Hazards and protective measures

Hazards you may encounter

• Mechanical: sharp edges, moving parts, falling objects, slips and trips.
• Physical: noise, high or low temperatures, electricity and radiation.
• Chemical: contact with a harmful substance, inhalation of its vapours, a spill or a dangerous reaction.
• Biological: contact with microorganisms or biological material during certain classes.
• Ergonomic: prolonged awkward posture, repetitive movements and a poorly organised workstation.

Read the label before use

Check the substance name, pictograms, hazard statements and precautionary statements. Do not use an unlabelled container. Do not identify substances by tasting or directly smelling them. When working with chemicals, follow the exercise instructions and the safety data sheet information discussed by the instructor.

What the pictograms mean

• A flame warns of hazards including flammability, while a flame over a circle warns of oxidising properties.
• An exploding bomb indicates an explosion hazard; a gas cylinder indicates gas under pressure.
• The symbol showing liquid dripping onto a hand and metal indicates corrosive effects, while a skull and crossbones warns of acute toxicity.
• An exclamation mark may indicate effects including irritation or harm. A silhouette with a mark on the chest indicates serious health hazards.
• A dead tree and fish indicate a hazard to the aquatic environment. Read the label for the exact type of hazard.

Safeguards first, then protective equipment

Do not remove guards, block switches or bypass safeguards. Use the ventilation and equipment specified for the exercise. Safety glasses, gloves and lab coats are selected for the particular hazard; not every glove protects against every substance. Report and replace damaged protective equipment before starting work.

A spill or leak

Stop the activity, move away from the hazard and notify the instructor. Warn others. Do not touch an unknown substance, mix it with others or try to neutralise it yourself. Cleaning up must follow the procedure appropriate to the substance and the laboratory.

Scenario: an unlabelled container

There is a clear liquid on the table with no description. Do not assume it is water. Leave the container alone and report the missing label to the instructor. A liquid's appearance does not allow its composition to be determined safely.

Risk assessment: from hazard to safeguard

• Describe the task, equipment, substances and people exposed, including bystanders. Include unusual activities: cleaning, malfunctions and transport.
• Identify possible injuries or illnesses, the likelihood of an event and the duration of exposure. Check whether safeguards actually work.
• First remove the hazard or replace the process with a safer one. Then use guards, ventilation and work organisation; personal protective equipment supplements these measures.
• Record the findings: hazards, people exposed, risk level, preventive measures, deadline and the person responsible for improvement. Reassess conditions after an equipment change or an incident.
• Example: liquid spilled in a corridor. A possible consequence is a fall. Restrict access, arrange safe removal of the spill and eliminate the source of the leak. A warning sign alone does not remove the cause.

Chemicals: hazard class and safety data sheet

A class describes the type of hazard, while a category describes its degree within that class. Do not compare categories from different classes as though they formed a single scale. The label combines a pictogram, a signal word and H and P statements. In the safety data sheet, find the hazards, first aid, fire and release response measures, storage and exposure controls. Check compatibility before mixing substances; do not transfer them into beverage containers. Store substances in suitable labelled containers, and hazardous substances and mixtures in designated locked rooms. Do not move them to another storage location without authorisation. Before chemicals are used, the instructor should explain the safety data sheets, hazards and precautions to participants. Ask for this information before starting if it has not been provided.

Carcinogenic, mutagenic and reprotoxic agents

A carcinogenic agent can cause cancer, a mutagenic agent can damage genetic material, and a reprotoxic agent can affect fertility or the development of offspring. The effect may become apparent only after a long time. The absence of pain or smell does not confirm safety. Use a closed process, extraction and the measures specified in the risk assessment. The organiser determines the obligations concerning measurements, exposure records and prevention; students report every unintended exposure.

Biological agents — laboratories and medical classes

Microorganisms can enter the body through damaged skin, mucous membranes, the respiratory tract or the digestive tract. Treat blood and biological material as potentially infectious in accordance with the procedure. Do not eat, drink or store food at the workstation. Use the barriers and protection specified for the activity, minimise aerosol formation, disinfect surfaces and follow the vaccination and preventive measures established for placements. Gloves do not replace hand hygiene.

Hand hygiene: when and how

• When caring for a patient, perform hand hygiene before touching the patient, before an aseptic procedure, after a risk of contact with bodily fluids, and after contact with the patient and their surroundings. Also perform it after removing gloves.
• Remove jewellery that prevents thorough cleaning. Wash visibly dirty hands with soap and water; rubbing in a hand hygiene product alone does not remove dirt.
• Wet your hands, apply soap and rub, in turn, the palms, backs of the hands, spaces between the fingers, backs of bent fingers, thumbs, fingertips and areas around the nails.
• Rinse and dry with a disposable towel. Use the towel to turn off a manually operated tap. The whole washing procedure usually takes 40–60 seconds.
• Apply an alcohol-based product to dry hands in an amount sufficient to cover all surfaces. Rub the same areas until dry, usually for 20–30 seconds; follow the product instructions. Do not immediately wipe it off with a towel.

Sharps: prevent needlestick injuries

Before the activity, prepare a sharps container within reach. Do not leave a used needle loose, bend it or recap it. Use the instrument's intended safety features. Place sharps immediately in a puncture-resistant container; do not push down the contents or reach inside. Pass instruments in the agreed way, avoiding movements made without looking.

After a needlestick injury or contact with biological material

Stop the activity and make the situation safe. Do not squeeze or suck the wound; wash the skin with soap and water. Flush mucous membranes or eyes with water or saline. Immediately report the exposure to the instructor and obtain an urgent medical assessment in accordance with the facility's procedure — do not wait until the end of the class. Record the time, type of instrument and material, and circumstances. A doctor decides whether tests and post-exposure prophylaxis are needed.

Cytostatic drugs — information for medical programmes

Cytostatic drugs inhibit cell division and are used, among other things, to treat cancer. Occupational exposure can occur through the skin, mucous membranes, inhalation of aerosols or a needlestick injury. The risk concerns preparing and administering drugs, disconnecting administration sets, cleaning spills and contact with contaminated waste and excreta. Some drugs are carcinogenic, mutagenic or reprotoxic. Do not perform these activities without training, authorisation and supervision.

Cytostatic drugs: work organisation and emergencies

Use the designated workstation, a closed preparation procedure and protection selected for the drug: an ordinary glove does not guarantee resistance to permeation. Do not eat or drink in the work area. Place contaminated materials in the correct containers. If a spill occurs, isolate the area, warn others and call trained personnel with a spill kit. Do not collect the drug with bare hands or an arbitrary cleaning product. Skin or eye exposure requires immediate action in accordance with the drug instructions and medical assessment. Discuss pregnancy, breastfeeding or other limitations confidentially before tasks are assigned. Pregnant and breastfeeding women must not be employed in work with cytostatic drugs. Agree on a safe scope of placement activities before exposure, rather than after starting the activity.

Electromagnetic fields: recognise the zones

• This applies, among other things, to certain medical and industrial devices. A field can affect the body, interfere with implants and attract ferromagnetic objects.
• The safe zone is outside the protective zones. Access conditions and protective measures based on the exposure assessment apply in the intermediate zone and the hazard zone.
• Being in the dangerous zone is prohibited during everyday practice. Do not treat signs as suggestions or cross the boundary without authorisation.
• Before entering, tell the appropriate person about any implant or medical device. In an MRI facility, follow access and object screening procedures; a phone, keys or a cylinder can pose a hazard. Do not enter to retrieve a dropped object without staff permission.

Ionising and laser radiation

Ionising radiation can damage cells. Limit exposure time, maintain the designated distance and use appropriate shielding; wear a dosimeter if required. Do not activate a source without authorisation or bypass interlocks. A laser can damage eyes and skin, including through a reflected beam. Do not look into the beam or towards it through optical instruments. Shields, eyewear selected for the wavelength and equipment class, and measures to limit reflections must follow the laboratory instructions; ordinary sunglasses are no substitute.

Particularly hazardous work and safety support

Some work requires direct supervision, designated personnel, securing the area and safety support. Working in pairs is not a universal permit to enter an enclosed tank, a radiation zone or work at height. Before work begins, the instructor specifies the allocation of tasks, communication and a rescue plan. Do not attempt an improvised rescue in an unknown atmosphere — call the emergency services and remain outside the danger area.

Check your knowledge

Work through these short scenarios. Check each answer separately.