Lab Safety Fails That'll Make You Cringe And How To Avoid Them

Question 1 (2 pts) — Identify the missing personal protective equipment (PPE) that your partner should be wearing.

1. Missing PPE list — Your partner needs safety glasses or goggles, a lab coat, and nitrile gloves.

→ Safety glasses/goggles, lab coat, and nitrile gloves

Question 2 (2 pts) — Explain why this specific PPE is essential for handling sodium hydroxide solution.

1. Chemical hazard explanation — Sodium hydroxide is a corrosive base (pH 14) that causes severe eye burns and skin irritation. Safety glasses protect the eyes from splashes; the lab coat protects clothing and skin; gloves prevent skin contact.

→ Safety glasses protect eyes from corrosive splashes; lab coat protects skin and clothing; gloves prevent skin contact with NaOH

Question 1 (2 pts) — What immediate safety action should you take with these unlabeled bottles?

1. Safe handling of unknowns — Stop what you're doing. Do not open or sniff the bottles. Alert the teacher so they can arrange proper identification using the SDS or external testing. Never taste or smell unknown chemicals.

→ Do not open or smell the bottles. Notify the teacher immediately so they can identify the chemicals using the Safety Data Sheet or external testing.

Question 2 (3 pts) — List three pieces of information that must appear on every properly labeled chemical bottle in a New Zealand school lab.

1. Mandatory label components — Every properly labeled chemical bottle must show: 1) Product name and concentration, 2) GHS hazard pictograms, 3) Signal word (Danger or Warning), 4) Hazard statements (e.g., 'Causes severe skin burns'), 5) Precautionary statements (e.g., 'Wear gloves and eye protection'), 6) Supplier name and contact, 7) Date received and expiry date.

→ Product name and concentration, GHS hazard pictograms, signal word, hazard statements, precautionary statements, supplier information, date received and expiry date

Question 1 (2 pts) — Explain why this dilution procedure is dangerous and what could go wrong.

1. Hazard analysis — Concentrated sulfuric acid (18 M) is highly corrosive and exothermic when diluted. Adding water causes rapid heat release, boiling, and violent splashing of hot acid droplets. This can cause severe chemical burns to skin and eyes.

→ Adding water to concentrated sulfuric acid causes violent boiling and splashing of hot acid, risking severe chemical burns and fires.

Question 2 (2 pts) — Calculate the final temperature of the mixture if the reaction releases 15 000 J of heat. Use c = 4.18 J/g·°C for water and assume the density of the final solution is 1 g/mL.

1. Temperature calculation — Rearrange Q = mcΔT to find ΔT = Q/(mc). Plug in Q = 15 000 J, m = 150 g, c = 4.18 J/g·°C. Calculate ΔT then add to initial temperature.
   $$\mathrm{\Delta }T=\frac{Q}{m\cdot c}=\frac{15000}{150\times 4.18}=23.92\text{°C}$$
2. Final temperature — Add ΔT to initial temperature: 20°C + 24°C = 44°C.
   $$T_{final}=20\text{°C}+24\text{°C}=44\text{°C}$$

$$44\text{°C}$$

→ The final temperature is approximately 44°C

Question 3 (2 pts) — Describe the correct procedure for diluting concentrated sulfuric acid.

1. Safe dilution steps — Add the acid slowly to the water in small portions while stirring constantly. Use a magnetic stirrer or glass rod. Place the beaker in an ice bath to absorb excess heat. Wear full PPE including face shield.

→ Add acid to water slowly in small portions while stirring constantly, using an ice bath to absorb heat. Always wear full PPE including face shield.

Question 1 (1 pts) — What gas is released from ammonia solution that makes the fume hood necessary?

1. Gas identification — Ammonia solution decomposes to release ammonia gas (NH₃), especially when heated or agitated.

$${\text{NH}}_3$$

→ Ammonia gas (NH₃)

Question 2 (2 pts) — Why is the fume hood essential for this experiment despite the smell?

1. Health hazard explanation — NH₃ vapours irritate eyes, nose, and lungs. At concentrations above 25 ppm, they cause coughing and breathing difficulties. The fume hood maintains vapour concentration below harmful levels.

→ Ammonia gas irritates respiratory system and eyes; fume hood removes vapours from breathing zone to prevent irritation and toxicity

Question 3 (1 pts) — List two other chemicals commonly used in school labs that require fume hood use.

1. Common fume hood chemicals — Concentrated hydrochloric acid (releases HCl gas), ethanol and other organic solvents, concentrated nitric acid (releases NO₂ gas), and bromine vapour.

→ Concentrated hydrochloric acid, ethanol or other organic solvents

Question 1 (2 pts) — What is the correct disposal method for copper sulfate solution in a New Zealand school lab?

1. Proper collection — Set up a labeled 'Heavy Metal Waste' container in the prep room. After the prac, pour all leftover copper sulfate solution into this container. Do not mix with other waste streams.

→ Collect in a labeled 'Heavy Metal Waste' container and dispose through the school’s chemical waste contractor

Question 2 (2 pts) — Explain why pouring copper sulfate solution down the sink is harmful to the environment and potentially illegal.

1. Environmental harm — Copper sulfate is toxic to aquatic organisms. Even diluted, it bioaccumulates and harms ecosystems. In NZ, discharging heavy metals to stormwater or sewer without consent is illegal under the Resource Management Act.

→ Copper sulfate is toxic to fish and invertebrates and illegal to discharge to waterways under New Zealand environmental law

Question 3 (1 pts) — Where should heavy metal wastes like copper sulfate be stored until proper disposal?

1. Storage requirements — Heavy metal wastes must be stored in a dedicated heavy metal waste container in the chemical store. The container must be labeled with contents, concentration, date, and hazard symbols.

→ In a labeled heavy metal waste container in the chemical store

Question 1 (3 pts) — List the immediate steps you should take in order.

1. Step-by-step response — 1. Alert others to stay clear. 2. Put on safety glasses and gloves from the spill kit. 3. Use the absorbent pads to contain the spill, working from the outside in. 4. Sprinkle sodium bicarbonate (baking soda) to neutralize the acid. 5. Ventilate the area by opening windows or turning on the fume hood. 6. Use paper towels to wipe up neutralized spill.

→ Alert others, don PPE, contain spill with absorbent pads, neutralize with sodium bicarbonate, ventilate area, clean up with paper towels

Question 2 (2 pts) — What should you do after cleaning up the spill?

1. After cleanup protocol — Wash hands with soap and water for at least 20 seconds. Check clothing and skin for any acid contact. Report any exposure or injuries to the teacher immediately.

→ Wash hands thoroughly, check for injuries or chemical contact, dispose of contaminated materials in hazardous waste

Question 3 (1 pts) — Who should you notify immediately after ensuring your own safety?

1. Who to notify — Notify the supervising teacher immediately so they can assess the situation and ensure the spill kit is restocked. The lab technician should also be informed to document the incident and check spill kit contents.

→ Notify the supervising teacher immediately, then the lab technician

Question 1 (2 pts) — Why is this beaker unsafe to use for heating or stirring?

1. Failure modes — The crack creates a stress concentration point. When heated, different parts of the beaker expand at different rates, causing the crack to spread rapidly. Hot liquid can also seep into the crack and cause further weakening.

→ The crack creates a stress point that can cause sudden breakage during heating or stirring, risking hot liquid spills and glass shards

Question 2 (1 pts) — What should you do with cracked glassware immediately?

1. Broken glass protocol — Place the beaker gently into the 'Broken Glass' container lined with puncture-resistant material. Do not wrap it in paper—this can hide sharp edges. Label the container clearly.

→ Place in the designated broken glass container immediately and notify the teacher

Question 3 (1 pts) — Describe the proper way to carry glassware in a lab.

1. Carrying technique — Support the base with one hand and the side with the other. Keep the beaker vertical and close to your torso. Move slowly and watch your path to avoid bumping into others or equipment.

→ Use both hands to support base and side, carry vertically close to body, move slowly

Question 1 (3 pts) — List three possible outcomes of this behaviour.

1. Consequence analysis — Possible outcomes include: 1) A student gets hit in the eye with filter paper, causing a corneal abrasion. 2) A Bunsen burner is knocked over, starting a fire on the bench. 3) Hot equipment or chemicals spill, causing burns. 4) The teacher catches the class and cancels the prac, costing NCEA credits.

→ Eye injury from filter paper, fire from knocked-over Bunsen burner, chemical burns from spills, loss of NCEA practical endorsement for the class

Question 2 (2 pts) — Which safety rules does this behaviour violate? Name at least two.

1. Safety rule violations — This behaviour violates the school’s lab safety code: no horseplay, maintain focus on experiments, never distract others, and always follow teacher instructions.

→ Violates 'no horseplay in lab' and 'maintain focus on experiments' and 'never distract others during practical work'

Question 3 (1 pts) — How should you respond if you see this happening?

1. Student response — You should calmly but firmly tell them to stop. If they ignore you, immediately get the teacher—do not wait for them to 'finish'. Document the incident in the lab log if required.

→ Tell them to stop immediately. If they continue, alert the teacher right away