Write a risk assessment for Part B: Conducting the Practical You will carry out the experiment using the method below: Materials: Water baths (30oC, 40oC, 50oC, 60oC) 200mL Sodium percarbonate solution 4 x Pre-stained cloth swatches 1 x Stirring rods 1 x Timers 4 x Beakers (100mL) 1 x 100mL measuring cylinder Thermometer Method: 1. Label 4 beakers with appropriate temperature (30oC, 40oC, 50oC, 60oC) and your initials. 2. Measure out and add 50mL of sodium percarbonate solution into each beaker. 3. Place beakers in water baths with a thermometer. 4. Label 4 cloth swatches with appropriate temperatures and take a photo with appropriate labels. 5. When beaker has reached desired temperature, place labelled pre stained cloth swatch into beaker and stir. Make sure cloth is completed submerged in the solution. 6. After 20mins, remove beakers from water baths and stir again. 7. Remove cloth swatch from beaker and dry. 8. Once cloth is dry, take a photo with appropriate labels. 9. Import photos and calculate CYMK value from centre of stain from both before and after photos.
Laboratory Risk Assessment and COSHH Safety Guidance for Sodium Percarbonate Cleaning Experiment
Assessment Date: [DATE]
Assessor: [ASSESSOR NAME]
Department/Area: [DEPARTMENT/AREA]
Review Date: [REVIEW DATE]
1. Assessment Scope
This assessment covers the preparation, handling, use, heating, stirring, removal, drying, and disposal of sodium percarbonate solution used with pre-stained cloth swatches in beakers placed in 30°C to 60°C water baths during a school laboratory practical. It includes associated activities such as labeling containers, measuring and transferring solution, using thermometers and stirring rods, handling hot water baths and glassware, responding to spills, and managing waste after the experiment. The assessment applies to students, teachers, technicians, and any supervising staff involved in setting up, conducting, or clearing away the practical. It excludes unrelated laboratory activities, large-scale chemical storage, and any use of equipment or chemicals not specified in the practical unless they are introduced as part of local school procedures.
2. Risk Assessment Methodology
A task-based job hazard analysis was used to identify hazards at each stage of the practical and evaluate the likelihood and severity of harm before and after controls. Controls were selected using the hierarchy of controls, prioritizing elimination, substitution, engineering controls, administrative controls, and PPE. Chemical hazards were considered using COSHH principles, including safe handling, exposure prevention, spill preparedness, and waste control. Risk ratings are expressed using a consistent qualitative scale: likelihood (Rare, Unlikely, Possible, Likely, Almost Certain), severity (Negligible, Minor, Moderate, Major, Catastrophic), and overall risk rating (Low, Medium, High, Extreme).
3. Risk Matrix Reference
The following matrix is used to evaluate risk levels based on likelihood and severity:
| Likelihood | ||||||
|---|---|---|---|---|---|---|
| Rare | Unlikely | Possible | Likely | Almost Certain | ||
| Severity | Catastrophic | Low | Low | Low | Medium | Medium |
| Major | Low | Low | Medium | Medium | High | |
| Moderate | Low | Medium | Medium | High | High | |
| Minor | Medium | Medium | High | High | Extreme | |
| Negligible | Medium | High | High | Extreme | Extreme |
4. Hazard Identification and Risk Evaluation
1. Contact with sodium percarbonate solution, which is an oxidising cleaning chemical, during weighing, mixing, transfer, or use in beakers.
Potential Consequences: The solution may cause eye irritation, skin irritation, or aggravation of existing dermatitis. Splashes may contaminate clothing or surfaces and may damage some materials if not promptly cleaned. Incompatible mixing or poor handling may increase the likelihood of exposure.
Affected Persons: Students, teachers, technicians, and nearby persons in the laboratory.
Initial Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Possible | Moderate | Medium |
Control Measures
- Eliminate unnecessary handling by preparing only the minimum quantity required for the practical.
- Use a clearly labeled, dedicated container and avoid decanting into unmarked vessels.
- Use engineering controls such as stable bench setup and secondary containment trays during transfer.
- Apply administrative controls including teacher demonstration, clear instructions, and supervision during all chemical handling.
- Wear suitable PPE including safety glasses or chemical splash goggles, laboratory coat or apron, and chemical-resistant gloves matched to the task.
Residual Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Unlikely | Minor | Low |
2. Eye exposure from splashes of sodium percarbonate solution or hot liquid during pouring, stirring, or removing swatches from beakers.
Potential Consequences: Eye irritation, pain, temporary vision impairment, or more serious injury if a hot or concentrated splash occurs.
Affected Persons: Students, teachers, technicians, and anyone standing close to the work area.
Initial Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Possible | Major | High |
Control Measures
- Use chemical splash goggles rather than ordinary safety glasses where splash risk exists.
- Keep beakers below eye level and pour slowly to reduce splash generation.
- Use a funnel or pouring aid where appropriate and keep containers stable on the bench.
- Restrict the number of people working at the bench to reduce crowding and accidental contact.
- Provide immediate access to an eyewash station and ensure users know how to activate it.
Residual Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Unlikely | Moderate | Low |
3. Skin contact with pre-stained cloth swatches, contaminated solution, or wet surfaces during handling and drying.
Potential Consequences: Minor skin irritation, staining, contamination of clothing, and transfer of chemical residue to eyes or face through hand contact.
Affected Persons: Students, teachers, technicians, and cleaners handling the materials after use.
Initial Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Likely | Minor | Medium |
Control Measures
- Use tongs, forceps, or stirring rods to handle wet swatches rather than bare hands where practicable.
- Wear gloves suitable for chemical handling and wet materials.
- Keep hands away from the face and enforce handwashing after glove removal.
- Use absorbent pads or trays for drying to prevent spread of contamination.
- Remove contaminated gloves carefully and replace them if damaged or heavily soiled.
Residual Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Unlikely | Negligible | Low |
4. Burns or scalds from 30°C to 60°C water baths, hot beakers, heated solution, and steam during heating and removal.
Potential Consequences: Contact burns to hands and forearms, scalding from spilled hot water, and secondary injury from dropping hot glassware.
Affected Persons: Students, teachers, technicians, and anyone assisting with the water bath.
Initial Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Possible | Major | High |
Control Measures
- Use the lowest temperature that achieves the learning objective and avoid unnecessary heating.
- Use a thermostatically controlled water bath or monitored hot-water container rather than open heating where possible.
- Handle hot beakers with tongs, heat-resistant gloves, or beaker carriers.
- Keep the work area clear and dry to reduce the chance of slipping while carrying hot items.
- Mark hot equipment clearly and instruct students not to touch glassware until it has cooled sufficiently.
Residual Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Unlikely | Moderate | Low |
5. Breakage of glass beakers, thermometers, or stirring rods during setup, stirring, transport, or cleaning.
Potential Consequences: Cuts from broken glass, contamination of the experiment, and possible splashes of chemical or hot liquid if breakage occurs while heated.
Affected Persons: Students, teachers, technicians, and cleaners.
Initial Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Possible | Major | High |
Control Measures
- Inspect glassware before use and remove chipped, cracked, or damaged items from service.
- Use appropriate-sized beakers and avoid overfilling to reduce breakage and spill risk.
- Transport glassware on trays and keep it away from bench edges.
- Use gentle stirring with a glass rod or alternative non-metallic stirrer and avoid forceful contact with the beaker base.
- Provide a brush and dustpan or glass disposal container for safe cleanup of broken glass.
Residual Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Unlikely | Moderate | Low |
6. Spills or splashes of sodium percarbonate solution, hot water, or contaminated rinse water onto benches or floors.
Potential Consequences: Slip hazards, skin or eye exposure, damage to surfaces, and delayed cleanup leading to secondary incidents.
Affected Persons: Students, teachers, technicians, and anyone walking through the laboratory.
Initial Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Likely | Moderate | High |
Control Measures
- Use spill trays or secondary containment under beakers and water baths.
- Keep containers capped or covered when not actively in use.
- Clean spills immediately using the correct local spill procedure and warn others to keep clear.
- Place absorbent materials and waste containers within easy reach before starting the practical.
- Maintain dry walking routes and prohibit running or unnecessary movement in the laboratory.
Residual Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Unlikely | Minor | Low |
7. Incorrect labeling, misidentification, or unsafe storage of sodium percarbonate solution, stained swatches, or waste containers.
Potential Consequences: Accidental misuse, incompatible mixing, exposure to unknown contents, and improper disposal of chemical waste.
Affected Persons: Students, teachers, technicians, cleaners, and waste handlers.
Initial Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Possible | Moderate | Medium |
Control Measures
- Label all prepared solutions and waste containers clearly with contents and hazard information according to local school procedures.
- Keep chemicals in their original containers where possible and do not transfer to unmarked vessels.
- Segregate waste from clean materials and keep stained swatches in designated containers.
- Provide verbal and written instructions on what each container is for and who may handle it.
- Dispose of waste promptly after the practical rather than leaving it on benches or in sinks.
Residual Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Rare | Minor | Low |
8. Poor use of thermometers and stirring rods, including splashing, breakage, or contact with hot liquid while measuring temperature or mixing.
Potential Consequences: Minor burns, eye splashes, broken glass, inaccurate results, and increased likelihood of spills.
Affected Persons: Students and supervising staff.
Initial Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Possible | Minor | Medium |
Control Measures
- Demonstrate correct thermometer insertion depth and safe stirring technique before the practical begins.
- Use a thermometer suitable for the temperature range and ensure it is intact before use.
- Stir slowly and keep the rod below the liquid surface to avoid splashing.
- Do not use excessive force when placing or removing the thermometer or rod from the beaker.
- Supervise closely when students are measuring temperature or transferring equipment.
Residual Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Unlikely | Negligible | Low |
9. Waste handling and disposal of used sodium percarbonate solution, stained cloth swatches, and contaminated consumables after the experiment.
Potential Consequences: Exposure during cleanup, blocked sinks, environmental contamination, and contact with residual chemical on waste materials.
Affected Persons: Students, teachers, technicians, cleaners, and waste contractors.
Initial Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Possible | Moderate | Medium |
Control Measures
- Collect used swatches and contaminated disposables in a designated waste container rather than leaving them on benches.
- Follow local school and COSHH waste procedures for disposal of chemical residues and contaminated materials.
- Do not dispose of waste in a way that creates splashes or aerosolization.
- Rinse equipment only if local procedures permit and ensure rinse water is managed safely.
- Wash hands after cleanup and before leaving the laboratory.
Residual Risk Assessment
| Likelihood | Severity | Risk Rating |
|---|---|---|
| Unlikely | Minor | Low |
5. General Control Measures
- Apply the hierarchy of controls before relying on PPE, using engineering and administrative controls to reduce exposure wherever practicable.
Use stable benches, secondary containment, supervised workstations, and clear task sequencing so that students handle the minimum amount of chemical and hot liquid necessary. [3] [7]
- Complete a hazard assessment before the practical and review it whenever equipment, processes, or chemicals change.
Document the task, hazards, controls, and PPE requirements before the lesson and update the assessment if the water bath temperature range, chemical concentration, or apparatus changes. [4] [10]
- Provide suitable eye, hand, body, and foot protection matched to the hazards present.
At minimum, use eye protection for splash risk, gloves for chemical and wet handling, lab coats or aprons for body protection, and closed-toe footwear with long trousers in the laboratory. [7] [1] [2]
- Maintain good laboratory housekeeping, clear labeling, and controlled access to the work area.
Keep benches dry and uncluttered, label all containers, restrict access to active workstations, and ensure only trained persons handle chemicals and hot equipment. [6] [7]
- Ensure emergency equipment and spill response materials are available and that users know the response procedure before starting.
Provide access to eyewash, first aid, spill kit materials, and a clear route to the sink or emergency wash area. Brief students on what to do if a spill, splash, burn, or breakage occurs. [7] [8]
6. Emergency Preparedness
- Eye splash response: Immediately flush the affected eye(s) at the eyewash station with clean water for the time required by local school procedure, hold eyelids open, and seek medical assessment if irritation persists or if a significant splash occurred.
- Skin contact response: Remove contaminated clothing or gloves, rinse the affected skin with plenty of water, and wash with mild soap if appropriate. Escalate to first aid if redness, pain, or blistering develops.
- Hot liquid or burn response: Cool the burn under cool running water for an appropriate period, do not apply ice or creams unless directed by first aid guidance, and report all significant burns immediately to the supervising teacher or first aider.
- Spill response: Stop work, warn others, isolate the area, and clean the spill using the approved spill kit and local procedure. Prevent spread to floors or drains and dispose of cleanup materials as contaminated waste.
- Glass breakage response: Do not pick up broken glass by hand. Use brush and dustpan or tongs, place fragments in a designated sharps or broken-glass container, and inspect the area for small shards before resuming work.
- Emergency escalation: If there is a serious injury, uncontrolled spill, fire, or suspected chemical exposure beyond first aid, stop the practical, alert the supervisor, and follow the school emergency communication and evacuation procedure.
7. Training Requirements
- Chemical Safety and COSHH Awareness: Students and staff must be trained to understand the hazards of sodium percarbonate solution, safe dilution and transfer methods, exposure routes, and the importance of avoiding skin and eye contact. Training should also cover reading labels and following local COSHH procedures for storage, use, and disposal. [5]
[7]
- Recognize oxidising and irritant properties.
- Follow label instructions and local school rules.
- Report spills, splashes, and damaged containers immediately.
- PPE Selection, Use, and Limitations: Users must be trained to select and wear PPE that matches the hazard, including when to use safety glasses versus chemical splash goggles, how to wear gloves correctly, and how to remove contaminated PPE without self-contamination. Training should also explain that PPE is the last line of defense and does not replace safe work practices. [4]
[7]
- Inspect PPE before use.
- Replace damaged or contaminated PPE.
- Do not wear laboratory PPE outside the laboratory.
- Hot Water Bath and Glassware Handling: Training must cover safe handling of hot water baths, hot beakers, thermometers, stirring rods, and glassware. Users should know how to transport hot items, how to avoid splashing during stirring, and how to check glassware for damage before use. [6]
[9]
- Use tongs or heat-resistant gloves for hot items.
- Keep glassware away from bench edges.
- Allow equipment to cool before drying or packing away.
- Spill, Breakage, and Emergency Response: All participants must be instructed in the local response to chemical spills, hot liquid burns, and broken glass incidents. Training should include when to stop work, how to isolate the area, and how to summon help promptly. [7]
[8]
- Know the location of eyewash and first aid equipment.
- Use the correct cleanup tools for broken glass.
- Report all incidents and near misses.
- Laboratory Housekeeping and Waste Disposal: Training should cover safe drying of samples, segregation of contaminated waste, and disposal routes approved by the school. Users must understand that waste and contaminated materials should not be left on benches or disposed of casually in sinks unless local procedures explicitly allow it. [6]
[4]
- Use designated waste containers.
- Keep benches dry and uncluttered.
- Wash hands after cleanup.
8. Monitoring and Review
Review Frequency: Annually and after any incident, near miss, change in chemicals, equipment, or procedure
| Monitoring Type | Frequency | Responsible Party | Description |
|---|---|---|---|
| Pre-use inspection | Before each practical session | Teacher or laboratory technician | Check beakers, thermometers, stirring rods, water bath setup, labels, spill kit availability, and PPE condition before students begin work. Remove damaged glassware or unsuitable PPE from service immediately. |
| Supervisory observation | During each practical session | Teacher | Observe student handling of chemicals, hot water baths, and glassware to confirm that safe stirring, transfer, and removal methods are being followed and that crowding around the bench is controlled. |
| Housekeeping and spill check | During work and at the end of each session | Teacher or technician | Verify that benches and floors remain dry, spills are cleaned promptly, waste is segregated correctly, and contaminated materials are removed from the work area. |
| PPE compliance check | Each session | Teacher | Confirm that required eye protection, gloves, lab coats or aprons, and closed-toe footwear are worn correctly and that damaged or contaminated PPE is replaced. |
| Periodic review of controls | Termly and after any incident or near miss | Science department lead or designated safety coordinator | Review incident reports, near misses, student feedback, and any changes to the experiment to confirm that controls remain effective and proportionate to the risk. |
9. Special Circumstances
- Higher temperatures within the 30°C to 60°C range increase the likelihood of burns, splashes, and glassware stress, so additional supervision and stricter handling controls are required as temperature rises.
- Night work or reduced-light conditions can make labeling, spill detection, and glassware inspection more difficult; improve lighting and supervision before starting the practical.
- Lone working should not be permitted for this practical because hot water, glassware, and chemical handling require immediate assistance in the event of a spill, burn, or breakage.
- Wet floors, crowded benches, or hurried movement increase slip and collision risk, especially when carrying hot beakers or transferring swatches.
- Students with skin sensitivity, visual impairment, or reduced dexterity may require additional controls, adapted equipment, or closer supervision.
Approval and Sign-off
This risk assessment has been reviewed and approved by:
Assessor: _________________________ Date: __________
Manager/Supervisor: _________________________ Date: __________
Safety Representative: _________________________ Date: __________
This risk assessment must be reviewed annually and after any incident, near miss, change in chemicals, equipment, or procedure or when significant changes occur.
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References
Page links are approximateOccupational Safety and Health Standards (OSHA 29 CFR 1910) - 1910.1450 App A - National Research Council Recommendations Concerning Chemical Hygiene in Laboratories (Non-Mandatory)
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Rules for the Administration of the Oregon Safe Employment Act (General Occupational Safety and Health, Division 2, OSHA Oregon)
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