Publications. CIRLA publications, together with selected publications from other sources, are available by mail order or on personal application.

Seminars/Conferences. CIRIA runs a number

of

events, often related to research projects or publications.

CIRIA News (quarterly detailedreports on CIRIA's research and information activities) and CIRIA Spectrum (occasional information on issues

of

wide interest) are available free on request. For further details, please apply to the Marketing Manager,

CIRIA, 6 Storey's Gate, Westminster, London SW1P 3AU

(3)

Special Publication 121 1995

Temporary Access

to

the

Workface

a

handbook

for

young professionals

prepared by

Sir

William Halcrow

&

Partners Ltd

and

Laing Civil Engineering

Construction Sponsorship Directorate Department of the Environment

Construction Industry Research and Information Association 6 Storey's Gate, Westminster, London SW1 P 3ALJ

Tel: 0171-222 8891 Fax: 0171 -222 1708 E-mail switchboard@ciria.org.uk

(4)

Summary

Appropriate provision

of

temporary

access

around

a

site

is

vital to

enable

the works to be

constructed, maintained, repaired

or

demolished

in a

sate and efficient way.

All

young

site

engineers, managers

and

supervisors

who

are

involved

in the

specification, installation

or

checking

of

temporary access

must

be aware

of

the

issues involved and

the basis

upon which choices

are

made.

This

site guide is intended

to be

of

benefit

to

designers, client representatives and students,

as well as

mature professionals

who wish

to

refresh

their

knowledge.

It is

the

purpose

of this site guide

to

bring together,

in

a

single volume,

the salient

points relating

to the

different

ways in

which access

may

be provided

on

a

construction site.

The guide

is

mainly

concerned with

access for

personnel rather than

for

plant,

equipment and materials. Extensive reference

has

been made

to

other

guidance documents which

deal

with

a

single

method

or item

of

plant in more

detail.

This guide

is

principally

for site

use;

it

fits

into

the pocket

of

a

jacket

and

much of the

information

is provided

in

tabular, graphical

or

checklist format

for

ease

of

use.

Temporary

Access to the

Workface

is

divided

into

three main Sections:

Section I:

Planning

for

Access. This

Section leads

the

reader through

the

considerations

to

be

taken into

account before

a

preferred access solution is identified:

the

legal framework,

assessing

the

risks and method

of

work, matching requirements with

the

capabilities

of

various types

of

access;

(5)

Summary

Section

II: Methods

of

Providing Access.

This Section takes

each

method

in

turn

and

gives an

introduction

to the

characteristics, typical uses and possible disadvantages

of

each;

Section III:

Checking

and

Maintaining Access.

This Section

is to

be

used when

a

preferred option has been identified,

to check

that the installation

is

satisfactory and

to assist in

carrying

out

periodic checks and inspections

while

the access

is

in

use.

The site

guide concludes

with

a

reference section, giving full

titles of the

documents referred

to

throughout

the

guide,

and

a

subject

index.

Temporary Access to the Workface

Construction Industry Research and Information Association Special Publication 121, London 1995.

First published 1995.

©

CIRIA 1995 ISBN

0860174220

Key Words Reader Interest Classification

temporary access, site engineers, Availability unrestricted scaffolding, site managers, Content advice/guidance access plant, site Supervisors, Status committee guided

safety, . client representatives, students. User construction professionals

Published by CIRIA, 6 Storey's Gate, Westminster, London SW1 P 3AU.

All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, including photocopying and

recording, without the written permission of the copyright holder, application

for which should be addressed to the publisher. Such written permission

must also be obtained before any part of this publication is stored in a

retrieval system of any nature.

(6)

Acknowledgements

CONCEPT

Temporary

Access to the

Workface

is

the output

from

CIRIA

Research Project RP498.

It is

one

of

the

series of

site

guides produced under CIRIA's Programme Advisory Committee

for

Construction Operations.

RESEARCH CONTRACTOR

This guide was

produced

by Sir

William Haicrow and

Partners

in

association with Laing

Civil

Engineering and Haicrow Fox.

Project Manager and Editor Ted Kay Halcrow Principal Author David Lloyd Laing Text and Diagrams Kit Yardley Laing Declan Mullins Laing

Graphic Design and Layout Trevor Good Halcrow Fox

The sections on abseiling are based on

a

draft by CAN Ltd and the sections on powered platforms are based on drafts by Tim Watson of EPL Plant and Access Hire.

COPYRIGHT

CIRIA

is

grateful

to the

following organisations for

permission

to

reproduce

their

material

in this

publication:

British Standards Institution. Leada Acrow Ltd.

Building Employers Confederation. National Association of

Construction Industry Training Board. Scaffolding Contractors.

GKN Kwikform Ltd. Scaffiag Ltd.

Health and Safety Executive. Thomas Telford Ltd. Complete copies of BS 5973: 1993 can be obtained by post from BSI Customer Services, 389 Chiswick High Road, London, W4 4AL, Telephone 0181 996 7000.

Health and Safety Executive material is reproduced with the permission

of the Controller of HMSO.

(7)

Acknowledgements

FINANCIAL CONTRIBUTIONS

The

research project was

funded by the

DoE Construction Sponsorship Directorate and CIRIA's

Core

Programme.

PROJECT STEERING GROUP

CIRIA, Haicrow and Laing

wish to

express their appreciation and thanks

to the

Project Steering Group which guided

the work

and made valuable contributions in

reviewing and agreeing

the

text.

The

group comprised:

J

D Bevan (Chairman) Tarmac Construction

P Donoghue Wimpey Engineering and Construction

I F Goldsby Balfour Beatty Civil Engineering Limited

S Hare G Maunsell and Partners

M James Health and Safety Executive

J

E Long National Association of Scaffolding Contractors

A

Maitra Health and Safety Executive

L Parker Trafalgar House Construction

R Wagstaff Galliford PLC

T

Watson International Powered Access Federation

CIRIAs Research Manager for the project was

0

W Churcher.

SOURCE MATERIALS

CIRIA

is

grateful

to the

following organisations whose guidance documents

were

used

for

reference during preparation

of

this

guide:

British Standards Institution. Industrial Roped Access Trade Building Employers Association.

Confederation. International Powered Access Construction Industry Federation.

Training Board. National Association of Scaffolding Construction Plant Hire Contractors.

Association. Prefabricated Aluminium Scaffolding Health and Safety Executive. Manufacturers Association.

(8)

Contents

Page No. INTRODUCTION

AND

SCOPE

SECTION I PLANNING FOR ACCESS

Introduction

1

1.1

Getting Started

2

1.2

Legislation

4

1.3

Risk Assessment

6 1.4

Work Operations

10 1.5

Environmental

and

Site Restrictions

14

1.6

Economics

18

1.7

Summary

of

Options

20

1.8

The Details

26

SECTION II METHODS

OF

PROVIDING TEMPORARY

ACCESS

Introduction

33 11.1

Access

to

Heights

11.1.1 Ladders

34

11.1.2 Scaffolds

40

11.1.3 Towers 61 11.1.4 Hoists

64

11.1.5 Mobile Elevating

Work

Platforms

66

11.1.6 Mast Climbing

Work

Platforms

70

11.1 .7 Man-riding Skips 72

11.2

Access

from

Heights

11.2.1 Suspended Access 74

(9)

Contents

Page No.

11.3

Special Requirements

11.3.1 Access

to

Below Ground 80

11.3.2 Access

over

Water 82

11.3.3 Confined Spaces 84

11.3.4 Segregation

of

Workers from

Machinery and Plant 86

11.3.5

Work

Adjacent

to

Roads

and Railways

87

11.4

Protection

Against

Falls

from

Heights

89

SECTION III CHECKING AND MAINTAINING ACCESS

Introduction

93

111.1

Checking Principles

111.1.1 Objectives

94

111.1.2

When

and

What to

Check

95

111.1.3

Who

should Check

96

111.1.4 Statutory Requirements

97

111.2

Checklists

111.2.1 Ladders, Steps and Trestles 100

111.2.2 Scaffolds 101 111.2.3 Towers 105 111.2.4 Passenger Hoists 107 111.2.5 MEWPs and MCWPs 109 111.2.6 Man-riding Skips 114 111.2.7 Suspended Access 115 111.2.8 Abseiling 118 111.2.9 ProtectiveEquipment 119 BIBLIOGRAPHY 120

SUBJECT

INDEX 124

(10)

Temporary Access

- Introduction

and Scope

It

is

vital

to the safe

and economic progress

of

construction

work

to

make

sure that

temporary access and working platforms are:

thoroughly planned;

properly constructed;

correctly used;

adequately maintained.

The very

nature

of

construction means

that the

workplace evolves and changes

as the

project progresses. Access arrangements

have

to

keep

abreast and ahead

of

this developing process, otherwise safety, productivity and

quality on site would quickly

deteriorate.

SAFETY

GOOD ACCESS

PRODUCTIVITY QUALITY

Almost 40% of

fatal and

major

injuries

to

construction employees

are

caused

by falls from

a

height.

It is

therefore obligatory that:

a

safe

route

to

and

from every

workplace is provided and maintained.

This can be by

ladders, staircases, gangways, hoists,

or other

means;

every

workplace is safe,

ie

working platforms

must be

large and strong enough

for

people to work, and

must

provide protection against accidental falls

of

people and materials.

(11)

Temporary Access

- Introduction

and Scope

Between

April

1989

and March

1993:

Around

4500 workers fell off

scaffolds,

of

whom

45 died

as

a

result

Around 350 scaffolds collapsed, injuring almost 120 people

Around 1000 people

were

seriously injured by

articles which

fell

off

scaffolds.

This

site guide

aims

to give

young professionals basic information

on the

different types

of

access

that

may be

encountered

on

a

construction site,

together

with reference

to the

legislation

and

authoritative documents which govern

their

use.

It is

mainly concerned with

access

for

personnel, rather

than for

plant, equipment and materials.

This booklet

is

not

intended

as

a

design

guide

— those involved

in the

detailed design

of

access arrangements will

need

to refer to the

relevant British Standards and

other

documentation listed

in

Section II.

The guide

is

split

into

three

parts:

Section

I discusses

the

parameters which need

to be

considered when planning

access arrangements and choosing equipment, and

lists the

access options available;

Section

II describes in some detail

the

various

forms of

access,

their

applications and limitations;

Section

III provides important information about

(12)

Temporary

Access - Introduction

and Scope

REFERENCES

Throughout

this

guide, references

to

relevant British Standards, Health and Safety Executive publications and

other

sources

of

useful information

are

given

at the

end of

each

topic.

A

full

bibliography

is

given

at the

back

of

the

guide.

The

references within

the

text

are

given

in

solid boxes

as

below:

REFERENCES

The titles in these

boxes may

appear in

shorthand form,

but the full titles can be

obtained

from the

bibliography.

KEY

Particular points

of

emphasis

are

marked with exclamation marks.

Situations where specific calculations are required

are

indicated by

the

calculator sign.

(13)

Planning For Access

INTRODUCTION

Access equipment

is

available

in

a

wide variety of

forms,

from simple

ladders

to

sophisticated mechanical platforms.

This

means

that

suitable access can be provided

for

every construction operation.

This

section

of the

handbook

offers advice on how to

assess

the

access requirements

for

a

construction project and

gives

guidance

on

choosing

the right type

of

access equipment.

Although primarily directed towards building and civil engineering

new

works,

the

advice

is

equally applicable to maintenance, refurbishment and demolition.

Part

Contents

1.1 Getting Started

1.2 Legislation

1.3

Risk

Assessment

1.4

Work

Operations

1.5 Environmental and

Site

Restrictions

1.6 Economics

1.7 Summary

of

Options

(14)

Planning For Access

-

Getting Started

The

planning

of a

project

is

an

iterative process which aims

to

optimise

safety and

efficiency during construction.

Time

and

care taken

at

the

planning

stage will

reap dividends later.

The

individual construction

tasks will be the primary

factor

in

determining

what

access arrangements

are

required,

but

statutory requirements,

site

restrictions, economics,

the

availability

of

equipment, and individual preferences and experience

will

all influence

the final

choice.

Access requirements should

be

determined logically

from

a

thorough

study

of

the work

operations required.

Do not decide on

a

scaffold

at

the

outset and

then

realise

part of the way

through

the

job

that

it

does not

really

suit the tasks in

hand.

Contractual relationships

on

a

site

influence

who

is

responsible

for

access arrangements.

The

responsibilities

must

be defined

clearly

at

the

outset and

all

parties must

be

aware

of

their

duties.

This guide is directed

at

access

for

personnel.

Access for

plant, equipment and materials must

also be

carefully considered

during the

planning process.

(15)

Planning For Access

-

Getting Started

1.1 BUDGET PROJECT DURATION WORK OPERATIONS SEE PART 1.4

'I,

LEGISLATION SEE PART 1.2 ECONOMICS SEE PART 1.6

1

RISK ASSESSMENT SEE PART 1.3 [ENVIRONMENTAL AND SITE RESTRICTIONS SEE PART 1.5

DETAILED ACCESS ARRANGEMENTS

SEE PART 1.8 AND SECTION II

+

Unsafe systems

of

work contribute

to almost

half of

(16)

1.2

Planning For

Access

-

Legislation

There are

various

statutory

requirements

which

apply when

assessing

the

requirements

for

access, and choosing

the

equipment needed.

THE

HEALTH

AND SAFETY AT WORK ETC.

ACT, 1974, places

a

particular

duty on

employers

to

ensure the

provision and maintenance

of safe

access

to

and

from

any place

of

work

under

the

employer's control.

Employees

are

required

to

report

any defects

and

must

not interfere

with, or

misuse, equipment supplied.

THE

CONSTRUCTION (WORKING PLACES)

REGULATIONS, 1966, require

that

a

safe route is provided

to

and

from every

workplace and

that every

workplace is

safe.

Furthermore,

these

Regulations

also

demand

that

the equipment used

for

access is:

suitable;

of

sufficient

quality for

its purpose;

in good

condition;

properly installed

and

maintained: (see footnote

on

page 5)

THE

CONSTRUCTION (DESIGN

AND

MANAGEMENT)

REGULATIONS, 1994, place duties

on

clients, designers, planning supervisors and contractors

to

focus

on

health

and safety

matters throughout

all

stages

of

a

construction

project

from

conception, design and planning through

to

the

execution

of

works

on site

and subsequent

maintenance, repair and demolition. Access requirements therefore

must be

considered

from the

outset and be included

in the safety

plan required by

these

regulations.

(17)

Planning For

Access

-

Legislation

1.2

THE

MANAGEMENT

OF

HEALTH

AND

SAFETY AT

WORK

REGULATIONS, 1992, require

that the

risks

associated with

any

work

activity are

assessed so

that the

necessary preventative and protective measures

can

be identified

and put in

place. Invariably

the

means of access which

will be

provided

to carry out the work

will have

to

be addressed.

THE

PROVISION

AND

USE

OF WORK

EQUIPMENT REGULATIONS, 1992, require

that

equipment:

U is

suitable

for

its

intended use;

takes working conditions and hazards

in

the workplace into account;

is properly maintained.

As well

as

these

overriding

pieces of

legislation which

apply

to

temporary access

in

general,

each

specific

type

of

access

equipment

also

has rules governing its manufacture and use. These

particular

statutory

requirements,

together

with

other

authoritative documents,

such as British Standards, HSE Guidance Notes, and

other

documents,

are

listed

in the

reference boxes which

may be

found throughout Section II

of this

guide.

There may

also be particular client or

company rules which apply

to particular

sites.

It is

everyone's

responsibility

to

ensure

that

regulations

are

followed.

If

see

something

that

is

wrong

then

make sure

that

something

is

done

about

it.

Footnote: The

legislation is

current

at

the time of

going to

(18)

1.3

Planning For

Access

-

Risk Assessment

Legislation requires

that

a

risk

assessment

is

carried

out

for

every work

operation involving significant risk.

Where

a

significant

risk

is

found to

exist,

then

measures must be

taken

to

remove

or

minimise

it

in the

following

order

of priority

a) remove

the

risk(s)

if

possible; then b) reduce

the

remaining risk(s);

then C) protect

the

maximum number

of

people against

the

risk(s);

then d) provide individual protection —

as

a

last resort.

Risk assessment should

not only

address

the

work

operation,

but also

consider where

it

is

carried

out, e.g.

at

height,

below

ground,

over

water. Risk assessments for

any

construction operation

will

therefore invariably involve addressing

the

means

of

access

to

carry out the

work.

Provision

of

a

properly planned and

well

maintained access platform

will fulfill the

obligation

to

"protect the maximum number

of

people"; provision

of

a

safety

harness

to an

individual worker can

only be

considered

as "a

last

resort" measure.

Choosing an inappropriate method

of

access

can,

in itself,

introduce

further

hazards

to

the

operation.

Very often

the

results

of

planning and carrying

out

risk assessments

for various

work elements

will

lead

to the

use

of

standard solutions

for

access, e.g. scaffold platforms with ladder access. In

these cases there are

Standards and Guidance Notes which specify

the

working details to

be

used and specific precautions, inspections and

maintenance

to

be put in

place (see Sections II and

Ill

of

(19)

Planning For Access

-

Risk Assessment

1.3

If, however,

an

unusual, innovative

or

unique access solution is

to

be adopted, then

a

full and

detailed risk assessment

for

the

means

of

access itself

must be

carried

out in order

to

be

satisfied

that the

design

is

adequate and

that

installation, maintenance, use and removal

of

the

equipment is carried

out

safely.

THE

DESIGNER'S ROLE

Designers

of

both permanent and temporary

works

are required

to

consider safety during

initial

construction and future maintenance, repair and demolition.

The

designer

can greatly assist

in this

by considering

the

following:

can prefabrication

be used to limit the

risks arising

from

working

at

heights?

can permanent access arrangements

be

detailed to permit

their early

construction?

can

slabs or

hardstandings

be detailed

to

suit

mobile access equipment?

are there any

potentially hazardous features

of

the

site or

permanent

works

which need bringing

to

the attention

of the

contractor?

can

permanent facilities

be

built-in

to

ease

access for maintenance

of the

structure over

its

life?

The

designer

is

in the

unique position

of being able to

remove

risks

at

the

design

stage

instead

of

leaving

the

contractor

to

manage difficult access problems

on

site.

HSC

Guide

-

Designing

for

health and

safety

in

construction

CIRIA

CDM

Regulations

-

case study

(20)

1.3

Planning For Access

-

Risk

Assessment

THE

SITE SUPERVISOR'S ROLE

Although

a

project

may be

thoroughly planned, variations

and

unforseen operations

will

inevitably

occur

during

construction.

This

is

when

many

accidents occur.

It

is

often

because

an

ad

hoc

access arrangement

is

used which is inappropriate.

REMOVING

THE

RISKS

Do

not

work at

heights

or

down holes

if it

can

be

avoided.

It is

potentially hazardous and usually

less

efficient than working

at

ground level.

Think

about prefabrication

Why

provide temporary access

if

permanent access is available?

Plan

the work so that

permanent access routes,

such as stairways, are constructed as work

progresses.

Over

half of the fatal injuries

to

workers

in

the

construction industry

are caused

by

falls

from

height.

These problems can

only be

addressed by:

regular re-assessment

of

access arrangements;

close

day-to-day supervision

of the work

by experienced supervisors;

training

operatives, particularly

to

recognise risks to themselves and others.

(21)

For Access

-

Risk

Assessment

1.3

The

construction and installation

of

temporary access

is

a potentially hazardous operation

in

itself.

Think about where

and

when

to install

the

temporary access equipment, e.g.

fix

ladders

and

platforms

to

structural

steelwork before

it

is

erected; add walkways and guardrails

to

bridge

beams

while they

are

on

the ground.

Materials, equipment and rubbish

on

access-ways and working platforms

are

obstructions and

may cause

people

to

trip.

Plan platforms

that are

large enough

for

the

operatives, plant

and

materials needed

to do

the

job.

Lack

of

knowledge is dangerous.

Make sure everybody

on site

knows about the

access arrangements

so that they

can carry out

their work

safely.

Use

the

information provided by access

equipment manufacturers

or

suppliers

(they

will

ofter

provide on-site

training

it

required).

A

good access platform:

reduces

the risk

to

those

working

on the

platform;

reduces

the risk

to

those

working

or

passing by

below;

improves

quality of

work;

(22)

1.4

Planning For Access

-

Work Operations

In

order

to

choose

the

correct access equipment, a

number

of

questions need

to be

answered regarding the

particular

work operations required — WHO, WHAT, WHERE, WHEN and HOW LONG? Consideration

of

these

questions

in turn will assist in

focusing

on the

options

which are

most

appropriate.

WHO

NEEDS ACCESS?

What trades

are going

to be

working

at the

various locations? Examples include steelfixers,

steel erectors, bricklayers, painters, joiners, masons, concrete gangs.

How many

people

are going to

need access and working positions

at any

one time?

Do

not

forget

about the

setting-out engineers and inspectors.

They

all need adequate access

and

working arrangements

to

carry out their jobs safely

and efficiently.

If

only one

or

two

people need access, then

a

ladder,

tower or

powered

work

platform could

be

considered —

a

hoist

or

complex scaffold

is

unlikely

to be the

best solution.

Where many

people need access, then

a

full

scaffold with ladder towers,

stair towers

or

a

hoist

will

probably be needed — powered

work

platforms

would not

cope.

(23)

Planning For Access

-

Work Operations

1.4

WHAT

WORK IS

REQUIRED?

This will

normally

be self

evident

from

the project drawings

and

works programme.

It

can now

be determined what materials

might

need

to

be stacked temporarily

on

working platforms

and

what space is needed

for

plant and equipment

to

carry

out the

various tasks.

If

large quantities

of

materials need

to be

stacked, then purpose designed loading

bays

or

towers could be incorporated

into the

access arrangements. WHERE

IS THE

WORK TO BE DONE?

At

ground level

or

3

storeys up?

In

an

excavation?

Over

water?

Is

it

intended

to

build

the job

in-situ

from

basic materials (bricks, reinforcing

bar

and

wet

concrete)

or will

large elements

be

prefabricated

in

a

factory

or on site

and lifted into place?

If

it

is

the

latter, then remember that access

will be

required

to connect the

elements together.

If

working

near

ground level, ladders

or towers

may suffice, whereas

at

greater heights

a

scaffold

or

powered work platforms

will be

required.

When access

built up from the

ground is difficult, then slung scaffolds

or

cradles could

be

considered or,

for

very difficult locations, abseiling techniques

might be

(24)

1.4

Planning For Access

-

Work Operations

WHEN

WILL THE WORK

BE DONE?

Can

a

particular

task be

scheduled

to

make

use of

permanent access arrangements

or

by adapting existing temporary access?

However, access equipment must

be

adapted

only

by authorised personnel.

Will

a

particular

order of

doing

the

work

make the

access needed

for

carrying

out

individual operations easier or

more

difficult?

When

working adjacent

to

or

over

railways

or

roads, can

some of the work be

carried

out during night or

weekend closures to

simplify

access arrangements? Example:

To reclad

a

building,

a

scaffold

will be

needed,

and it

will

have

to be tied

to

the

existing facade, which is

going to be

removed.

If

the

work

were

planned so

that

cladding commenced

from the

bottom, then ties

would have

to

be

removed and

it

would be

difficult

to

replace them without damaging

the new

facade. However,

if

the work were

planned

from the top

down, then

ties could be

removed and

would

not

have

to be

replaced,

as

long

as the

scaffold was dismantled

as

work progressed.

(25)

Planning

For Access

-

Work Operations

FOR

HOW

LONG

IS

ACCESS REQUIRED?

Is it

a

half

hour

task, such

as an

inspection,

or

a

week's work?

Will

continuous access be required

for

months?

Is

access likely

to be

required

again later in

the programme

for

following trades, inspections, testing or remedial works?

1.4

For

a

quick job,

a

tower, powered

work

platform

or

a

man-rider

from

a

crane might

be the way

to

approach

the

task. For activities lasting

for

weeks

at the same

location,

then

some

form

of

static

scaffold

would

probably

be

more appropriate.

Careful programming

and

intelligent supervision

of

the

works are

needed so

that

all

works in

a

particular

location

are

completed, inspected, snagged and approved

before

access and working platforms

are

removed.

Example:

To construct

a

reinforced concrete retaining wall, scaffolding working platforms with

ladder access

are

often

used

to

fix

reinforcement,

erect

formwork and place concrete.

The

scaffolding should

be kept in

place until

the

finished

wall has

been checked for defects, remedial

works have

been

carried

out,

formwork tie

holes

have

been

filled

and

joint

sealant has been applied.

(26)

1.5

Planning For

Access

-

Environmental

and

Site Restrictions

A

variety

of

restrictions have

to be

considered when planning

the day

to

day

operations required

on

a

project

and

choosing

the most

appropriate means

of

access to

carry out the

work.

Site

How much room is

there

between

the

new

Boundaries

works

and

the

boundary?

Is there

enough room

for

a

scaffold

or

a

hoist?

What

is

on

the other side

of

the

boundary and

will the

adjacent owner impose any

restrictions? Remember

that there

are particular

rules and

guidance

to be followed

if you

are

working next

to

railways, roads

or

water

(see

Parts

11.3.2 and 11.3.5

on

pages 82

and

87

of

this

guide).

Highways

Act

1971

Overhead

Are there any

power lines, telephone lines

or

Obstructions

overhanging

trees

that

may get in the

way of,

or cause

a

hazard

to, your

access arrangements?

Electricity

at

Work Regulations,

1989

Ground

Level

Look for water courses

(which

may

be liable

Obstructions

to

flooding).

Consider

the

presence

of

surface distribution mains

in

industrial plants.

Remember

that utility

companies require 24-hour access

to their

services,

so do

not obstruct access covers.

(27)

Planning For

Access

-

Environmental and Site Restrictions

15

Ground

Conditions

What

seems

a

dry site in

summer may become

wet

and boggy

in

winter.

This will

affect

the

movement

of

mobile platforms, and must

be taken into

account during

the

design

of

foundations

for

scaffolding and hoists.

Do not

forget what

may be just

underneath

the

ground, such as drainage pipes, cables, old basements

or

existing foundations.

Beware

of

poorly

backfilled excavations

and

do

not forget that

frozen

ground

can

give

a

false

sense

of

security.

Safety

of

the

Public

Are any

rights

of

way

to

be

maintained

across or

around

the

site? Will pavement gantries

be

required

to

allow safe

pedestrian access under

any

external scaffolding?

Consider the

need

for

warning

signs and

lights.

Site security

must be

such that members of

the

public, especially children,

cannot

gain

access onto scaffolds etc.

HSE

Guidance Note

GS7

On average,

one

member

of

the public is

killed

every

fortnight

through construction

(28)

1.5

Planning For

Access

-

Environmental and Site Restrictions

Weather

Is

it

an

exposed, windy site?

If

so, extra

Conditions

precautions

will

be

needed

to

stabilise

access

arrangements. Conditions on

exposed

sites

may

also limit the

use

that

can

be

made

of

powered platforms.

Do

particular operations need additional

protection

from the

weather?

Will

access

scaffolds

need

to be fully

sheeted?

Other

Will

particular access arrangements

for

one

Operations

operation cause problems with

other work

on

the

site? Perimeter scaffolds

are

likely to

need specially designed bridging

at

lower levels

to

allow

access

for plant and

materials. Consider

the

possibility

of

damage

to

access equipment

from

plant, such

as

cranes, dumpers, forklifts etc.

Working

Is all

work

to

be

done in

daylight?

If

not,

Hours

access-ways

and

working platforms

will

need

to

be

lit.

Fire

In some

locations flammable materials may

Precautions

not be

permitted

in

access equipment, e.g.

within occupied buildings and when carrying

out work on

underground railway systems.

The Loss

Prevention Council: Fire

code

of

practice

Fire

prevention on construction sites.

(29)

Planning For

Access

-

1.5

Environmental and Site Restrictions

Confined

When

working inside

a

structure,

or

any Spaces

other

confined space,

the exhaust

fumes

from

engines

on

powered work platforms

must be

properly vented (See

Part

11.3.3 on page 84).

(30)

1.6

Planning For

Access

-

Economics

If

alternative means

of

access are

equally suitable, practical, structurally sound and readily available,

the

final

arbiter will be

cost.

Estimating

the total cost

of

the various

options entails calculating

the

elements

of

labour, plant and materials

for

the

period

of time the

access

will

be required.

Example:

Compare

the costs

of

using

either

mobile powered platforms

or

scaffold platforms

with ladder

access.

Powered platform

Hire of equipment £ p.w x weeks =

Fuel £ p.w x weeks =

Operator(s) £ p.h x manhours = Maintenance £ p.h x manhours = Allowance for back-up equipment £ p.w x weeks = Total cost of powered platform £ Scaffold

Hire of equipment £ p.w x weeks Labour — erect £ p.h x manhours Labour —

maintenance £ p.h x manhours Labour — dismantle,

move & re-erect £ p.h x manhours Allowance for loss of equipment (e.g. scaffold fittings)

(31)

Planning For Access

-

Economics

1.6

Adjustments

may

then have

to

be

made

to these

figures

to

account

for any

difference

in the

efficiency

of

either method.

This will

entail adding

or

deducting

a

figure

to

allow

for

differences

in

programme

time (site

overhead costs)

or

manhours

to

carry

out the

project works.

Access

costs are notoriously difficult to

estimate

during

the planning

stage.

For

a

comparative

cost

analysis

to be valid it

is

extremely important

to

ensure

that the

access requirements have

been properly understood. Otherwise

the

hire rates,

manhours and

time

periods

may be

inaccurate.

There

can

even be

differences

in

economics between

types

of

scaffolding.

Cost only

becomes

an

arbiter when

suitability has

been established.

Example:

Traditional

tube

and fitting scaffolding

is

relatively cheap

to

hire

but

is

slow

to

erect.

It

is

therefore better suited

to

longer durations

of

use.

Prefabricated proprietary system scaffolds

are

more expensive

to

hire

but are

quicker

to

erect.

They

may therefore

be better

suited

to

short

duration work.

(32)

1.7

Planning For

Access

-

Summary

of

Options

U)

z

0

C) -J 0. 0.

4

-J

4

C)

0

>-

I-

U)

z

0

-J LU

4

0. Ui LU U)

LADDERS

LADDER

TOWERS

STAIR

TOWERS

access and inspection

access

between working platforms

at

various

levels

used in

place of

ladder

towers where movement of

large

numbers

of

operatives is required ladder length generally

for

access only

user cannot

carry

tools and materials

needs a

suitable footing

user cannot

carry tools

and materials available space

at

greater heights

a

hoist

may be

more efticient 34 38 39

(33)

Planning For

Access

-

Summary

of

Options

1.7

INDEPENDENT

TIED

SCAFFOLD

PUTLOG

SCAFFOLD

BIRDCAGE

SCAFFOLD

provides good working platforms

for

a

variety

of

work

very

adaptable brick laying re-pointing access and working platforms below ceilings and

soff

its M&E installation available space restricts access

at

ground level relies

on

the structure

for

its stability

available space restricts access

at

ground level

relies

on the

structure

for

its

support

restricts access

in the

space below

(34)

1.7

Planning For Access

-

Summary

of

Options

w a- ILl w Cl)

TOWER

HOISTS

SCAFFOLDS

where an independent scaffold cannot

be

erected from ground level M&E installation inspections

short

duration

work in

many locations

fast

access

to

high

levels need specific design potentially hazardous

to

erect, inspect

and

dismantle

need level, firm foundation height restricted by base dimensions available space need trained operators "fixed" location need

to

be

tied

in to

structure

TRUSS-OUT

AND

CANTILEVER

SCAFFOLDS

C')

z

0

C-) -J a. a. -J C.)

0

>-

I-

U)

z

0

-J

46,

47 61 64

(35)

Planning For

Access

-

Summary

of

Options

1.7

M&E installation steelwork connections, finishings, maintenance, inspections, repetitious work

at

different levels

in

one location cladding maintenance

short

duration work

at

high

level

or

below ground inspections, maintenance, steelwork connections, ground conditions limit

of

reach loading restricted need trained operators need trained operators need suitable ground conditions

may need tying

in at

heights need specific

type

of

crane 66 70 72

MOBILE

ELEVATING

WORK

PLATFORMS

MAST

CLIMBING

WORK

PLATFORMS

MAN

RIDING SKIPS

U)

z

0

0

-J 0. 0.

1

C.) 0. >-

I-

U)

z

0

-J LU

4

0. LU Iii Cl)

(36)

1.7

Planning For

Access

-

Summary

of

Options

U)

z

0

C.) -J 0. 0.

-j

C.) 0. >-

I-

CRADLES AND

BOSUN'S

CHAIRS

SLUNG

SCAFFOLDS

ABSEILING

4,.

high level work

on

ceilings and soffits work above railways, roads

or

operating factories painting, inspection, maintenance sometimes used

in

conjunction

with

abseiling techniques difficult locations

short term

light work inspection, maintenance, geotechnics limited safe working load . attachment points

..

need specific design . potentially hazardous to erect, inspect and dismantle

limited

safe working load .

need

trained operators . restricted work area needs highly skilled and trained operatives restricted work area 74

75,

76 78 U)

z

0

-J Ui

4

0. Ui Ui U)

(37)

Planning For Access

-

1.7

Summary

of

Options

Within

the

broad groupings

of

access options given

on the

preceding pages

there

is a

wide variety of

equipment available

from

different suppliers and manufacturers.

For

example, access scaffolding can

be

erected using

traditional tube

and

fittings

or

with

a

variety

of proprietary systems.

Individual items

of

equipment may have particular technical advantages

or

disadvantages

for

a

particular application

or the

choice may be

simply

a

question of economics and availability.

Suitability first, cost

second.

There are

options

for

access

other

than

the

broad groupings

shown in this

guide.

Great care must

be exercised when using them and detailed planning must

be

carried out. Examples are:

other

items

of

temporary

works

such

as

formwork

or

falsework;

incomplete sections

of the

permanent

works

used

(38)

1.8

Planning For

Access

-

The Details

Having

decided what

access equipment

is

required

for

the project,

the

next

stage

is to

design and detail the

equipment

to

suit the exact

requirements

of

the

job.

Users

of

access equipment

must feel that

it

is

safe

but

should

still

be

alert

to

the

dangers of

a construction

site.

Who will carry out the

design

and

detailing

that

is required?

It

could be:

the site

engineer

(if

deemed sufficiently qualified and experienced

by senior

personnel);

the

contractor's temporary

works

design department;

the

equipment supplier;

a

a

specialist subcontractor;

a

design consultant.

The choice will

depend

on the

extent,

scale

and complexity

of

the

design

work

required and

also

on

who

is

supplying

the

equipment.

The

person

who

carries

out the

design and detailing

will

need

a

good

brief so that the

access arrangements

will

satisfy the

requirements.

As well as

outlining

what

is required,

the

brief should include:

a

general and

particular

loading requirements (men

and

materials);

site

limitations;

information

on

ground conditions;

a

environmental parameters (e.g. wind and water);

the

period

the

access

will

be

in

use;

location.

(39)

Average Scaffold Fitting

Access-

1.8

The Details

3.9m Scaffold Board 6.4m Scaffold Tube

Spot

Board and Mortar Barrow

of

Mortar! Concrete 100 Bricks Bundle

of

Reinforcement 1m3

of

Stone

or

Concrete U—

24kg

28kg

275

kg 2000 kg

2400

kg

Planning For

TYPICAL

LOADS

V

1.5kg

Operative

Operative

plus

Tools

30kg

80kg

90kg

(40)

1,8

Planning For Access

-

The Details

Particular tasks, which need

to be

undertaken during

the

design and detailing phase,

are as

follows:

Ladders,

Ladder

Towers,

Stair Towers

For simple ladders

it

is

a

question

of

following

the

rules and guidance (see Section

Il),

and making

sure that

a

firm

foundation exists and

that the ladder can be kept

stable

during

use.

Ladder

towers

and

Stair towers

need

to

be specifically designed and detailed

to

suit the

job

requirements.

Scaffolds

In

principle all scaffolds,

whether tube

and fitting

or

proprietary systems, must be designed. In practice, standard approaches can

be

adopted

for

many

situations provided

that the

rules regarding

layout and

loading contained

in

BS

5973

are followed.

However,

a

full

design

and

design

check by

a qualified scaffold

designer

is required for sheeted scaffolds, unsheeted scaffolds over

50

metres high, loading towers and

all

special scaffolds (e.g. truss-outs and cantilevers).

Additionally an assessment

must be

made

of

the

ground conditions

below the

scaffold footings so

that

suitable foundations

may

be

detailed.

An

assessment

must also be

made

of

suitable anchorage

positions

for

ties.

(41)

Planning For

Access

-

1.8

The Details

Scaffolds

are

classified

by type according to

their

use. Each

scaffold has a set

maximum loading,

which

determines

the

maximum

bay

centres as

follows:-

Use of Scaffold Type of Scaffold Number of boards (centres of standards) Maximum number of working platforms* Typical load

_—

examples pej..— bay Maximum ...— bay length Platform loadings kg/rn2 Inspection Painting Light access Very light duty Independent 3 j (0.77m) 1 No materials 1 operative LI plus tools 2.7m 75 Inspection Painting Cleaning Light duty Birdcage Fully boarded 1 No materials 1 operative LI 'LI plus tools 2.5m x 1.2m 75 Plastering Painting Cleaning Light duty Independent 4

i

Om) 2 2 operatives plus 175 kg materials 2.4m 150 Building work Light brickwork General purpose Independent 5 (1 .2m) 2 pIus 1 very light duty 1 operative

,

plus 350 kg materials 21m 200 Brickwork Heavy cladding Heavy duty Independent 5 (1 .2m) 2 plus 1 very light duty 2 operatives plus 250 kg materials 2.Om 250 Masonry work Concrete Blockwork Special or Masonry Independent 6 (1.45m) 1 plus 1 very light duty 2 operatives plus 400 kg materials 1.8m 300 New Brickwork Putlog Scaffold 5 (1.2m) 1 1 operative pIus j 140

'

bricks 2.Om 250 * on whole scaffold

(42)

1.8

Scaffold

Towers

Hoists

MEWPs

and

MCWPs

Planning For

Access

-

The Details

Proprietary prefabricated towers

will have

a

set

of

rules which must

be

obeyed.

Towers manufactured

from tube

and fittings

must be

specifically designed

for the

task.

With either type it

is

extremely important

to

make

sure

that they are

mounted

on

a

stable, level foundation.

The

hoist manufacturer

will supply

details

of

the

installation requirements.

The

user

will

have

to

arrange

the

design and detailing

of

suitable foundations and

tying-in

arrangements.

For

powered platforms

it

is necessary to assess

the

ground conditions and provide

adequate foundations

for

the

outrigger loads.

Mobile Elevating Work Platform

and

Mast Climbing Work Platform

are

usually abbreviated

to

MEWP and MCWP respectively.

(43)

Planning For

Access

-

1.8

The Details

Slung

These must always be

designed

by

a

Scaffolds

qualified

designer

and

a

design check

carried

out.

An

assessment

must also be made of the

anchorage points including load testing where applicable.

Cradles &

Anchorage points must

be

assessed and

Bosun's

Chairs

tested.

Calculations

are

needed

to

determine the requirements

for

outriggers and

counterweights.

The

specialist subcontractor

will

be required

to

prepare

a

full

method statement detailing

the safe

system

of

work. Suitable anchorage points

will

need

to

be

located and assessed.

All

members

of the site

team

(staff

and

operatives)

must

be made aware

of

access

arrangements

including any

limitations

of

use.

Abseiling

Having

spent all this time and

trouble

in

carefully planning and designing

the

access arrangements, make sure

they are put

into place

and

used properly.

(44)

Page

blank

(45)

Methods

of

Providing

Temporary Access

U

INTRODUCTION

Many different

kinds

of

access equipment

are

available. In

the

first

parts

of this

Section

the most

common forms

are

described and features

of their safe

installation and use

are

given.

The

methods

of

access described are:

Part

Contents

11.1

Access

to

Heights

11.1.1 Ladders 11.1.2 Scaffolds 11.1.3 Towers 11.1.4 Hoists

11.1 .5 Mobile Elevating

Work

Platforms

(MEWPs)

11.1 .6 Mast Climbing

Work

Platforms

(MCWP5)

11.1.7 Man-riding Skips

11.2

Access from

Heights

11.2.1 Suspended Access

11.2.2 Abseiling

The last two

parts

of this

Section

give

information

on

the particular access requirements

and

safety considerations

for

various circumstances.

11.3

Special Requirements

11.3.1 Access

to

Below Ground 11.3.2 Access

over

Water

11.3.3 Confined Spaces

11.3.4 Segregation

of

Workers from Machinery and Plant

11.3.5

Work

Adjacent

to

Roads and Railways 11.4

Protection

Against

Falls

from

Heights

(46)

11.1.1

Access

to

Heights

-

Ladders

LADDERS

Ladders should

be

used primarily as

a

means

of

access, NOT as

a

working platform.

Ladders used for access must

be secured. Alternative restraint near base

if

not

possible at top.

Found on firm level ground.

Support both stiles evenly. Heel stiles in where possible.

Types

of

Ladder

Construction: timber or aluminium alloy

Standing ladder: single step- ladder. Uses separate structure for

support. Up to 6m long

Pole ladder: variant of above with

stiles made of halved Whitewood poles. Up to 1 Om long.

Extending ladder: consists of 2 or

3 sections coupled together and extended by sliding over or inside each other. Up to 1 7m. (Not preferred for construction work.) Step-ladder: freestanding ladder with rectangular treads. Several types.

Roof ladder: runged ladder with integral hook at top end which secures over roof ridge.

Detail Extra support may be required to reduce swaying and bending. Support stiles only, not rungs. Foothold not to be obscured.

wire tie rod may be every rung

(always beneath rung)

Alternative restraint to base of ladder using stakes

References

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