this will equip you with best knowledge on handling of hazardous chemical

1. By
ESHILOKUN, ADEOLU. O (PhD)

2. OVERVIEW
 INTRODUCTION
 SAFETY LABELS
 LABORATORY CHEMICALS
 LABORATORY SAFETY
 FUNDAMENTAL SAFETY RULES
 SAFE STORAGE
 SAFE WASTE DISPOSAL
 LABORATORY GASES
 ACCIDENT PREVENTION
 RECOMMENDATIONS

3. INTRODUCTION
Good laboratory practices start with you as a
scientist intending to go into the laboratory for
research or teaching.
From the moment you enter the laboratory with
your lab coat and all other necessary gadgets or
apparel as may be relevant to your work or field of
study.

4. SAFETY LABELS
Chemicals and reagents should bear appropriate labels
indicating:
• The hazard symbols and hazard designations
• The risk phrases (R-phrases)
• The safety recommendations (S-phrases)

5. LABELS AND HAZARD SYMBOLS

6. OXIDISING

7. LABORATORY CHEMICALS
Chemicals are exclusively for use in
the laboratory. It is therefore
assumed that the persons using
them know from their professional
training and experience the
precautions necessary in handling
chemicals and materials.

8. Bottle of Ammonia

9. LABORATORY CHEMICALS CONTD.
 On no account are chemicals and reagents permitted
to be used in man. Only small quantities are used in
performing experiments so that dangers to health can
to a greater extent be eliminated.
 For substances for which there are no toxicological
data and which cannot be unequivocally described as
harmless it means hazardous properties cannot be
excluded, so, there will be information such as “Toxic
chemicals, handle with care.”

10. LABORATORY SAFETY
The best safety measure in handling hazardous
materials is through knowledge of the properties of
substances. If the hazard symbols, the risk phrases and
safety recommendations on the labels are heeded, basic
measures to prevent damage to health can be taken.
As a general rule, reagents without a hazard warning
should be handled with the same caution as hazardous
or toxic substances.

11. FUNDAMENTAL SAFETY RULES
The safe handling of laboratory chemicals requires adherence
to some basic rules which are not limited to but include:
• The handling of dangerous substances must be reserved for
qualified personnel.
• When working, always wear protective glasses and if
necessary suitable protective gloves.
• All work should as far as possible be carried out in an
efficient fume cupboard or at least in a well ventilated
rooms.
• Avoid contact with skin, eyes and mucous tissue at all costs

12. FUNDAMENTAL SAFETY RULES CONTD.
 Wipe off splashes on the skin first with a dry cloth,
then immediately with plenty of cold water followed
by washing with hot water and soap. Never use organic
solvents because of the risk of absorption.

13.  Thoroughly rinse eye affected by chemicals with a
special eye shower protecting the uninjured eye. Hold
the eyelids wide open and have the affected person
move the eyes in all directions. Subsequently,
immediately bring the patient to an ophthalmologist
and state the chemical involved.
 Immediately remove any item of clothing soaked with
corrosive substances.

14. Safe Storage
With few exceptions, reagents are
stable chemical substances so that a
manufacturing or expiry date of the
type usually given for pharmaceutical
products is unnecessary.
However, this does not mean that certain
special items do not have optimal
storage temperatures which
significantly contribute towards
quality assurance.

15. It is no coincidence that some reagents are filled into glasses
and others into plastic bottles or ampoules.
Some group of reagents requires special measures to preserve
their quality. Care should be taken in storing chemicals
that sensitive oxidation or reduction e.g. Fe2+ or Fe3+,
substances in these classes of compounds can turn dark
with repeated opening of the storage container and contact
with atmospheric oxygen. Ditto for chemicals that are
sensitive to moisture.
Heat sensitive preparations: certain biological preparations
must be stored in a refrigerator to preserve their properties.
This particularly applies to some enzymes and coenzymes
which because of their thermal instability would suffer a
reduction in activity.

16. Fuming Chemicals
Chemicals which give off corrosive
vapours, e.g . bromine, hydrofluoric
acid, oleum, nitric acid, hydrochloric
acid must be stored in places with
adequate ventilation. Special cabinets
connected to a ventilation system and
fitted with corrosion proof trays can
also be provided.

17. Fuming Hydrochloric Acid

18. Incompatible Chemicals
Part of good laboratory practices is to
know how to manage incompatible
chemicals, i. e chemicals which
because of their properties can react
violently with one another. Therefore
they should be stored separately and
must on no account be allowed to
come in contact with each other.

19. Incompatible Chemicals

20. The purpose of this is for accident prevention both in
the laboratory and in storage.
Examples:
Substance Incompatible With
Acetic acid
Acetylene
Active charcoal
Alkali metals
Nitric acid, alcohols, peroxides,
permanganates, ethylene glycol
Bromine, chlorine, fluorine, copper,
silver, mercury
Calcium hypochlorite, oxidizing
agents
Water, carbon tetrachloride, and
other halogenated alkanes, carbon
dioxide, halogens

21. Aluminium akyls
Ammonia, laboratory gas
Bromine
Chlorine
Chlorates
Copper
Water
Mercury (e. g. in manometers),
chlorine, calcium hypochlorite,
iodine, bromine, hydrogen fluoride
Acetylene, ammonia, butadiene,
methane, butane, propane,
hydrogen, petroleum ether,
benzene, metal powders
As above
Ammonium salts, acids, metal
powders, sulphur, finely-divided
organic substances or other
flammable substances
Acetylene, hydrogen peroxide

22. Flammable liquids
Hydrocarbons (butane, propane,
benzene etc.)
Hydrogen peroxide
Iodine
Mercury
Ammonium nitrate, chromium (VI)
oxide, hydrogen, nitric acid, sodium
peroxide, halogens
Fluorine, chlorine, bromine,
chromium (VI) oxide, sodium
peroxide
Copper, chromium, iron, metals and
metal salts, alcohols, acetone,
organic substances, aniline, nitro
methane, flammable substances
(liquid or solid)
Acetylene, ammonia (laboratory gas
or solution)
Acetylene, ammonia

23. Nitric acid conc.
Oxalic acid
Perchloric acid
Potassium permanganate
Silver
Sodium peroxide
Acetic acid. Aniline, hydrogen cyanide,
hydrogen sulphide, chromium (VI) oxide,
flammable liquids and gases
Silver, mercury
Acetic anhydride, bismuth and its alloys,
alcohols, wood
Glycerol, ethylene glycol, benzaldehyde,
sulphuric acid
Acetylene, oxalic acid, tartaric acid,
ammonium compounds
Methanol, ethanol, glacial acetic acid, acetic
anhydride, benzaldehyde, carbon
disulphide, glycerol, ethylene glycol, ethyl
acetate, methyl acetate, furfurol

24. Safe Waste Disposal
Hazardous wastes must be so collected and transported in
such a way that laboratory users and disposal personnel are
not exposed to risk.
• Waste, which tends to self-ignite, e.g. filters with oxidizing
substances, pyrophoric catalyst residues, incompletely
reacted polymerization residues, must be collected in
containers with a lid consisting of non-flammable material
and the container must be clearly marked and emptied at
the end of each working day by trained personnel.
• Waste which develops toxic and flammable gases and
vapours or which can react with water, for example alkali
metals, metal hydrides and alkyls, carbides and phosphides
must be collected in dry containers and clearly marked so.

25. • Highly-flammable chemicals and flammable
liquids and substances which develop flammable or
toxic gases or vapours with water, acids or alkalis must
not be poured down the drain (for e.g. sodium
sulphide, alkali cyanides), and care must be taken that
no dangerous reactions start during collection for
disposal.
• The disposal of hazardous wastes must be carried
out at a time when the storage, transport and
destruction of the substances does not lead to any
hazards. The disposal and destruction of such
substances must only be carried out by trained and
experienced personnel or specialist waste disposal
companies.

26. LABORATORY GASES
Gases like hydrogen, helium, nitrogen, argon are usually
supplied in pressurized cylinders. Handling pressurized
gases requires thorough knowledge of the risks and
dangers, fire and explosion hazards, toxicity,
uncontrolled escape via incorrect or defective controls.
Pressurized gases should only be handled by trained
personnel, work must only be commenced after careful
study of the properties of the substance and the sources
of hazard.
Of particular importance is the various colours for
different cylinders of gases to avoid the mistake of gas
switching.

27. Handling Pressurized Gas Cylinders
 For storage, choose only well–ventilated dry and fire-
resistant places.
 Protect from exposure to heat and direct sunlight.
 Do not fall pressurized gas containers, even when they
are empty, and secure with chains to prevent accidents.
 Empty gas containers should be clearly marked and
stored separately from full containers.
 Only gases immediately required should be kept in the
laboratory.
 Always close the cylinder valve after use, so that the
withdrawal control do not remain under pressure.

28. Handling Hazardous Gases
Prior to using pressurized gases, note the risk phrases
and safety recommendations according to the
manufacturer guidelines.
When introducing gases into liquids, means must be
incorporated to prevent the liquid from travelling
backwards up the tube or into the withdrawal vessel in
the event of a loss of pressure.
Work with toxic gases should fundamentally only be
carried out in an efficient fume cupboard. Gases which
are hazardous to health should be clearly marked so
with the maximum concentration (in ml/m3 or mg/m3)
of a gas that could be tolerated.

29. Gas Intoxication
Gas intoxication can be caused for example by carbon
monoxide, chlorine, bromine vapours and nitrogenous
gases. When this occurs, open doors and windows
immediatelt to let in fresh air. Do not use open lights
with flammable gases, also do not switch on an electric
light or operate a bell because of danger of explosion
through sparking.
If respiration has ceased, revive by artificial respiration.
Never give an accident victim liquids to drink if
unconscious, rather remove all clothing and wrap victim
in blankets. Immediately transport victim of gas
poisoning to the nearest hospital.

30. Fire Fighting
Fires involving liquefied and compressed gases escaping
from pressurized gas cylinders whose valves can no
longer be closed are extinguished with a powder
extinguisher. For extinguishing fires at the valve, asbestos
hoods connected to a bottle of carbon dioxide via a tube,
which are lowered over the head of the bottle in the event
of fire, thus suffocating the flame have proved highly
effective.
In the case of hot acetylene cylinders, cool with water from
a protected position. If the cylinder is so hot (recognized
by the water boiling), evacuate the area because of the
danger of explosion.

31. Fire Extinguisher

32. RECOMMENDATIONS
 Adherence to all laboratory rules without exception.
 Avoid the use of mobile phones while working in the
laboratory, it may cause distractions.
 For teachers alike, do as you say with or without your
students.
 Avoid receiving or attending to friends/visitors while
working in the laboratory.
 Know the reasons why you are in the laboratory and
follow your schemes and don’t toy with any equipment
you knew little or nothing about.

33. THANK YOU FOR
LISTENING