Chemistry lab safety rules: How to stay safe

If it’s your first time in a chemistry lab, perhaps your mental picture of lab-work involves a ‘mad scientist’ working with dangerous chemicals, setting things on fire, and blowing stuff up.

While this is unlikely to be a realistic image of your first experiment (at least we hope not!), it is true that the lab has the potential to be a dangerous place.

Working in the lab is a bit like driving a car. Driving on the motorway at high speed would be deadly if you ignored the basic rules, for example by driving the wrong way or speeding through red lights. But respecting the simple rules keeps drivers safe. Similarly, there is nothing to fear in the lab as long as the basic safety rules are followed.

Read on for some simple tips on how to minimize the risks before you enter the lab, and how to react if a dangerous situation does break out. Then, test your skills in our Chemistry Safety simulation and experiment with dangerous chemicals without putting yourself in real danger.

Here are the basic chemistry safety rules:

What to wear

• Long hair should always be tied back

• No sandals. Your feet should be covered.

• Wear gloves when appropriate

• Wear safety goggles

• Wear a lab coat. Put your lab coat on before you enter the lab, fully buttoning up, to protect you from nasty chemicals. Remember to take it off when you leave to prevent contamination of other areas.

Know what you’re working with

Check the bottle of any chemicals you work with for a GHS hazard symbol. Hazard symbols are a globally recognized way of classifying and labeling chemicals, with 8 pictograms that enable you to quickly identify any dangerous properties of what you’re working with:

Flammable.

If you see this, you know the chemical ignites easily. You should therefore keep the chemical away from oxidizing substances (see below), flames or sparks.

Oxidizing.

These substances are known to cause oxidation reactions. They should be stored separately to flammable chemicals, because even though they don’t burn themselves, they can speed up the development of a fire and make it more intense.

Corrosive.

These chemicals can wear away materials like skin or clothing, and potentially cause burns. All the more reason to wear a lab coat and eye protection! Be sure to wash these chemicals off your skin instantly if you spill.

Acutely toxic.

If a chemical is toxic, avoid getting it on your skin and handle with care in the fume cupboard (see next section for more information on what the fume cupboard is).

Harmful.

Chemicals with this symbol aren’t necessarily poisonous, but they can still cause harm to your body.

Explosive.

Explosive chemicals have energy stored in them, meaning they could explode if not treated correctly. It is illegal to carry out unauthorized experiments with explosive chemicals.

Compressed gas.

Compressed gases should be handled with caution to prevent them blasting. You should for example not heat them.

Health Hazard.

Exposure to this chemical could damage your health. For example, it might be carcinogenic.

Another system for communicating the hazards of chemicals is the Fire Diamond, which you can read about in our lab safety blog post.

If you want more information about what a chemical might do to the world, what it’s made of, and how to handle it, you can look up its Material Safety Data Sheet. Your lab should have a collection of these, or you can find them on the manufacturers website.      

Learn how to use the fume hood

The fume hood is a contained, ventilated work bench that contains airborne chemicals and removes them through an exhaust fan.

• Make sure it is turned on. This is needed to maintain the air flow that protects you.

• Place your reagents in the back of the bench. If they are too close to the front, it is more likely that harmful vapors will flow out.

• Never put your head inside the fume hood.

• Keep the glass cover down. If might feel unnatural working with a piece of glass right in front of you but it is necessary to maintain the airflow and prevent fumes escaping. The cover can also protect you from potential blasts.

Know how to dispose of your chemicals

Chemicals which are organic (this means they contain carbon) cannot just be flushed down the sink. They need to be collected in separate waste containers and burned.

Where you should dispose of your organic solvents depends on whether or not they are halogenated (contain halogen atoms like bromine, chlorine or iodine):

• Halogenated solvent waste. Halogenated waste needs to undergo expensive treatment which involves burning it at high temperatures to prevent it forming toxic substances.

• Non-halogenated solvent waste. Non-halogenated waste can be burned at lower temperatures and reused, hence it is much cheaper to process it. Pouring even small amounts of the halogenated waste into the non-halogenated waste bin is wasteful as the whole bottle will need to be disposed of as halogenated waste.

Think fast! Learn how to react to dangerous situations

Despite our best efforts to prevent them, accidents happen. All it takes is a momentary lapse of attention. It’s natural to panic, but if you’ve thought through what to do beforehand you have a much better chance of responding well.

Here’s what to do in response to these 4 different types of accident.

1. A minor injury

• The first aid kit is used for minor injuries such as cuts.

2. A small, contained fire

• Attempt to smother it. For example if it’s in a flask, cover it with a lid.

3. An out of control fire

• Only if you are trained should you attempt to use a fire extinguisher to fight the fire. If in doubt, get out.

• Ensure the safety of everyone around.

• Raise the fire alarm

• Press the circuit breaker so that all of the machines in the lab will be turned off.

• Evacuate through the emergency exits. These ensure that nobody can get trapped in case of a fire, and therefore should always be kept clear. Evacuation plans should be placed near the exits.

• Fire blankets can be used to protect yourself.

4. A person catches fire

• Encourage them to stop, drop and roll to extinguish their clothes.

• If there’s a safety shower nearby use that to extinguish the fire.

• Don’t ever wrap a fire blanket around them as this can create a ‘chimney effect’ and burn their face.

Do you know where to locate each of the pieces of safety equipment in bold in your lab?

Practice your good lab safety technique in our Chemistry safety simulation as you help fight climate change by creating sustainable biodiesel from algal oil. By using a virtual lab, you can make mistakes and learn from them before it really counts, allowing you to enter the the lab with confidence!