About Risk Assessment

Sophia CHENG

3 Nov 2009

Discussion on Risk Assessment

Risk Assessment• An analysis of a practical activity to identify

hazards and to take precautions to minimise the risk

• Procedures:– Identifying hazards

(Materials / Procedures / Equipment)– Assessing how likely the hazard will

actually cause harm– Deciding what control measures to

reduce risk to acceptable level– Finding how to dispose of hazardous

residues

Discussion on Risk Assessment – Sample 1

Investigation: Self-heating packRisk Assessment

Hazardous substances being used or made, hazardous procedures equipment

Nature of the hazards Control measures and precautions

Emergency action to be taken in case of accident

Sources of information

Copper Sulphate respiratory tract, eye, skin irritant

wear protective gloves, ensure good ventilation

eyes: flush with clean water

skin: wash with soap and water

MSDS No: BSLBP

Zinc metal powder may form combustion dust concentrations in air

water reaction

keep in tightly closed container

store in a cool, dry area away from source of heat, moisture

inhalation: remove to flesh air

ingestion: vomiting immediately

MSDS No: Z0858

Iron filings cause irritation to eyes and respiratory tract

avoid dust formation and control ignition sources

skin contact: wash exposed area with soap and water

MSDS No: 17495

Calcium oxide causes severe irritation and burns to every area of contact (react with water)

keep in tightly closed container

store in cool, dry, ventilated area

do not induce vomiting give large quantities of water or milk if available

MSDS No: C0462

Opinion on Sample 1 from Teacher A

Response to Risk Assessment – Sample 1

Investigation: Self-heating packRisk Assessment

Hazardous substances being used or made, hazardous procedures equipment

Nature of the hazards Control measures and precautions

Emergency action to be taken in case of accident

Sources of information

Copper Sulphate respiratory tract, eye, skin irritant

wear protective gloves, ensure good ventilation

eyes: flush with clean water

skin: wash with soap and water

MSDS No: BSLBP

Zinc metal powder may form combustion dust concentrations in air

water reaction

keep in tightly closed container

store in a cool, dry area away from source of heat, moisture

inhalation: remove to flesh air

ingestion: vomiting immediately

MSDS No: Z0858

Iron filings cause irritation to eyes and respiratory tract

avoid dust formation and control ignition sources

skin contact: wash exposed area with soap and water

MSDS No: 17495

Calcium oxide causes severe irritation and burns to every area of contact (react with water)

keep in tightly closed container

store in cool, dry, ventilated area

do not induce vomiting give large quantities of water or milk if available

MSDS No: C0462

Safety information about chemicals

• Material Safety Data Sheet (MSDS); CityU• http://cd1.edb.hkedcity.net/cd/science/laborat

ory/safety/msds_ss_2000.pdf

• International Chemical Safety Cards; ILO• http://www.ilo.org/public/english/protection/safe

work/cis/products/icsc/dtasht/index.htm

Hierarchy of Controls

Order Control Example

1 Eliminate Removing the hazard, e.g. taking a hazardous piece of equipment out of service

2 Substitute Replacing a hazardous substance or process with a less hazardous one

3 Isolate Isolating the hazard from the person at risk, e.g. using a guard or barrier

4 Engineer Redesign an experiment, piece of equipment or process to make it less hazardous

5 Administrative Adopt safe work practices. Provide appropriate training, instruction or information

6 Personal Protective Equipment

Use of lab-coat, gloves, safety glasses, safety footwear, dust masks, face shields, goggles, etc.

Another Example of Risk Assessment Form (1)Risk assessment form

Title of the experiment / task

Hazard identification – Equipment used & experimental design

(Consider what hazards are posed by, both the equipment and the experimental procedures. What harm can happen to people or equipment?)

Hazard identification – Materials

Hazard(s): tick if applicable

Hazardous substanceReactants / Products

Flammable Toxic Corrosive Harmful Irritant Oxidising Other(Please detail)

Control adopted for risk minimization

Flammable chemicalVolume: small / med. / large□ No ignition sources□ Use in fumehood□ Temp. of reaction controlled at _____ oC□ Other: ____________

Toxic chemical□ Use in fumehood□ Minimize the amount to ________ g/cm3

□ Wear personal protective equipment: ________________________________□ Other: _____________

Corrosive chemical□ Use in fumehood□ Minimize the amount to ________ g/cm3

□ Use more dilute chemical of ______ mol/dm3

□ Wear personal protective equipment: _____________□ Other: _____________

Oxidising chemical□ Use in fumehood□ Avoid contact with organic chemicals, reactive metals or metal powders□ Keep away from flammable substances□ Other: ______________

Chronic health□ Perform experiment in fumehood□ Operator awareness□ Avoid if allergic reaction develops□ Other: ___________

Another Example of Risk Assessment Form (2)Hazard identification – Materials

Hazard(s): tick if applicable

Hazardous substanceReactants / Products

Flammable Toxic Corrosive Harmful Irritant Oxidising Other(Please detail)

Another Example of Risk Assessment Form (3)Control adopted for risk minimization

Flammable chemicalVolume: small / med. / large□ No ignition sources□ Use in fumehood□ Temp. of reaction controlled at ____ oC□ Other: ____________

Toxic chemical□ Use in fumehood□ Minimize the amount to ___ g/cm3

□ Wear personal protective equipment: ________________________________□ Other: _____________

Corrosive chemical□ Use in fumehood□ Minimize the amount to ___ g/cm3

□ Use more dilute chemical of ______ mol/dm3

□ Wear personal protective equipment: _____________□ Other: _____________

Oxidising chemical□ Use in fumehood□ Avoid contact with organic chemicals, reactive metals or metal powders□ Keep away from flammable substances□ Other: ______________

Chronic health□ Perform experiment in fumehood□ Operator awareness□ Avoid if allergic reaction develops□ Other: ___________

Another Example of Risk Assessment Form (4)Further risk control measures

(List any control measures implemented, which are not listed above.)(Review the current controls using the Hierarchy of Controls: )

OrderControl Example

1 Eliminate Removing the hazard, e.g. taking a hazardous piece of equipment out of service

2 Substitute Replacing a hazardous substance or process with a less hazardous one

3 Isolate Isolating the hazard from the person at risk, e.g. using a guard or barrier

4 Engineer Redesign an experiment, piece of equipment or process to make it less hazardous

5 Administrative Adopt safe work practices. Provide appropriate training, instruction or information

6 Personal Protective Equipment

Use of lab-coat, gloves, safety glasses, safety footwear, dust masks, face shields, goggles, etc.

Another Example of Risk Assessment Form (5)

Source(s) of information

Disposal of residues

Example of Risk Assessment - Volhard Method (1)

Example of Risk Assessment - Volhard Method (2)

Example of Risk Assessment - Volhard Method (3)

Example of Risk Assessment - Volhard Method (4)

Thank You!