The document discusses safety hazards in clinical hematology laboratories. It identifies biological, chemical, electrical, and fire hazards as the main dangers. For biological hazards, it emphasizes taking proper precautions like training, use of personal protective equipment, and vaccination. Chemical hazards are also reviewed in detail, stressing labeling, storage, and ventilation procedures. Electrical and fire hazards are examined as well, noting the importance of equipment maintenance and infrastructure design. Overall prevention relies on training, proper protocols, hygienic practices, and an emergency management plan.

1. Author: Negash Alamin
Occupation: Clinical labscientist
E-mail: drnegash@gmail.com
Date: 29/12/17

2. Introduction
Safety is an essential part of laboratory practice even preceding the diagnostic procedure. Safety
for the worker, patient, visitors, managers and house keepers in the laboratory comes as a priority
not just in hematology department but in every department of the clinical laboratory. As it is
obvious the laboratory is the infectious area in the hospital it is where samples are drawn and
deposited for analysis. Thus, there is an elevated risk of infection to all that either work in it or
are just visiting every corner and every inch as well as equipment has the potential to transmit
some sort of infectious agent. It will be wise to consider the lab as a ‘pathogen zoo’ so that
effective and essential precautions are taken to minimize the risk of injury.

3. Main article
What are the overall potential dangers in hematology laboratory?
 Biological hazards
 Chemical hazards
 Electrical hazards
 Fire hazards
Biological hazards
It is an occupation hazard that many laboratory workers encounter daily exposure to biological
hazards. These hazards are present in various sources throughout the laboratory such as blood
and body fluids, culture specimens, body tissue and cadavers, and laboratory animals, as well as
other infected workers [1] number refers to reference index.
Figure 1 International symbol for biohazard
In a typical clinical laboratory the worker may only be exposed to geographically prevalent and
common pathogens in the his community; but, in a research hematology laboratory the level of
risks increase exponentially exposing the worker to the most virulent and dangerous pathogens
like:
 HBV
 HCV
 HIV1
 EBOLA
1
HIV is one of the two pathogens with Hepatitis virus strains C, B, etc. that pose a real threat to the workers
because they are problematic to cure; especially HIV viral strains which have no cure or vaccine for now.

4.  Avian flu
 Anthrax
 Fungi
 SARS
The blood is the most important tissue in the body; it is the body’s high way system linking
every organ with one another; thus there is an elevated risk for the accumulation of dangerous
pathogens of every kind inside it. Thus, even though all samples must be considered infectious;
the blood ranks among the most infectious. The best example is HIV which has a higher
concentration of virus in the blood than any other body sample due to the circulating CD4 cells
in the blood which the virus has affinity for. Therefore, blood samples and hematology
department has a high risk of infection to workers and visitors alike.
What should be the prevention method for biological hazards?
 Appropriate training of laboratory personnel in the protocol of Hazard prevention and
available reading materials like safety guidance documents must be available in the a lab
or the library from responsible organization of the country in which the worker practices
in the case of the USA it is OSHA or the CDC.
 Appropriate PPE procedures must be followed by the workers at all times like gloves,
gowns, splash guard helmets (see figure 2) or goggles when opening vials which contain
blood samples.
 There must be a SOP procedure written and placed in the laboratory according to the lab
protocol for the analysis of samples and that must be followed strictly.
 Prophylaxis like HBV and TB vaccines must be provided by the employer to the worker
free of charge which is actually part of the workers right list.
 The laboratory manager bears the responsibility for lab hygiene organization and safety.
Thus, he must overlook safety protocol.
 The practice of procedures appropriate to the workers skill i.e. workers should not
practice or analyze samples beyond their training.
 Physicians must be informed of workers which incurred injury like needle stick injury; so
that workers could get appropriate medical attention and reduce the transmission of
pathogens form worker to worker.
 In the case of advanced research on laboratory animals; specific care and regulation of
research must be followed to prevent infection form the animals of interest.
 Never eat, drink, smoke, handle contact lenses, apply cosmetics, or take or apply
medicine in areas where blood samples are handled.

5.  Keep hands away from your mouth, nose and eyes2
.
 Infectious samples must be labeled ‘infectious’.
 Always be up-to-date with the latest research on safety procedures from the publication
of credible organizations which regulate safety and perform research on infectious
disease.
 Safe decontamination and disposal of biological waste materials.
 There must be appropriate use of safety cabinets in accordance to the risk of the
pathogen.
 Be cautious whenever using sharp objects like needles whenever possible. Never remove,
recap, bend, break, or clip used needles from disposable syringes. Use safety
engineered needles when practical.
 Laboratory cleaning workers other than pathologists need to be informed as well as
trained efficiently on how to clean the benches, microscopes, ESR tubes, slides, and other
laboratory equipment with the appropriate operating manual and chemicals for each
device.
 Furthermore, cleaning staff are the most exposed and at risk for infection than the
workers thus, they need to be trained very well on the pathogenesis of viruses and
bacteria and as said above what type of chemicals they should use for disinfection.
 Wear tear-resistant gloves to prevent exposure. Micro-tears in the gloves may
compromise the protection they offer. Remove gloves and wash hands according to the
standard after handling patient samples.
 Utilize the appropriate method of wearing and removing gloves.3
 Use mechanical pipetting devices (no mouth pipetting!).
 The laboratory must have an emergency management plan4
ready for any potential
accidents with samples.
Chemical hazards
In hematological procedures the chemicals utilized are dangerous and caustic that can cause
burns like HCL which is used in hemocytometry of WBC; chemicals like methanol can cause
blindness by damaging the optic nerve if mistaken for a beverage; it is used as a fixative in
Giemsa staining procedure in parasite diagnosis. Other nocuous chemical that comes to mind are
bleach and formaldehyde which are used for disinfection of the benches with 1:10 dilution in
case of hypochlorite and formaldehyde used as a fumigant agent to sterilize incubators.
2
They are unprotected membranes unlike the exotic integumentary system which has a layer of dead cells as
protection.
3
See the images on page 12 of the Textbook: Hematology: Clinical principles and applications: 2012 Bernadette
Rodak MS,MLS et al
4
A written document

6. The list of harmful chemicals in all of laboratory is voluminous there are carcinogens,
explosives, caustic and irritants based on their nature; but this paper only deals with the ones
utilized in hematology laboratory and I think I have mentioned all of them above.
Figure 2 One of the several safety signs in the lab
But generally the following points below summarize on how to handle chemicals:
 Label all chemical properly; do not use chemical without labels and do not guess.
 The name, concentration the chemical, preparation date, expiration date, name of
preparer and chemical labels such as posioness, corrosive, or flammable in accordance
with the nature of the chemical (see figure 1)
 Follow all instructions concerning handling and storage requirements for the chemical
that probably came with the manufacturer called ‘material safety data sheets’ which can
be stored and read later on to understand the chemical purchased; they contain:
1- The name of the manufacturer.
2- Exposure dangers ex. Carcinogen, irritant, teratogen, mutagen etc.
3- Physical and chemical characteristics of the chemical.
4- The physical hazards it possesses.
5- Reactivity of the chemical.
6- Precautions for safe handling.
 Store flammable chemical like methanol mentioned above in safety cans or storage
cabinets at a distance of 2 meters away from the heat sources like Bunsen burners etc.
 Only store working solution in the working bench for no more than 2 days. [2]
 Do not store chemicals together that could create a reaction. [3]
 Work in a well-ventilated area if you are working with irritant and toxic chemicals.
 Utilize appropriate PPE for that specific chemical you are handling.

7.  Safety showers and eye drainage or washing corners must be built in the laboratory to
address acid and alkaline chemicals spills and the procedures to be performed must
either be posted as a sticker or written as a document.
 Do not carry chemical vials without their appropriate container.
 Do not wear contact lens when dealing with chemicals because if accidents occur it will
be hard to clean the eyes. [4]
Figure 3 A splash guard where blood samples are open behind the glass to prevent spills on the face
Electrical hazards
 Electrical hazards could occur in a laboratory if plug-ins for cables not built properly.
 The socket and cables are faulty without proper plastic cover.
 Handling electrical cables with wet hands.
 Low quality machines which have not passed quality testing.
 Unstable current from utility providers which can damage equipment and may be even
start a fire.
Fire hazards
 Fire could start in a laboratory due chemical and electrical interaction; for example
flammable chemicals should be stored away from direct flame and faulty electrical
machines and wiring.
 Overheating machines could start fire in the lab due to overwhelming workload.
 It important to utilize flames like Bunsen burners in a safe setting.
 The lab must be well ventilated.5
 Do not smoke in the laboratory!
 Some chemicals are explosive even in vapor state; thus, read carefully the manual that
comes with them and store them appropriately.
5
See Monica Chessbrough’s book part one; chapter 3; page 54 a topic entitled ‘Guidelines for a Code of safe
laboratory Practice’ for a good and terse detail on safe working environment.

8.  The most vital thing of all is that the infrastructure of the lab must be well planned as
well as constructed to avoid fire hazards and must include emergence exists, plans and
procedures if it occurs.
Conclusion
Generally we have mentioned the issues which can occur as a result of several hazards and the
manner how to manage those issues in a lab with the intention that these rules for medium sized
laboratories; but, in case of advanced research labs we can also include radiation hazards which
can emanate from radioactive substances. We have seen what type of issues facilitates the
manifestation of unfortunate hazards and the points that needs to be taken in order to make the
lab safe for workers and patients alike. I hope the above document provides some sort of
essential guidance on how to make safety a daily privilege in the lab.
References
 Hematology: Clinical principles and applications: Bernadette F. Rodak MS, MLS et al
2012 [2], [3].[4]
 Occupational safety and health hazard administration: 2011
www.osha.org [1],
 Medical laboratory technology: Ramnik Sood: 2006