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Laboratory
Practice and Professional Skills 1
Professional Development - Study Skills
This
page allows restricted access to self-paced tutorials and guidance
materials for undergraduate students registered in the Department
of Chemical and Forensic Sciences. The tutorials and guidance
notes cover:
Whether
you are working in a chemistry or biomedical sciences or pharmacy
laboratory or anywhere else on university campus, it is essential
that your work is carried out with regard to your own safety and
the safety of others. The notes that follow are intended as a
generic introduction to good health and safety practice in the
laboratories. You will need to consult the handbooks given to you
at the start of each laboratory course for full details.
C&FS
Safety Handbook You will have been given a Safety
Handbook as part of your registration documentation and will need
to have read the two statements of declaration contained in the
Handbook, and signed and returned them to the department before
being allowed to carry out any practical work in the Chemical and
Forensic Sciences laboratories. The C&FS Safety Handbook can
also be accessed HERE
(access restricted to registered students). The Safety Handbook
gives complete details of your obligations to the department and
to your fellow students, and the department's duties to you and it
describes the university's procedures for maintaining a safe
environment for all people working on its premises. The following
important requirements should be carried out at all times.
Clothing
You must wear a laboratory coat and a pair of safety
spectacles (or suitable prescription lenses) at all times whilst
in the laboratories in the department of Chemical and Forensic
Sciences. Your laboratory coat must be fastened. You can expect to
be asked to leave the laboratory if you do not adhere to these
simple requirements. Your footwear should be sufficient to provide
adequate protection against the accidental spillage of chemical
reagents and glassware. Open sandals are not adequate. Your
protective clothing should be stored in the locker provided for
you when you are not carrying out practical laboratory work.
Eating,
Drinking and Smoking Under no circumstances are you
allowed to bring food or drink into, or consume them in, the
department's laboratories. You must not chew gum or smoke
cigarettes in the laboratories. If you are found to do so, you
will be required to leave the laboratory and may not be permitted
to return. There will be periodic opportunities for you to take
refreshment or smoke in designated areas of the campus during
practical laboratory sessions. It is not good practice to wear
laboratory coats in areas where food is dispensed or consumed and
you will in fact be required to remove such clothing before being
allowed into the university cafeterias.
Accidents
in the laboratory Accidents happen all the time, even
to the most conscientious of workers. It is therefore important
that you NEVER work in a laboratory
alone. Always make sure that there is at least one other person
nearby.
If
an accident occurs, you should report the fact immediately, no
matter how trivial it may seem. This includes minor spillage of
reagents and breakage of glassware or instruments as well as
personal injury and when you have been exposed to substances
(e.g., on or through your skin, or eyes, or mouth). Some
substances have debilitating effects long after exposure to them.
Any injury to persons or exposure to hazardous substances has, by
law, to be recorded in the department's injury logbook. The
department will take every reasonable step to remedy an incident,
but if you do not make a report and are later found to suffer
illness as a result of the incident, you will forego the
opportunity to receive any necessary treatment to alleviate
symptoms and could be personally liable for the consequences.
The
Laboratory Record A good experimenter always
records what they did, when they did it, and details about what
they observed or found and they write these things down in a
notebook (the Laboratory Record) at the time they carry out the
experimental work. You should record you work in a notebook for
this purpose. You should NEVER make
notes on loose pieces or sheets of paper. If you are found to do
so, your notes will probably be taken from you and you might then
need to repeat your work to obtain the necessary record of your
results. You should write in ink. If you make a mistake, cross it
out so that the original can still be seen and enter the details
again. Do NOT use any
correction fluid (e.g., Tippex™) to repair or conceal mistakes.
It is important that these records are as comprehensive as
possible because they will be used by you, often days or weeks
after carrying out the experiment, when you write-up a full
Laboratory Report.
The
Laboratory Report The Laboratory Report should be
written in a hard-backed notebook with your name written on the
front cover of the notebook. Each report should be dated and the
Title for the experiment given at the top of the first page for
that report. Each new Laboratory report should be started on a new
page. Each page should have a ruled margin of no less than 2.5cm
(1 inch) down the left side of the page. Generally, a laboratory
report should be divided into five*
parts, with the following headings:
-
Introduction
In this part you should state what the experiment set out to
do
-
Experimental
You should describe here what you did (past tense, not written
in the first person). It should be sufficiently detailed for
another person to follow without reference to any other work.
-
Results
Your observations and results should be presented in a clear
and legible fashion.
Calculations should be presented in full
Tables, Figures and Graphs should be given
Headings
Axes on Graphs should be labeled and given
appropriate scales
-
Discussion
It is in this section where you analyse your findings,
manipulate your data and answer any questions, as required in
the laboratory script.
-
Conclusions
Finally, you should summarizes the outcome of your
experimental work.
*
It is perfectly acceptable to combine
parts 3 and 4 into a section headed Results and Discussion.
You
can, if you wish, word process your Laboratory Report. If you
choose to do so, the report should be double spaced, each page
should be numbered and the pages should be stapled or bound
together with a front sheet containing the Title of the
Experiment, the date on which the experiment was carried out and
your name.
Further
or more specific details will be given to you by the academic
tutor responsible for your laboratory classes.
All
substances supplied to the department and used in its laboratories
have been assessed by the manufacturer and/or supplier to
determine whether the substance is harmful to man, to what extent
it is harmful following exposure to it, the maximum permitted
levels of exposure in law, and how exposure should be controlled
to minimise risk to health. These data and other are collected
together in Material Safety Data Sheets (MSDS). If you are using a
substance and wish to know whether it is hazardous, you should
obtain the MSDS for that substance.
There are many sources of
MSDS, and some of these have been brought together for access, on-line.
You can also obtain safety data and related information from the
university
library and the department's chemicals store.
The legislation
covering MSDS is provided by CHIP, the Chemicals
(Hazard Information and Packaging for Supply) Regulations 2002.
MSDS
contain a good many acronyms and safety-related terminology. The
following tutorial shows you what these terms mean and how to use
MSDS in assessing hazards.
Answers
to the questions in the self-paced tutorial will be provided in
the next class session.
Click
HERE
It
is a legal requirement for all employers and service providers to
put into place processes for the assessment of risks to health
wherever hazardous substances are used. Carrying out a risk
assessment is just one step in a process involving other important
issues, such as controlling exposure to hazardous substances,
monitoring the health of workers, and keeping employees
informed. The whole process, including the assessment of risks to
health, is known as a COSHH (Control of Substances Hazardous to
Health) assessment.
All experiments you will
carry out in the department's laboratories have been
"COSHH assessed" for you. These assessments are kept in
the department for consultation and are reviewed from time to time
to ensure continuing safety and best practice.
If
you are interested, you can read the Control of Substances
Hazardous to Health (COSHH) Regulations 1999 (S.I. 1999 No 437),
and various Approved Codes of Practice (ACoPs). Details about the
requirements of COSHH at
http://www.hse.gov.uk/coshh/index.htm.
The full primary legislation can be viewed on-line at Her
Majesty's Stationary Office: S.I.
1999 No 437.
Whether
or not you read the full legislation, it is important that you
know how an assessment of risks and of potential exposure to
hazardous substances is carried out, and you also need to know how
to present the findings of an assessment in a structured way - by
completing a "COSHH form."
So
what do COSHH forms look like? Well, there is no single answer to
this question. The following list of examples, taken from other
university departments around the UK, show just how diverse COSHH
forms can appear. Take a look at them all.
Now
that you know what a COSHH form can look like, it is time to carry
out an exercise in which you will make an assessment of risks and
complete a COSHH form. The exercise is in two parts. The first
part was considered in an introductory session. The details you
were given are also provided
here.
Details
of how to carry out a risk assessment and of how to complete a
COSHH form can be found at the COSHH
Essentials web site, and indeed in many other places.
To
help you with the exercise, you would do well to work through the
example which has been made available to you here.
You will need to have worked through this material before
proceeding to the second part of the exercise, which
involves completion of the COSHH form.
COSHH
is only one part of a wide range of safety-related information.
Other information about health and safety is available from the
University's Health
and Safety Services web pages.
Further
Legislation is available at:
Statutory Instrument 2000 No. 289
The Dangerous Substances and Preparations (Safety) (Consolidation)
and Chemicals (Hazard Information and Packaging for Supply)
(Amendment) Regulations 2000
Statutory Instrument 2000 No. 2381
The
Chemicals (Hazard Information and Packaging for Supply)
(Amendment) Regulations 2000
Despite
the increasing use of computers in chemistry and the availability
of ever-increasingly sophisticated hand-held calculators, these do
not always give results which are expressed in a realistic way.
For example, the result of a calculation to determine the
concentration of hydrogen ions in solution might produce the
answer, 0.0988036 moles per decimetre cubed. Is it necessary or
realistic to give this answer to this many figures? Do you know
how many figures should be used? Do you know the meaning of the
term "significant figures"? Do you know the difference
between writing out numerical answers to a given number of
significant figures as opposed to decimal places? This tutorial
will guide you through these questions.
Whenever
you carry out an experiment, errors are introduced. Some of these
are avoidable and some are not. Avoidable errors include
incorrectly carrying out instructions and performing practical
experimentation in a sloppy fashion including the poor use of
laboratory equipment. Both are examples of human error and they
occur when people make mistakes. When experiments are carried out
properly, especially experiments requiring measurements, errors
are still introduced. These are called experimental errors, they
occur because there is always some uncertainty in any measurement,
and they are unavoidable. Knowing how to quantify and treat this
type of error is vital in any branch of science involving
measurement.
All
branches of the physical sciences involve numbers and units or
more precisely, physical quantities, the product of a pure number
(e.g., 2) and a physical dimension (e.g., grams). Although
computers and or hand-held calculators are routinely used to carry
out numerical manipulations, they do not (unless programmed to do
so) give the units to the answer. Since the units of a numerical
answer should always be given, knowing about units, how to use and
convert them are important aspects of any calculations you make.
For example, you may weigh out a quantity of a solid reagent on a
digital balance (in grams) and dissolve the solids in a known
volume of water (in ml) but be required to give your answer in
milligrams (mg) per microlitre (ml).
Having arrived at the numerical answer, dimensional analysis will
help you to discover whether the magnitude of the numerical part
of your answer is correct and quantity calculus will help you
derive the correct units for the quantity.
The
UK Government have passed legislation to standardize the use of
units of measurement!! These regulations are known as the The
Units of Measurement Regulations 2001 Statutory Instrument 2001
No. 55. These can be viewed at: http://www.legislation.hmso.gov.uk/si/si2001/20010055.htm.
Access to the coursework
assessment will be made available here on Blackboard in week 8 of
the first semester. Coursework must be handed in to M22
(the C&FS /Pharmacy office) no later than Friday 11th December
2006 (week 11). Please note that failure to comply with
the deadline for submission of work will earn
you zero marks.
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