Heating & Ventilation, Air Conditioning & Refrigeration: Chapter 1

Heating and Ventilation, Air Conditioning and RefrigerationCore training materials

chapter1

ii

Introduction iii

Acknowledgements iv

Chapter1 TheMESSector,organisation,basicsafety

andcommunications 1

Chapter2 Identifythephysicalforcesthathaveanimpact

ontheMESsector 35

Chapter3 Interpretdrawings,specificationsanddata,

anddescribetheuseofITinthesector 65

Chapter4 Toolsandtheworkprocessesusedinthe

MESsector 79

Chapter5 Calculateandquantifyfromdrawingsand

markandsetout 115

Chapter6 Understandingbuildingconstructionmethods

andthematerialsusedintheMESsector 133

Multiplechoicequestions 149

Mappinggrids 152

Index 154

Contents

The early idea for this resource came from research carried out by SummitSkills aimed at reviewing the training and assessment support materials for each industry within the building services engineering sector.

The initial results highlighted gaps in the available common training materials for the heating and ventilating and refrigeration and air conditioning industries.

Following the initial research, a further feasibility study was carried out in partnership with the delivery network to ascertain the specific requirements of new supporting training materials.

SummitSkills commissioned Harcourt Education Ltd to produce this resource, which is designed to provide support materials for learners undertaking core studies within the heating and ventilating and refrigeration and air conditioning qualifications.

Introduction

iii

iv

HeatingandVentilation,AirConditioningandRefrigeration

Acknowledgments

SummitSkills would like to express its appreciation to the Harcourt publishing staff for producing such a high quality product.

We also give special notice to the commitment, support and work of technical author John Hollis in producing the technical content of this resource.

We would also like to thank Mike Carman, John Wilcock and Jane Gartshore for their contribution to the development and conclusion of this project.

SummitSkills trusts that the user will find this resource a valuable aid to their studies within the heating and ventilating, and refrigeration and air conditioning industries.

Neil Collishaw and Michael Reeves

Development Managers SummitSkills

The publishers would like to thank the following for their kind permission in reproducing photographs:

Alamy Images – 22 (scissor)

Construction Photography – 22 (boom)

Getty Images – page 29

Harcourt Education Ltd/Gareth Boden – page 20, 35, 65, 79, 93, 103, 104, 105, 110, 112, 113, 117

Harcourt Education Ltd/Ginny Stroud-Lewis – page 15, 16

Harcourt Education Ltd/Jules Selmes – page 12

Keith Arrell/JTL – page 1

Every effort has been made to contact copyright holders of material reproduced in this book. Any omissions will be rectified in subsequent printings if notice is given to the publishers.

All rights reserved. The material in this publication is copyright. Pupil sheets may be freely photocopied for classroom use in the training institution. However, this material is copyright and under no circumstances may copies be offered for sale. If you wish to use the material in any way other than that specified you must apply in writing to the publishers.

OVERVIEW This chapter is an introduction to the MES industry and at the end of this section you should be able to:

• describe the structure of the MES sector

• list the main services/trades within the industry

• list the parties that are responsible for agreements within the sector

• describe the career paths and progression routes available

• list the main Acts and Regulations that govern health and safety in the workplace

• list the general rules that apply to safe working practices

• describe the value of good communications and personal presentation.

The MES Sector organisation, basic safety and communications

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chapter1

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Heating and Ventilation, Air Conditioning and Refrigeration

An overview of the MES sector

What are Mechanical Engineering Services (MES)?Most people understand the job of a plumber because, at some time or other, a plumber has turned up at our homes to deal with hot and cold water system problems, to work on the central heating or install waste water pipework. The activity normally relates to where people live, or smaller commercial premises like small hotels or rest homes.

If you consider larger commercial and industrial premises and the mechanical services that are in them, then there is a need here for specialist installers and maintenance engineers with a mixture of skills, including plumbing, mechanical engineering and electrical work. Initially many of these are related to heating and ventilating. The term ‘H&V’ is still loosely used by many when referring to this sector. However, other specialist areas have been added, such as refrigeration and air conditioning (RAC). Hence, collectively, the sector is now known as Mechanical Engineering Services (MES).

The main MES trades and job titles are listed in Table 1.01.

MES sector trades Job titles

Domestic Installer / fitter

Industrial / commercialHeating fitter / pipe fitter / pipe fitter welder

Duct work Installer / erector

Service and maintenance Engineer

Refrigeration and air conditioning Engineer

Table �.0� MES trades and job titles

Joining the MES sectorThe entry level for a school leaver would be at the trainee operative level, as an apprentice, and will follow the route that serves him or her the best. With good GCSE grades to start with, the opportunities for advancement are more open. It should be noted that the national training scheme allows for entry levels at any point during a working life. Therefore a mature person with interests, experiences and abilities should be able to gain entry to the sector via National Vocational Qualifications (S/NVQs). S/NVQs are about collecting evidence of what you know and what you can do and, as a trainee, there is an element of guided learning involved.

Did you know?

The main sector trade association is called the Heating and Ventilating Contractor Association (HVCA), covered later

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Chapter � The MES Sector organisation, basic safety and communications

Occupational Roles Relevant Qualifications NQF Level

Director Owner/Proprietor

Doctorate/MPil/Masters Higher Hons/Hons Degree Bachelors Degree/Certificate

5

Management Project Development MES Engineer Technician

BSE Technology and Project Management NVQManagement N/SVQs Site Management N/SVQs Design S&M Management Business Development

4

Supervisor/Team Leader Specialist Craftsman Operative/Technician

BSE Technology and Project Management NVQInformation Technology N/SVQ Health and Safety Certs Technical Certificate (England only)

3

MES Operative Craftsperson

HV ACR Apprenticeship – S/NVQ Health and Safety Certs Technical Certificate (England only)

2

Trainee OperativePre Level � Courses Health and Safety

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On the Job: Qualifications Paul left school with good GCSEs. He joined a refrigeration contractor as an apprentice and completed Level � and � NVQs after four years. During his training he spent a year working with a team installing equipment and two years working on service and maintenance. He also spent a few months working in the office and in the stores to gain an all-round knowledge of the company. He now commissions supermarket central plant systems that provide all the cooling for display cabinets on the shop floor, preparation areas and cold rooms. His experience of installation and servicing, coupled with his methodical approach to the work, provide him with the skills and knowledge to commission equipment so that it works reliably and efficiently.

Figure �.0� MES sector progression routes

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On the Job: Further trainingDanny started his working life in the agricultural industry for two years but realised that, although he liked the job, he felt that he could do better for his family. He had a problem with dyslexia but, by working hard and after receiving the right amount of support from his trainers, he overcame the problem and completed NVQ Levels � and � in ‘industrial/commercial installation’. His employer was so impressed with him that he was offered the chance to study for an NC in ‘Building engineering studies’. Currently Danny is a junior project engineer and is supervising some substantial MES projects and getting the rewards for all his hard work.

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Principal organisations within the sectorThe sector has several organisations that seek to monitor and influence what the industry does. A selection:

Heating and Ventilating Contractor Association (HVCA)

AMICUS

SummitSkills

Air Conditioning and Refrigeration Industry Board (ACRIB)

Awarding bodies

Heating and Ventilating Contractor Association (HVCA)HVCA is a trade association and employers’ organisation which aims to improve the commercial environment and professional standards throughout the industry and maintain a skills pool that meets the needs of the industry.

AMICUSThis is the national union for those who work in the MES sector. Through a network of shop stewards, safety representatives, officers and members, it campaigns for the building of a better future for the UK construction industry. Included in its goals for all workers are:

national collective agreements on wages and conditions

direct employment

holiday pay

protection and recognition of skills

the right to decent welfare, PPE and a safe working environment

pensions.

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Heating and Ventilating Contractors’ Association

Esca House 34 Palace Court London W2 4JG

Tel: 020 7313 4900

Fax: 020 7727 9268

e-mail: [email protected]

website: www.hvca.org.uk

Figure �.0� HVCA logo and address details

HVCA

Figure �.0� AMICUS logo


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SummitSkillsIt is the Sector Skills Council that looks after the training and development needs of the sector, as well as the National Standards used for S/NVQs. The board of SummitSkills is made up of employer representatives and associations from industry, and also trade unions. Its function is to provide direction for those involved with training and certification of employees within the electrical, refrigeration and air conditioning, plumbing, heating and ventilating industries.

Air Conditioning and Refrigeration Industry Board (ACRIB) ACRIB provides a central forum for all sectors and interests which fall within, or are served by, the air conditioning and refrigeration industry.

Its member organisations represent manufacturers, distributors, contractors, consulting engineers, specifiers, end users, training providers, researchers and others with a direct interest in the environmentally friendly and cost-effective provision and use of refrigeration, air conditioning and mechanical ventilation equipment.

It holds a voluntary register of operatives who have completed a refrigerant handling qualification.

Project management team organisationMany different people are involved with the installation and maintenance of the services in buildings. It goes without saying that the larger the contract, the more people will be involved. The principal individuals in a project team are likely to include those shown in Table 1.02.


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Individual Roles

Client the person or organisation that wants the work done and is paying for itspecifies the purpose of the buildingusually has an idea as to basic design of the building.

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Architect designs the building to meet the needs of the clientdesigns the appearance and construction of the buildingadvises the clientfor small projects, could produce all of the details.

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Consulting engineer acts on behalf of the architect specialist for specific services, such as structural, concrete, mechanical or electrical servicesmanages and acts as a resource for the installerusually produces the services’ drawing for a project.

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Quantity surveyor responsible for making up ‘bills of quantities’ for a projectmonitors the work in progress and quantities of materials usedprocesses claims for payment from contractors.

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Clerk of works checks the quality of materials usedchecks the quality of workmanship of finished workprotects the client’s interests by ensuring conformity to standards etc.verifies any tests performed.

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Table �.0� Project management team organisation

Some other appointments, which may be referred to during a project, are listed in Table 1.03.

Appointment Roles

Main contractor usually a building company, as these have the bulk of the work to carry outhas the contract for the whole projectresponsible for paying and coordinating subcontractors.

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Nominated subcontractor

named specifically by the client to carry out certain workmust be used by the main contractorMES companies are usually subcontractors.

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Non-nominated subcontractor

subcontractors chosen by the main contractortheir contract will be with the main contractor.

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Nominated supplier supplier of equipment and products appointed by the client, so must be used.

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Table �.0� Contractual appointments


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There may be further personnel on site during construction, as listed in Table 1.04. Some job titles may differ with different parts of the sector.

Job title Roles

Contracts manager overall responsibility for the viability of the project.•

Contracts engineer manages the day-to-day running of a contractresponsible for labour levels and organising materials.

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Site supervisor manages engineers on siteorganises who does what on siteensures that materials are available when requiredlooks after any amendments to agreed plansliaises with other trades to ensure a smooth running project.

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Operatives Engineers and apprentices who carry out the work, comprising: pipe fitters, fitter welders, RAC engineers, heating installers, assistants and labourers.

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Table �.0� Further on site appointments

Once a building has been constructed and officially ‘handed over’ to the client then another team takes on the management of its services. The staff, which could make up the service and maintenance teams, are shown in Table 1.05.

Job title Roles

Maintenance manager

usually resident on siteresponsible for keeping the building in operationorganises subcontractors and resident service teamscarries out risk assessments and issues ‘permits to work’monitors the condition of all plant on siteensures that legal requirements are met.

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Service manager may be resident on or off siteorganises teams of mobile service engineersmonitors the quality of service providedensures that service contracts are fully met.

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Table �.0� Service and maintenance management after construction


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Management of health and safetyHealth and safety (H&S) forms a very important part of everyday working life and you should be aware of your responsibility for the health and safety of yourself and others.

There are a number of legal requirements that must be met by employees and employers. These have been put in place to keep everyone involved within the sector safe and free from accidents. The law affects everyone, including:

the service engineer, who may be a temporary visitor to a place of work or a full-time resident on a site such as a hospital complex

installers working exclusively on construction sites or on the refurbishment of existing buildings

domestic installers working in a private home.

There are specific rules and laws for each of these, together with general health and safety rules and laws that affect everyone.

The two main bodies that establish and implement general health and safety laws are:

The Health and Safety Commission (HSC)

The Health and Safety Executive (HSE)

These two bodies formulate sets of rules that apply to specific places of work. Many of these are enshrined in statutes, laid down in Acts of Parliament. The main Acts and Regulations that apply to MES operations are:

Health and Safety at Work Act 1974 (HASAWA)

Workplace Regulations 1992

Construction (Design and Management) Regulations 2007

Construction (Health, Safety and Welfare) Regulations 1996

Manual Handling Operations Regulations 1992

Fire Precautions Act 1971

Electricity at Work Regulations 1989

Control of Substances Hazardous to Health (COSHH) Regulations 2002

Periodically these Acts and Regulations are revised and updated and new ones added. For instance, the recently introduced ‘F Gas Regulation, a European regulation aimed at the reduction of emissions of refrigerant gases to the atmosphere, will have a direct impact on those working in the RAC area.

During this section, you will learn more about these Acts and Regulations, which are designed to keep us safe at work. It is not intended to be an exhaustive review of the subject but more of an introduction. An operative should receive constant training on the application of H&S in the workplace throughout his or her time in the industry.

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We will look at this in more detail later in the chapter, divided into two working environments, occupied buildings and construction sites, but first we will look in more detail at the HASAWA.

Health and Safety at Work Act 1974 (HASAWA)In general, the rules that govern our own and our employer’s H&S responsibilities come directly from the Health and Safety at Work Act 1974. Under the HASAWA we, as employees, can be prosecuted for breaking the safety laws, as well as employers. We are legally bound to cooperate with our employer to ensure that our company complies with the requirements of the Act.

The HASAWA requires an employer to ensure, as far as reasonably practicable, our health and safety at work. The employer’s duty extends to:

provision and maintenance of plant and systems of work that are safe and without risk

safety in the use, handling, storage and transportation of articles and substances

provision of information, instruction, training and supervision as necessary to ensure the health and safety at work of employees

provision of access to, and exit from, the workplace that is safe and without risk

provision of adequate facilities and arrangements for welfare at work.

The main responsibility of individuals under the Act are:

to take reasonable care at work of our own H&S and that of others who may be affected by what we do

not intentionally or recklessly to interfere with, or misuse, anything provided for our H&S

cooperate with our employer on H&S matters, assisting our employer in meeting their statuary obligations

bring to our employer’s attention any situation we think presents a serious and imminent danger

bring to our employer’s attention any weakness we might witness in their H&S arrangements.

The Act refers to ‘places of work’, generally taken to mean factories, building sites, shops, offices and such like. However, if the work is taking place in an occupied domestic house, the Act still applies and the contractor becomes responsible for the owners’ or occupiers’ health, safety and welfare whilst the work is being done.

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Working in occupied premisesThe Regulations stipulate how the Acts can be implemented in a sensible way and cover the subjects of:

working environment

safety

facilities.

A contractor working in an occupied building has the responsibility to safeguard the regular users of the building and meet the requirements of the Acts. Some things that are deemed necessary are discussed below.

Maintaining the working environment This covers subjects such as workplace ventilation, temperature, the provision of adequate lighting, provision of adequate working space etc. The contractor is responsible for maintaining what is already in place before any further work is carried out.

Observing safety rulesThis covers all of the measures that need to be adopted to ensure a safe place of work, such as protection from falling objects, people falling from heights and protection from defective walking surfaces.

Provision of welfare facilitiesThese are the rules that stipulate the correct provision of toilet facilities, washing and the provision of drinking water.

Maintenance of personal hygiene It is in your own interest to keep yourself as hygienic as possible while at work, which may be difficult at times because of the nature of the work. However, some points to remember are:

Wear PPE that is applicable to the environment. For example, heavy safety boots may be suitable for a construction site but not desirable for an office or home. Hard hats are not always required, and overalls can be replaced with trousers and top when doing light work or servicing. However, keep all work wear as clean as possible and wash it regularly.

Wash hands thoroughly after visiting the toilet.

Wash hands thoroughly before contact with food.

Avoid washing with solvents or abrasive substances.

Use barrier cream before starting a job.

Use protective gloves whenever possible.

Wear personal identification when required; it is a must in some locations.

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Observe risk assessment requirements with respect to the protection required when dealing with dust and contaminants, for example when replacing air conditioning filters.

Prevention of accidents The best way to reduce the risk of accidents is to try to remove the cause. Methods of work should be assessed for risks, and a plan put in place to reduce them. A record of these ‘risk assessments’ is kept at the office or, in some cases, on site.

The rudiments of workplace safety, which you will first encounter and be required to follow, are:

Observe access and egress routes. Access to equipment or areas must only be gained by approval of the relevant management. Each site should have an access and egress route clearly defined, which will be away from vehicular routes and should be observed at all times. In factories, walkways and hazard zones should be clearly marked out.

Define a work area. A barrier may be required around your work area.

Place clean dustsheets over equipment and/or remove sensitive equipment.

Post safety signage so that others are warned of any potential dangers.

Use of confined space procedures. Occasionally we have to work in places that are deemed as confined spaces. This is normally where access and egress is difficult or where there is the possibility of hazardous or poisonous gases present. The requirements are such that a confined space procedure must be drawn up that will stipulate the procedures that must be followed. Do not enter confined spaces until you have been trained to do so. This dangerous area of work activity is controlled by the issue of ‘permits to work’, which should never be ignored or by passed.

Carry out effective electrical and mechanical isolation.Effective electrical or mechanical isolation entails: first correctly identifying the selected supply, isolating by turning off at a suitable isolation point, locking off and/or posting a sign, then verifying that the service is dead. These simple measures will prevent an accident.

Control dangerous substancesDangerous substances should be evaluated and controlled by reference to the recommendations of the Control of Substances Hazardous to Health (COSHH) Regulations 2002. These specify how products are to be used, stored and disposed of. Every place of work should have a glossary of COSHH data sheets for all of the substances used. Get to know them. Refrigerant gases and liquids come under the heading of dangerous substances, so it is essential that those carrying out charging, recovery or any other operation that may require refrigerant handling are properly trained and qualified to do so.

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Figure �.0� Device locked off with a padlock

Definition

Access is the way of getting into a work area and egress is the way of getting out


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Protect moving machineryRotating machinery, such as fans and motors, should be adequately protected with guards or fences, which must be replaced after removal.

Work safely at heightsWorking at height is classed as using access equipment. It is the single most frequent cause of accidents, particularly on construction sites. Access equipment includes scaffolds, boom lifts, scissor lifts, ladders and stepladders. Each item has its own inherent hazards, and site safety training should be given before use. They are discussed in more detail later in the chapter.

Know the fire plan for site/buildingAll buildings should have formulated fire plans, which include the provision of fire evacuation routes, assembly points and the location of fire extinguishers. When you arrive at a new place of work familiarise yourself with the plans straightaway.

Know where to get first aidAll places of work should have a first aid plan in place, whether it has a fully equipped medical centre or just a first aid box located somewhere. Make yourself aware of what is available as soon as possible when arriving on site. Remember that even the slightest of cuts and grazes ought to be treated, reported and recorded.

Figure �.0� First aid kit


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Remember

Keep the work area tidy; you will make the job a lot easier to do and help prevent injury

Use good lifting and carrying techniquesMany injuries, which leave the patient unable to carry on working, are caused by incorrect lifting and carrying techniques. It is no longer the done thing to see how much one person can carry against the next. Even in the construction industry manual lifting techniques and devices are available for all heavy load moving. Make sure that you attend courses designed to inform you of these. They are discussed further below.

Building or construction site safetyAll of the above advice and instruction, on working in occupied premises, is applicable to building and construction sites. However, these are a major source of injury and accident and the rules are amended to cover the additional dangers.

The Construction Design and Management (CDM) Regulations have been introduced to reduce the large number of serious accidents and cases of ill health that arise every year as a result of work related to the construction industry. The Regulations apply to all large construction projects that last for more than 30 days and involve more than four people. They do not apply when working for a domestic client, working inside offices and shops when the activities do not interrupt the normal activities of the location, or the maintenance or removal of heating and water systems.

For the MES operative working on any site, the health and safety plan should always be adhered to. The responsibility for the H&S plan belongs to the duty holder, who will have drawn up a site safety plan during the initial planning stages of the contract. The key H&S factors for the MES operative on construction sites are as follows:

Cooperate with the site induction procedures by signing on and off site at the site office.

Wear high visibility clothing at all times, if required to do so.

Obtain, maintain and wear the correct personal protective equipment (PPE), where required to do so.

Use on-site washing facilities before meals.

Keep eating areas clean and tidy.

Cooperate with any special requests in the use of PPE or work methods.

Ensure that access equipment is suitable for the job being done and is certified safe.

Cooperate with access and egress routes. Do not take short cuts across the site.

Identify firefighting requirements, escape routes and assembly points.

Identify the location of first aid facilities.

Observe all safety signs.

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Figure �.0� Safety signs

Prohibition signs

Shape: Circular

Colour: Red borders and

cross bar. Black

symbols on white

background

Meaning:

Shows what must

NOT be done

Example:

No smoking

Mandatory signs

Circular

White symbol on

blue background

Shows what mustbe done

Wear eye protection

Warning signs

Triangular

Yellow background with

black border and

symbol

Warns of hazard ordanger

Danger electric shock risk

Information orsafe condition signs

Square or rectangular

White symbols

on green background

Indicates or gives

information on safety

provision

First aid available

Figure �.0� Checklist for safety helmets


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Remember

On construction sites it normal practice only to allow access when wearing correct PPE (high visibility jacket, safety shoes and hard hat and, in some places, gloves and safety spectacles); if you do not comply you will be sent home

Figure �.0� Safety goggles and glasses


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Figure �.0� Safety boots, helmet, and gloves for general work

On the Job: Safety gearFazal is a first-year apprentice who is starting his first day on a construction site. The H & V fitter in charge gives Fazal a hard hat to wear. Fazal notices that the hat has a crack down one side and reports this to his supervisor. The supervisor tells Fazal that he must wear this hat because there are no more in the store and he needs to get to work.

�. What should Fazal do in this situation?

�. If an object hit Fazal on the head and he was injured because of the crack in the hat, who would be at fault for the injury?

Fire safetyFire is caused by a chemical process called oxidation. Oxidation occurs when oxygen and some other substance meet in the right conditions. The resulting reaction can be slow, as in the oxidation of steel (i.e. rusting), or fast, as in the process of combustion. Fire results when a combustible substance combines with oxygen at a very high rate. Energy is given off from the process in the form of heat and light, which we can see and feel.


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The fire triangleThree things are needed for combustion to occur:

fuel (to vaporise and burn)

oxygen (to combine with the fuel vapour)

heat (to raise the temperature of the fuel vapour to its ignition point).

Figure �.�0 The fire triangle

The fire triangle shows that fire cannot exist without all three elements being present. Therefore, if any one side of the triangle is missing, combustion cannot occur or, if any one side of the triangle is removed, combustion will cease. Firefighting is the act of removing one or more elements of the triangle.

Classes of fire are defined in Table 1.06

Class Materials involved

A Organic solids such as wood or paper

B Flammable liquids

C Gases

D Metals

Table �.0� Fire classification

Fire preventionFires can spread rapidly. Once established, even a small fire can generate sufficient heat energy to spread and accelerate the fire to surrounding combustible materials. Fire prevention is a matter of common sense and good working practices.

Heating equipment is in common use for the joining of pipework and will be the subject of a ‘hot work permit’ in most situations. When heat is to be used the surrounding area should be checked for combustible materials. If present

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Did you know?

Any material will burn, if raised to a sufficiently high temperature in the presence of oxygen

FUEL

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ENHEA

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they should be removed or covered. During and after the time heat is being used a constant watch over the area should be in place. A fire extinguisher should always be at hand during heating operations.

FirefightingIt is dangerous to fight a fire, and the use of fire extinguishers should only be considered as a first response measure, e.g. where the fire is very small or where the fire is blocking your exit route. Firefighting is the job of the professional emergency services.

Fire extinguishersIn the past, the whole of an extinguisher was coloured according to its use but this has been changed and the colour coding is now in accordance with European Standards. These require all fire extinguishers to be red with a coloured label indicating the intended use. Table 1.07 illustrates the most common types. The following points should be remembered when using a fire extinguisher:

Never use a fire extinguisher unless you have been trained to do so.

Read the operating instructions before using a fire extinguisher.

Do not use water or foam extinguishers on electrical fires.

Do not use water extinguishers on oil or fats.

Do not touch the horn of a CO2 extinguisher; it can cause frost burns.

Do not use a CO2 extinguisher in a confined area; it can cause suffocation.

General fire safetyRegular fire drills should be part of the building fire policy, and everyone should cooperate. Fire escape routes and assembly points should be clearly marked at all places of work, even on building sites. If room fire sensors need to be deactivated to enable hot work to be undertaken, it is essential to follow the security procedures for the building. Usually this means informing the building security staff before work starts.

If you discover a fire:

Raise the alarm immediately.

Leave by the nearest exit.

Close all doors as you leave.

Assemble at the designated assembly point.

Ensure that everyone in your team is accounted for.

Stay out of the building until it is safe to return.

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Remember

Personal safety must always come before your efforts to contain a fire. Delay and you will have difficulty in finding your way though the smoke – and the fumes may choke you


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Fire extinguisher types

Standard/multi-purpose dry powder

Colour Blue

Application The powder ‘knocks down’ the flames. Safe to use on most kinds of fire. Multi-purpose powders are more effective, especially on burning solids; standard powders work well only on burning liquids.

Dangers The powder does not cool the fire well. Fires that seem to be out can re-ignite. Doesn’t penetrate small spaces, like those inside burning equipment. The jet could spread burning fat or oil around.

How to use Aim the jet at the base of the flames and briskly sweep it from side to side.

Water

Colour Red

Application The water cools the burning material. You can only use water on solids, like wood or paper. Never use water on electrical fires or burning fat or oil.

Dangers The water can conduct electricity back to you. Water actually makes fat or oil fires worse – they can explode as the water hits them.

How to use Aim the jet at the base of the flames and move it over the area of the fire.

CO2

Colour Black

Application Displace oxygen with CO� (a non-flammable gas). Good for electrical fires as they don’t

leave a residue.

Dangers Pressurised CO� is extremely cold. DO NOT TOUCH. Do not use in confined spaces.

How to use Aim the jet at the base of the flames and sweep it from side to side.

Foam/AFFF (Aqueous Film Forming Foam)

Colour White or cream

Application The foam forms a blanket or film on the surface of a burning liquid. Conventional foam works well only on some liquids, so it’s not good for use at home, but AFFF is very effective on most fires except electrical and chip-pan fires.

Dangers ‘Jet’ foam can conduct electricity back to you, though ‘spray’ foam is much less likely to do so. The foam could spread burning fat or oil around.

How to use For solids, aim the jet at the base of the flames and move it over the area of the fire. For liquids, don’t aim the foam straight at the fire – aim it at a vertical surface or, if the fire is in a container, at the inside edge of the container.

Table �.0� Some fire extinguisher types


Access equipment safety

LaddersLadders are a means of access to and from high level platforms or work surfaces; they are not intended to be used to work from. Stepladders can be used as a working platform, as long the work is of a light nature and short duration, such as adjusting an air conditioning outlet grill.

A visual check should be made for defects each time the item is used. Things to look out for include:

cracks to rungs and stiles

missing or broken rungs

rungs reliant on repairs, or nails or spikes for support

mud, grease or oil on the rungs or stiles

obvious bending of the rungs or stiles

missing or loose screws or rivets

cracked or damaged welds on metal ladders or stepladders

rot, woodworm or tie rods that are missing or damaged

mud, swarf, grease, dirt or stones stuck to the bottom of footwear.

Good ladder practice involves the following:

erected on firm, solid ground

not blocked up with timber or bricks

set at an angle of about 75° (i.e. one out and four up)

project a minimum of 1 metre above working platforms (five rungs)

secured at the top and bottom

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cracks on stiles

splits on rungs

dirt on rungs

temporary repairs

wood rot

damaged tie rods

warping

Figure �.� Ladder with defects

Figure �.�� Fibreglass stepladder

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when climbing, use both hands for grip

maintain three points of contact at all times.

Most of the rules for ladders also apply to stepladders. In addition:

All four legs of the stepladder must rest firmly and squarely on the ground.

Ensure that the legs are fully open.

Check that the hinge is in good condition.

Check that ropes, or other stays limiting opening, are in good condition and the same length.

Do not work from the top step unless it is designed for that purpose.

If not, do not work any higher than with your knees level with the top step.

Mobile scaffold towersTower scaffolds are widely used for access as a working platform but, sadly, they are involved in numerous accidents each year. These usually happen because the tower has not been erected or used properly. Aluminium towers are light and can easily overturn, or can collapse if parts are left out. All tower scaffolds should be erected and inspected by a competent person. It is common practice to indicate safe scaffold towers by a tagging system (scaftags), whereby a status tag is clipped to the scaffold somewhere visible. Any indication of a defective scaffold means that it should not be used.

Good practice when using mobile scaffold towers includes the following:

Make sure that the scaffold is on firm, level ground.

The height of the tower should not be more than three times the minimum base dimension.

Always use the tower with the wheel brakes on.

Access should only be from the outside if it has been designed for access that way, otherwise it should be from the inside of the tower.

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HeinemannNVQ2 Carpentry9pt Zurich BTfig0182Figure �.�� Mobile tower scaffold

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Towers above 2 m in height should have suitable edge protection: 150 mm high toe boards and a hand rail at 910 mm from the working level.

When moving a tower around a site, it is important to look out for overhead power lines that might become a hazard.

Push or pull the scaffold from the base only.

Never move the scaffold with people or materials on the working level.

Scissor and boom liftsScissor and boom lifts are commonly referred to as mobile elevated work platforms (MEWPs) and are becoming popular for their versatility. Use of this equipment is recommended only after training by the supplier.

Figure �.�� Boom and scissor lifts

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Working in excavationsEvery year people are killed or seriously injured when working in excavations. The work has to be planned, managed, supervised and carried out, to prevent accidents. The type of work that could be carried out is the installation of a cold water supply from a boundary connection to a building.

Working precautions for the MES engineer during excavation work include:

Wear a hard hat when working in the trench.

Make sure that the sides are supported or battened to prevent collapse.

Never go into an unsupported trench.

Make sure that materials are not stored too close to the side of the trench.

Make sure that nothing can fall into the trench.

If the excavation is deep, then handrails and toe boards are required around the top.

Ensure that vehicles are kept well away from the excavation.

Be aware of the possible build-up of fumes or gases from vehicles, or working processes such as the use of LPG heating equipment.

Do not work alone in an excavation.

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NVQ PL3. AW_0319. By Stephen Hibberd

Close boardingto trench sides

Horizontalsupports

Adjustablesupport

Drainage pipeSub-soft

Figure �.�� Close boarding of trenches

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Manual handlingThe Manual Handling Operations Regulations 1992, as amended in 2002, apply to a wide range of manual handling operations, including lifting, lowering, pushing, pulling or carrying. The load may be inanimate, such as a box or trolley, or animate, such as a person. Within the MES sector, manual handling can involve items such as scaffolding, tools, pipes, valves, compressors, gas or oxyacetylene cylinders, radiators and boilers.

The duties of employers are listed in Table 1.08.

Employer requirements Employee requirements

Reduce the needs for hazardous manual handling, so far as is reasonably practicable

Follow appropriate systems of work laid down for employee safety

Assess the risk of injury from any hazardous manual handling that cannot be avoided

Make proper use of equipment provided for employee safety

Reduce the risk of injury from hazardous manual handling, so far as is reasonably practicable

Co-operate with the employer on health and safety matters

Inform the employer if you identify hazardous handling activities

Ensure that your activities do not put others at risk

Table �.0� Employer duties in relation to manual handling

Where possible avoid manual handling. Check whether you need to move the item at all or whether it can be broken down into smaller pieces. Can it be moved better using a handling aid, such as a trolley, crane, hoist or fork lift truck?

The movement of loads requires careful planning to identify potential hazards before they cause injury. This involves carrying out a risk assessment of the task, which looks at a number of things, some of which are listed in Table 1.09.


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Unit �0� .� The MES Sector organisation, basic safety and communications

The task Does the task involve:holding loads away from the body?twisting, stooping or reaching downwards?large vertical movements?long carrying distances?strenuous pushing and pulling?repetitive rest or recovery time?insufficient rest or recovery time?a work rate imposed by a process?

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The load Is the load:heavy?bulky, unstable or difficult to grasp?unstable or are the contents likely to shift?sharp, hot or otherwise potentially damaging?

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The working environment

Does the working environment have:space constraints?floors that are slippery or unstable?poor lighting?hot, cold or humid conditions?

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Individual capacity Does the individual:have a reach problem that restricts their physical capacity?have a knowledge of, and training in, manual handling?

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Handling aids and equipment

Is the device the correct type for the job?is it well maintained?are the wheels on the device suited to the floor surface?do the wheels run freely?is the handle height between the waist and the shoulders?are the handle grips in good order and comfortable?are there any brakes and do they work?

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Table �.0� Employer duties in relation to manual handling

There is no such thing as a completely safe manual handling operation but working within guidelines, as shown in Figures 1.20 and 1.21, will reduce the risk. The lifting chart provides a quick assessment.


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Figure �.�� Lifting chart for manual handling

In the diagram, each box contains a guide weight for lifting and lowering in that zone. Observe the activity and compare it with the diagrams. First decide which boxes the operators’ hands pass through. The maximum load that can be moved is the lowest value in any box that the load is to pass through. The guide assumes that the load is readily grasped with two hands and that the operation takes place in reasonable working conditions, with the lifter in a stable bodily position and of average build and strength.

Electrical safetyElectricity can kill. Even non-fatal shocks can cause severe and permanent injury. Shocks from faulty equipment may lead to falls from ladders, scaffolds or other work platforms. Most of these accidents can be avoided with careful planning and straightforward precautions.

The main hazards are:

contact with live parts, causing shock and burns

electrical faults that could cause fires

fire and explosion caused by electrical ignition in an explosive atmosphere.

In harsh conditions, like a building site, the risks are higher. There is greater risk of electrical equipment, extension leads or sockets becoming damaged, and the possibility of water being present which increases the risk of shock. Cramped spaces, especially where there is a lot of metalwork like in a tank or vessel, presents its own problems of electrical safety.

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Shoulder height

Elbow height

Knuckle height

Mid lower leg height

Shoulder height

Elbow height

Knuckle height

Mid lower leg height

3kg 7kg

3kg 7kg

7kg 13kg

10kg 16kg

7kg 13kg

10kg 5kg

20kg 10kg

25kg 15kg

20kg 10kg

10kg 5kg

Did you know?

Each year around �,000 accidents at work involving electric shock or burns are reported to the Health and Safety Executive (HSE). On average �0 of these are fatal. Most of these fatal accidents occur after contact with overhead or underground power lines


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Selecting safe and suitable equipmentChoose equipment that is suitable for the working environment.

The electrical equipment chosen must be within the competence of anyone who is to use it.

Electrical risks can be eliminated by using air, hand or battery-powered tools.

Ensure that equipment supplied is safe and maintained in a safe condition.

In potentially explosive atmospheres use specialist electrical equipment designed for the task.

Use reduced voltage supplies. To reduce the risk of electrical shock in harsh conditions it is better to reduce the voltage by using a step down transformer designed for the purpose. Normal supplies to building and construction sites are 110 volts, denoted by the use of yellow cables and specialist plugs and sockets. When working on steel structures, like boilers, then even lower voltage is recommended, or the use of battery powered tools.

Built into most temporary electrical installations is a protective shut-off switch known as a residual current device (RCD). If an RCD on a transformer trips it is sign that there is a problem somewhere in the system and it should be investigated before being reused.

Good electrical working practicesAnyone working on electrical equipment should be competent to do so.

Regularly inspect and test portable equipment.

Provide an accessible and clearly identified switch near each fixed machine, to act as a power cut-off in an emergency.

For portable equipment, use socket outlets that are close by, so that equipment can be disconnected in an emergency.

The ends of flexible cables should have the outer sheath of the cable firmly clamped to stop the wires from pulling out of their terminals.

Replace damaged sections of cables completely.

Use proper connectors and cable couplers to join lengths of cable.

Protect lamps and other equipment from damage in use.

Any suspect electrical equipment should be taken out of service and labelled ’Do not use’.

Switch off the supply before connecting plugs.

Take extreme care when fault finding on live equipment, especially when others are in the vicinity.

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Remember

Electricity is dangerous, so always take precautions


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First aid for electric shockElectric shock occurs when a person becomes part of the electrical circuit. The severity of the shock will depend upon the level of current and the length of time it is in contact with the body. The lethal level is approximately 50 mA, above which muscles contract, the heart fibrillates (twitches) and breathing stops. A shock current above 50 mA could be fatal unless the person is quickly separated from the supply. Below 50 mA only an unpleasant tingling sensation is felt. However, this may cause you to fall from a work platform, which could in itself lead to serious injury.

Figure �.�� In the event of an electric shock


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Communication and presentationYour appearance and how you communicate is very important. Most of the people you work with outside your own company are non-technical and they will, to a certain extent, judge your work by your appearance and what and how you communicate.

There are several small things that make all the difference to what you portray about yourself and your company.

Personal presentationClean and tidy work wear is an important factor when meeting with a customer or reporting for work on a new site for the first time.

Overalls or other working clothes that have been washed and repaired, and display the company logo, are a good advertisement.

Clean safety shoes, which are suitable for the place you are working in, are a must.

High visibility jackets should be replaced when they become dirty or damaged.

Ensure that security identification badges are clearly visible.

A clean and tidy work area says that you are organised and can work with little disruption to others.

Plan your work so you minimise trips to the store or van, thus saving on time.

Take care of your tools; a clean set of tools gives the impression of being competent at what you do.

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Figure �.�� Some well known tools and equipment


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Communication face-to-faceDuring your working life you will have to talk to all sorts of people about topics such as access to the building, obtaining materials, requesting instructions or negotiating work plans. Some of the people will include:

your client or their representative, for example, an architect or clerk of works

the client’s customers, like the general public in a store

co-workers and management within your own company

other trades like electricians or duct workers.

Communication in the work place will normally take the form of verbal information or requests. Some good rules to follow are:

Know to whom you are talking.

Explain who you are.

Do not get into arguments.

Do not express personal opinions, if this is not appropriate.

Do not make promises you or your company cannot carry out (this is not an effective way of avoiding problems – they always return!).

Be patient and calm when dealing with aggression or complaints. Explain what you are doing, e.g. ‘I am trying to rectify the fault as quickly as possible’.

Keep the customer informed as the job develops.

Communicating by phoneUsing a phone is an effective and quick way to communicate. You will often receive work instructions by phone, report back to your company or order parts. It is important to speak clearly, as the person you are talking to cannot see you.

Good things to remember when answering the phone are:

Answer only if the situation is suitable for taking the call (i.e. not in the middle of a site meeting).

State your name clearly and what company you work for.

Make sure you get (and remember) all the information you need, including the caller’s name and company, and information such as fault and equipment details.

When you are making a call:

Plan in your mind what you are going to say before you start.

State your name and company.

Ensure you are talking to the correct person and remember to take their name. If necessary write it down immediately.

Speak clearly, in a neutral accent if possible.

Be concise if you need to leave a voicemail message.

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Written communicationAlmost certainly you will need to provide information in writing at some point in your working life. It may include service reports, technical reports, letters, memos or time sheets. Aim to keep copies for reference later on. Be clear, accurate and concise and make sure your spelling, punctuation and grammar are correct. If you use a computer then take advantage of the spelling and grammar checking facilities. If you are not too good at spelling, do not be scared of asking for help, or looking up words. Practice makes perfect!

TextingTexting (SMS messaging) is a good way of sending brief information quickly. Ensure that you have stated your name and that the information is accurate. Remember that older people today may not understand some abbreviations in use.

Service and maintenance reports These record your work on site and are part of the system by which your company invoices its customers. It is important that the information recorded is accurate. Different companies have different requirements, but you should make sure you include as a minimum:

your name

the date

description of the work carried out (be concise but include all necessary information and do not use abbreviations, if they are generally not used within your company)

time of arrival and departure

travel time

parts or materials used.

Technical reportsYou might occasionally need to complete a more in-depth report, e.g. following a site visit. Be aware of who will be reading it, so that you can decide how much detail to include and to what technical level. If the reader is technically competent you will be able to use well known terms. If not, stick to general descriptions.

Plan your report before you start, and follow the pattern of an introduction, main body, conclusions, and any recommendations. Present the information logically for the reader, and put detailed information and references into an appendix or appendices. Diagrams and photos help to present information clearly and with minimum text. For example, a plan of a plant room will be clearer and simpler than a description.

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Some golden rules for effective communication are:

be polite, clear, accurate and concise

use technical language only when the receiver can understand it

do not be too technical to non-engineers or technicians

use appropriate language and never swear.

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Remember

It is illegal to use a hand held mobile phone whilst driving. Even if you have a hands free phone, think carefully before using it when driving, as it impairs concentration and you cannot make notes


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Figure �.�� Example service report

Tel: 01567 123456

Fax: 01567 456123

Email: [email protected]

www.getitfixed.com

Get It Fixed Ltd.Arthur Business Park

Anytown

The District

DT12 7XZ

Harcourt Education

High Street

Anytown

The District

DT1 8EW

HARC1High Street

Harcourt Education Ltd

Change nozzle on oil boiler

19/03/2007 David Nicholls 8:00 10:30 Asquoted

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The above work has been carried out to my satisfaction and I agree to pay for all the chargeable work carried out including parts ordered/supplied. I understand that an invoice will

be sent to me for these works and I agree to pay any invoices submitted to me within 14 days of receipt.

(Get It Fixed Ltd. understand and will exercise our statutory right to interest under The Late Payment of Commercial Debts (Interest) Act 1998, if we are not paid according to our

agreed credit terms)

Verbal instructions

Appointment date 19/03/2007 Time 8 am


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Letters and memosA letter is formal and usually addressed to people outside your own company, whereas a memo (short for memorandum) is less formal and usually within the company. Use the same format as a report but with a heading at the start of the letter or memo, stating the subject.

Time sheetsYour time sheets record where you worked, what work you carried out, and the hours worked and travelled. This is the information your company uses to calculate your pay. Make sure you complete them accurately, clearly and on time.

Figure �.�0 Typical time sheet

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Employee’s signature

Supervisor’s signature

Date

Time Sheet Evan Dimmer Electrical contractors

Employee

Date Job No. Start time Finish time Total time Travel time Expenses

Project/site

Mon

Tue

Wed

Thu

Fri

Sat

Sun

Totals


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�. List the main trades within the MES industry.

�. State the employers’ organisation for the MES industry.

�. List two of the government Acts that control health and safety at work.

�. Explain the three factors needed to create combustion.

�. List the procedures to be adopted, if you found a fire where you are working.

�. List the minimum PPE that you require to gain access to a construction site.

�. Why do we need good communication skills?

�. What should be done straightaway, if you find someone receiving an electric shock?

Knowledge check


Heating & Ventilation, Air Conditioning & Refrigeration: Chapter 1

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