Health and safety equipment in the lab Flashcards
Give some examples of legislation that governs health and safety in the lab
- COSHH (2002) - covers diseases, especially zoonotic ones, stains and other chemicals used for analysis (eg formalin)
- Health and Safety at Work Act (1974)
- Hazardous Waste Regulations (2005)
- Environment Protection Act (1990)
What are some common hazards in the lab?
Spillages, sharps (needles/blades/glass), flammable substances
What can chemicals be labelled as?
- explosive
- flammable
- gases under pressure
- oxidising
- corrosive
- harmful/irritant
- toxic
- serious health hazard
- harmful to the environment
What are some examples of zoonotic diseases?
- salmonella (from faeces)
- rabies (from affected fluid)
- tetanus
- ringworm (very infectious)
- giardia (caused by parasite-protozoa)
- leptospirosis (from affected urine)
- e-coli (bacteria based)
- campylobacter (caused by a parasite)
- brucellosis (bacteria based - from affected urine, discharge and bodily fluids)
- MRSA (superbug, very resistant to antibiotics, nosocromial)
Define NOSOCROMIAL INFECTIONS
Health care associated or hospital acquired infections
What are some standard rules that should be followed in the lab?
- hair must be tied back
- a lab coat or apron must be worn
- appropriate PEE (gloves/mask/apron) must be worn, do not contaminate pens
- remove jewellery
- wash hands after every exam
What may be included in a lab SOP?
- entry restricted to authorised personnel only
- jewellery must be removed and long hair tied back
- no smoking, drinking or eating in the lab
- the lab must be kept organised and tidy
- cupboards should not be above eye level
- all staff should be aware of potential zoonotic risks
What are the key parts of the microscope?
The eyepiece, the body, the limb/arm, the mechanical stage, the coarse and fine focus knobs, the foot/base, the rheostat, the bulb, the substage condenser, the iris diaphragm, the Vernier scale, the objective lenses, the nosepiece.
Describe the microscope eyepiece
The part of the microscope that the operator uses to view the sample. Contains two lenses, the ocular (closest to the eye) and the field (closest to the scope).
Generally x 10 magnification
Describe the body of the microscope
The main part of the scope; sits beneath the eyepieces
Describe the limb/arm of the microscope
The part of the microscope that should be used to transport it - the scope should be picked up and put down when moving it, never dragged or pulled across a surface
What are the three different types of microscope head?
Monocular, binocular, trinocular
Describe the coarse and fine focus of the microscope
Coarse focus is larger one, fine focus is the smaller one. Both combined raise/lower the mechanical stage to allow the image to be focused
Describe the foot/base of the microscope
Should be supported when transported
Describe the rheostat of a microscope
Alters the level of light intensity produced by the light source
Describe the light source/bulb of the microscope
Has an illuminator condenser lens. Helps to control the light
Describe the substage condenser of a microscope
Sits underneath the stage and moves up and down, condenses light and makes the image sharper and brighter. The iris diaphragm sits on top of the substage condenser, and should be right under the sample
Describe the iris diaphragm on a microscope
Sits on top of the substage condenser. Adjusting this increases or decreases the amount of light passing through the condenser. Helps to ensure a clear sample.
Describe the objective lenses of a microscope
Normally 4 of them. Each of them have a specific purpose
x4 scanning lens
x10 low power lens
x40 high power lens
x100 oil immersion lens
What is the Vernier scale?
Horizontal and vertical vernier scales allows specific placement of specimens to be recorded and relocated
Describe the mechanical stage of a microscope
The flat platform where the slide sits. Has a hole in the middle to allow light to pass through and illuminate the specimen. The stage can be moved up and down with the focus control knobs, as well as horizontally and vertically.
Describe the nosepiece of the microscope
Rotates, and houses the objective lenses
How should microscopes be stored when not in use?
They should be switched off after use, kept in a dust proof box or covered with a plastic sheet. It should be stored away from moisture, heat, and water. It should be cleaned immediately after use and lenses cleaned correctly.
How would you work out the total magnification of a microscope?
It is a combination of the power of the eye piece and the objective lens e.g. if the eye piece is x10 and the objective lens chosen is x40, the total is x400 mag (10x40)
What is the purpose of the scanning lens?
Used to scan for areas of interest on the slide
What is the purpose of the low power lens?
Often used for urine samples and looking for crystals, for faecal egg counts, and for hair and skin samples
What is the purpose of the high power lens?
Used for RBC counts and WBC counts
What is the purpose of the oil immersion lens?
Must be focused on a specific site - the lens cannot move around and must stay in contact with the specimen/oil. Used for looking at FNA samples, differential WBC counts