What are four major physical hazards associated with compressed gas cylinders?
They can explode if heated or damaged.
A ruptured cylinder or broken valve can turn the cylinder into a rocket or fragmentation bomb.
Sudden release of high-pressure gas can puncture the skin and cause a fatal embolism.
Rapid release can displace air, creating an oxygen-deficient atmosphere.
How should gas cylinders be secured during storage, handling, and transport?
They must be firmly secured in an upright position using suitable racks, chains, or stands. They should be secured to an architectural support, not to a table or mobile equipment.
What is the proper way to transport a gas cylinder?
Use a four-wheeled hand truck or dolly. Do not roll or drag the cylinder.
What must be done with the valve safety cap on a gas cylinder, and when?
Leave the valve safety cap on until the regulator is attached. Replace the cap for storage or transport.
Where should gas cylinders be stored in relation to the main laboratory?
Gas cylinders should be stored in an area separate from the laboratory. Only cylinders that are connected to apparatus should be present in the lab.
What is the correct way to check a gas cylinder system for leaks?
Apply a soap solution to all connectors. Bubbles will indicate a leak.
What steps should be taken when a gas cylinder is not in use?
Close the main cylinder valve and bleed the residual pressure from the gas delivery system.
How should empty gas cylinders be prepared and handled?
Mark or tag them as “empty,” replace the valve safety cap, store them secured in an upright position, and return them to the supplier promptly.
What is a cryogenic fluid, and what is a common example used in clinical labs?
Cryogenic fluids are liquefied gases at very low temperatures (usually below -73.3 °C). A common example is liquid nitrogen, used for freezing and storing biological materials.
What are the main physical hazards of cryogenic materials?
High pressure buildup in the container.
Embrittlement of materials (making them brittle and prone to shattering).
Severe burns and tissue damage (especially to eyes).
Fire hazards due to the potential to condense oxygen from the air, creating oxygen-rich environments.
What personal protective equipment (PPE) should be worn when handling cryogenic material?
Impervious clothing, full face protection, and insulated gloves.
Why is there a risk of explosion or pressure buildup when removing specimen containers from cryogenic storage?
As the container warms up, the internal pressure increases significantly. Eye protection should be worn until this pressure is released.
List four ways electricity can cause harm.
It is a potential ignition source for fires.
It can burn human tissue along the current’s pathway.
It can cause muscle contraction and ventricular fibrillation by affecting the nervous system.
It can be fatal, even at low voltage and current (e.g., 25 mA from a 100V source).
What factors determine the risk and severity of electric shock to a person?
Duration of contact
Voltage
Current
Pathway of current through the body (through the heart is most dangerous)
Moisture content of the skin (dry skin offers more resistance)
Susceptibility of the individual (e.g., people with cardiac problems)
Why should extension cords and multiple adaptors be avoided in a laboratory?
The lab should have enough permanent outlets to avoid their use. Extension cords and adaptors can be tripping hazards and are not a substitute for proper wiring.
What should you do if electrical equipment becomes wet?
Shut off the power at the circuit breaker or fuse box before attempting to clean up.
What type of fire extinguisher should be used on an electrical fire?
Only Class C extinguishers should be used on electrical fires.
What is ionizing radiation?
Radiation that has enough energy to displace an electron from an atom or molecule, thereby producing ions.
Name four sources of ionizing radiation.
X-rays, gamma rays, alpha particles, and beta particles. (Neutrons are also a source).
What is the difference between an external exposure and an internal exposure?
External exposure is from radiation sources outside the body that can penetrate deeply (like x-rays and gamma rays).
Internal exposure occurs when a nuclear substance is inhaled, ingested, or absorbed through the skin or eyes.
What are some late (chronic) effects of radiation exposure that can appear years later?
Leukemia and other malignancies (cancers).
Which organs are at the greatest risk from radiation exposure?
Blood-forming cells (bone marrow), breasts, thyroid, lungs, digestive system, and a fetus.
Why is it important to choose the correct shielding material for a radioactive source?
Choosing the wrong shielding can lead to harmful secondary radiation emission. For example, lead should not be used to shield P-32; Plexiglas should be used instead.
What is the first step to take for both a minor and a major radioactive spill?
Notify all persons in the immediate area that a spill has occurred.
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Introduction25
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Introduction Quiz10
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Legislation20
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Legislation Quiz9
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Occupational Health and Safety Management Systems24
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Occupational Health and Safety Management Systems Quiz10
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Good Laboratory Safety Practices – The Basics28
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Good Laboratory Safety Practices – The Basics Quiz10
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Hazard Identification and Risk Assessment8
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Hazard Identification and Risk Assessment Quiz10
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Biological Hazards110
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Biological Hazards Quiz11
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Chemical Hazards26
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Chemical Hazards Quiz10
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Physical Hazards34
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Laboratory Ergonomics26
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Psychological Hazards33
