learning outcome lesson objective environmental issues
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Learning Outcome Lesson Objective Environmental Issues
Understand the implications of the issues and constraints on
building construction Lesson Objective To be able to explain the
environmental impact resulting from materials and methods used in
construction Environmental Issues Recap L04: Understand the
implications of the issues and constraints on building
construction
What are the main threats to environmental sustainability? Global
warming a gradual increase in the overall temperature of the
earth's atmosphere generally attributed to the greenhouse effect
caused by increased levels of carbon dioxide, CFCs, and other
pollutants Resource depletion Both renewable and non-renewable
Pollution Air, water, and land Which is the most immediate? Global
warming as resource depletion and pollution contribute to it. L04:
Understand the implications of the issues and constraints on
building construction
What are the three areas that link together to provide sustainable
development? The triple bottom line L04: Understand the
implications of the issues and constraints on building
construction
Construction activities statistics Energy from fossil fuels
consumed in the construction and operation of buildings accounts
for approximately half of the UKs emissions of carbon dioxide.
Construction and Sustainable Development Plain English,
Constructing Excellence, Section 2, Page 5, 01/01/08 More than 400
million tonnes of materials get delivered to site each year. Of
these 60 million tonnes go straight to tip due to over ordering,
damage resulting for poor storage or because of inappropriate
ordering. Time to bin industrys lavish habits by Mike Baker,
Thursday 20th March Construction News, Issue 7060 Over 90% of
non-energy minerals extracted in the UK are used to supply the
construction industry with materials. Construction and Sustainable
Development, Plain English, Constructing Excellence, Section 2,
page 4, 01/01/08 L04: Understand the implications of the issues and
constraints on building construction
What can we do? Designers? Contractors? Building users? L04:
Understand the implications of the issues and constraints on
building construction
Raising the standards. The code for sustainable homes is the
national standard for the sustainable design and construction of
new homes. It aims to reduce carbon emissions and promote higher
standards of sustainable design above the current minimum standards
set out by thebuilding regulations. L04: Understand the
implications of the issues and constraints on building
construction
The code for sustainable homes The code provides 9 measures of
sustainable design: energy/CO2 water materials surface water runoff
(flooding and flood prevention) waste pollution health and
well-being management ecology In groups of 2/3 discuss what could
be incorporated under each heading. L04: Understand the
implications of the issues and constraints on building
construction
The code for sustainable homes It uses a 1 to 6 star system to rate
the overall sustainability performance of a new home against these
9 categories. The code is voluntary. The only circumstances where
the code can be enforced are where: local councils require
developers to comply with the code by including a requirement in
their planning policy affordable housing is funded by the Homes and
Community Agency that requires homes to be built to code level 3
the level 3 energy standard is now incorporated in the building
regulations L04: Understand the implications of the issues and
constraints on building construction
The code for sustainable homes How would living in a Code 6 home
benefit the homeowner? Lower energy consumption Greater water
efficiency Better air quality Environmental kudos L04: Understand
the implications of the issues and constraints on building
construction
Extraction and manufacture What are fossil fuels? Fossil energy
sources, are non-renewable resources that formed when prehistoric
plants and animals died and were gradually buried by layers of
rock. Over millions of years, different types of fossil fuels were
formeddepending on what combination of organic matter was present,
how long it was buried and what temperature and pressure conditions
existed as time passed. Fossil fuels are:- Oil Gas Coal L04:
Understand the implications of the issues and constraints on
building construction
What are the disadvantages of using fossil fuels? Fossil fuels are
non-renewable energy resources. Their supply is limited and they
will eventually run out. Fossil fuels release carbon dioxide when
they burn, which adds to the greenhouse effect and increases global
warming. Of the three fossil fuels, for a given amount of energy
released, coal produces the most carbon dioxide and natural gas
produces the least. Coal and oil release sulfur dioxide gas when
they burn, which causes breathing problems for living creatures and
contributes to acid rain. L04: Understand the implications of the
issues and constraints on building construction
Our economy is largely dependent on fossil fuels. Reducing CO2
emissions is the most significant issue when constructing
buildings. Designers and contractors have a duty to produce homes,
and buildings that are energy efficient, reduce heat loss and have
energy efficient appliance. In groups discuss how a home could be
made more energy efficient. L04: Understand the implications of the
issues and constraints on building construction
Consider how different construction methods affect the environment.
Prefabrication Sourcing locally Waste segregation Discuss and list
the advantages associated with each. L04: Understand the
implications of the issues and constraints on building
construction
Complete waste worksheet L04: Understand the implications of the
issues and constraints on building construction
Material Choice What is embodied energy? The embodied energy
(carbon) of a building material can be taken as the total primary
energy consumed (carbon released over its life cycle). This would
normally include (at least) extraction, manufacturing and
transportation. L04: Understand the implications of the issues and
constraints on building construction
How can energy used to manufacture and deliver materials be
reduced? Try to reuse materials and topsoil already on site, and
give preference to low energy materials. Source materials locally,
reducing delivery journeys and supporting the local economy. Ensure
that contractors do likewise by examining their supply chain Use
reclaimed materials (e.g. second-hand timber) and recycled
materials (such as glass / concrete or brick rubble for aggregates)
for construction. L04: Understand the implications of the issues
and constraints on building construction
What are the advantages of using local materials? Contributes to
lowering carbon emission levels and saving resources by reducing
carbon miles in transporting goods. Could save on packaging and
transport costs. Strengths local economy by keeping money in the
area which could help to create new jobs within the local
community. Buying from a local independent business can benefit
from local knowledge and expertise and often, the price difference
is minimal due to transport savings. Cost savings from 'bargain'
online suppliers could be lost if a long-distance delivery doesnt
turn up on time, arrives damaged or incomplete. This could cause
major delays for a project and with contractors hanging around
waiting for a delayed delivery, this will add to the budget.
Learning Outcome Lesson Objective Environmental Issues
Understand the implications of the issues and constraints on
building construction Lesson Objective To be able to explain the
environmental impact resulting from materials and methods used in
construction Environmental Issues Noise Pollution L04: Understand
the implications of the issues and constraints on building
construction
Noise What is noise? Definition-unwanted sound by the listener
Sound a wave motion carried by the air Units the decibel (dB),
using a logarithmic scale, which means that an increase of 10 dB
equates to a doubling in loudness L04: Understand the implications
of the issues and constraints on building construction
Noise propagation Noise will generally radiate in all directions,
it will bend around and over walls and buildings It will reflect
back off solid surfacescertain operations will generate more noise
in one direction than another so careful orientation can have
benefits Screening between source and receiver is effective if it
obscures the direct line of site between the two L04: Understand
the implications of the issues and constraints on building
construction
Why is noise important? Excessive noise on site can represent a
major hazard to site workers andannoy neighbours Noise is the
source of the majority of off-site complaints Noise can disturb
wildlife and natural heritage L04: Understand the implications of
the issues and constraints on building construction L04: Understand
the implications of the issues and constraints on building
construction
Controls Limiting the time for noisy activities Introduce screening
between source and receiver Controls at source Working noise level
dB (A) Average noise allowed
L04: Understand the implications of the issues and constraints on
building construction Working noise level dB (A) Average noise
allowed Actualworking time allowed 75 60 minutes 78 30 minutes 81
15 minutes 85 6 minutes L04: Understand the implications of the
issues and constraints on building construction
Managing noise on site Threefactors which influence noise levels at
a given point: Site management and construction method Plant
Screening L04: Understand the implications of the issues and
constraints on building construction
Checklist duty of care Change working method Reduce noisy assembly
practices (off-site) Isolate noisy plant Adopt working hours to
restrict noisy activities to certain times Arrange delivery times
to suit the area Route construction vehicles to take into account a
reduction in noise and vibration Maintain haul roads Liase with
conservation bodies to minimise noise disturbance (disruption) to
any sensitive wildlife L04: Understand the implications of the
issues and constraints on building construction
BACKGROUND Noise pollution is traditionally not placed among the
top environmental problems facing the society; however, it is one
of the more frequently encountered sources Sources of noise
pollution are extremely diverse and are constantly increasing as
more and more noise-generating products become available to
consumers. An estimated 6% citizens are exposed to noise that poses
a threat to their hearing. In today's mechanized world it is
virtually impossible for an active person to avoid exposure to
potentially harmful sound levels. L04: Understand the implications
of the issues and constraints on building construction
It is often possible to reduce noise radiation from production
equipment, material handling, and work in progress; for example by
damping sound radiating panels, quietening power sources and
transmissions, and reducing noise from compressed air exhausts.
Sometimes machine alterations or enclosures do not give
sufficiently good results, and if it is the work process itself
which causes intense noise it can be difficult to predict the
results of noise control measures. In such cases effort might be
better aimed at changing the working methods and processes
themselves. L04: Understand the implications of the issues and
constraints on building construction
Changing the method of work is the only way to get to grips with
noise generation; it requires that production equipment or part of
it must be replaced and one must be aware of the availability of
less noisy equipment for both production and material handling.
Requires cooperation between the buyer, supplier, designer, and
safety organization. L04: Understand the implications of the issues
and constraints on building construction
Preventing propagation to avoid noise pollution can result
economically more efficient than corrective measures. The noise in
a workshop is often dominated by a relatively small number of
intense noise sources. Try to enclose all noise sources points or
keep them away from workers in the same room. By setting up sound
absorbing ceiling and wall panels, noise levels within the room far
from the noise sources can be reduced. Alteration and replacement
of production equipment may mean that personnel monitoring this
machinery do not need to be in its vicinity if monitoring can be
carried out in a sound insulated control room. Learning Outcome
Lesson Objective Environmental Issues
Understand the implications of the issues and constraints on
building construction Lesson Objective To be able to explain the
environmental impact resulting from materials and methods used in
construction Environmental Issues Dust Pollution L04: Understand
the implications of the issues and constraints on building
construction
Control of Dust L04: Understand the implications of the issues and
constraints on building construction
Nuisance dust activities are a common and well-recognised problem.
Fine particles (less than 10 m in diameter, known as PM10) from
these sources are now recognised as significant causes of
pollution. Why? Owing to their small size, they can be carried from
sites even in light winds and may therefore have an adverse effect
on the local environment and on the health of local residents, as
well as on those working on the site. L04: Understand the
implications of the issues and constraints on building
construction
Under Part IV of the Environment Act, (1995) and the UK Air Quality
Strategy, Local Authorities are required to work towards achieving
national air quality objectives. Construction site operators will
therefore need to demonstrate that both nuisance dust and fine
particle emissions from their sites are adequately controlled and
are within acceptable limits. L04: Understand the implications of
the issues and constraints on building construction
Health effects from particles and fibres from certain materials are
immediate while those from other types of materials may take many
years to develop. It is therefore essential that exposure to all
forms and sizes of particle pollution is kept to a minimum, both
for workers on site and for other people living and working outside
the site boundary. L04: Understand the implications of the issues
and constraints on building construction
In groups of 2/3 discuss and list the benefits of reducing dust
pollution lessening of the impact on local air quality reduction in
the soiling of property, thereby reducing the costs of cleaning
reduction in the level of complaint from local residents reduction
in the number of environmental offences and hence prosecutions by
Local Authorities less time and money wasted in defending
prosecutions and repairing environmental damage reduction in the
site engineers workload by avoiding conflicts potential for
increased future business enjoyment of the benefits of increased
profit. L04: Understand the implications of the issues and
constraints on building construction
How can dust be controlled? Dust and fine particle generation from
construction and demolition activities can be substantially reduced
through carefully selected mitigation techniques and effective
management. Once particles are airborne, it is very difficult to
prevent them from dispersing into the surrounding area. The most
effective technique is to control dust at source and prevent it
from becoming airborne, since suppression is virtually impossible
once it has become airborne. L04: Understand the implications of
the issues and constraints on building construction
Dust control measures commonly used L04: Understand the
implications of the issues and constraints on building
construction
Worksheet task Consider how dust is created by the following
activities, and how they can be mitigated. Roads, surfaces and
public highways Static and mobile combustion plant emissions Site
preparation and restoration after completion Demolition
Construction and fabrication processes Internal and external
finishing and refurbishment L04: Understand the implications of the
issues and constraints on building construction
before after L04: Understand the implications of the issues and
constraints on building construction
The main problems we experience concerning dust L04: Understand the
implications of the issues and constraints on building
construction
What is Silica? Silica is one of the most abundant minerals on
earth and found naturally in masonry, stone, sand and aggregates.
Its also used in the manufacturing of a huge range of building
materials including bricks, blocks, mortar, roof tiles and concrete
products. Materials containing silica are perfectly safe, but when
the materials containing silica are subjected to everyday site
activities such as cutting, drilling, grinding and sanding, very
fine dust particles can be released into the air. L04: Understand
the implications of the issues and constraints on building
construction
SUBSTANCE % SILICA CONTENT Brick Up to 30 Concrete, cement, mortar
25 to 70 Tile 30 to 45 Sandstone, gritstone, quartz More than 70
Granite Sand, gravel, flint Slate Up to 40 L04: Understand the
implications of the issues and constraints on building
construction
Silcosis When you breathe in air containing dust, the hairs and
mucus in your nose and throat trap the large dust particles but the
fine RCS particles are respirable meaning they are carried deep
into the lungs where oxygen is extracted from the air. The RCS
particles are deposited here causing inflammation and scarring
known as silicosis, which makes breathing more difficult and
increases the risk of developing lung infections and lung cancer.
L04: Understand the implications of the issues and constraints on
building construction
Environmental Protection Act (EPA) (1990) The EPA (1990), under
Section 79, states that where a statutory nuisance is shown to
exist, the Local Authority must serve an abatement notice.
Statutory nuisances are defined as: any dust or other effluvia
arising on industrial, trade or business premises and being
prejudicial to health or a nuisance any accumulation or deposit
which is prejudicial to health or a nuisance. Legislation relating
to occupational exposure
L04: Understand the implications of the issues and constraints on
building construction Legislation relating to occupational exposure
Health and Safety at Work Act (1974) This is the principal statute
for reducing health and safety risks and protecting people during
workplace activities. It is a criminal statute and does not give
rise to any civil liability. The Control of Substances Hazardous to
Health (COSHH) Regulations, (1994) Under COSHH Regulation 2, one of
the definitions of substances regarded as hazardous to health
includes: dust of any kind, when present in substantial
concentration in the air. L04: Understand the implications of the
issues and constraints on building construction
Clean Air Act (1993) Under the Clean Air Act (1993), open fires are
not recommended on site since emissions of dark smoke are
prohibited from any industrial or trade premises (e.g. construction
or demolition sites). However, the burning of timber and other
waste resulting from the demolition of a building is exempt from
this. The following conditions, however, are essential for the
exemption to apply. There must be no other reasonably safe and
practicable method of disposal. The emission of dark smoke must be
minimised. The burning must be carried out under direct and
continuous supervision.