Basic Safety Procedures

Section 6: Basic Safety Procedures

6.1 Procedures for Unattended Work

1. Unattended procedures should be kept to a minimum.
2. An unattended procedure must be visited periodically and a sign posted on the door of the lab outlining the procedure with the name and phone number of a contact person. The sign will indicate the date and time the procedure was started, when it is expected to be completed, and when it was last checked. (See Appendix 13)
3. Unattended procedures using cooling water must have the hoses securely attached and the water adjusted to the minimum flow necessary. Ensure plumbing drains are clear before leaving the procedure.

6.2 Working Alone

1. For safety reasons working alone should be avoided. Someone should always be within call when a laboratory procedure is being performed.
2. For work with hazardous materials or procedures the supervisor has the right to require that at least one other person be present.

6.3 Housekeeping

1. Work areas must be kept clean and free of obstructions.
2. Stairways and halls must not be used for storage. This applies to both equipment and personal property. Bicycles are not allowed in buildings.
3. Walkways and aisles in laboratories must be kept clear.
4. Access to emergency equipment or exits must never be blocked. (Ontario Regulation 851 Section123 (2))
5. Equipment and chemicals must be stored properly.
6. Spilled chemicals must be dealt with immediately and if safe cleaned up by the chemical user. (See Section 11.4 of this manual) Spills must be reported to the supervisor.
7. Wastes must be placed in appropriate, labeled containers.
8. Materials no longer used must not be allowed to accumulate and must be disposed of following proper procedures. (See Appendix 4, Disposal of Hazardous Waste)

6.4 Laboratory Equipment Maintenance

Laboratory equipment must be inspected and maintained by a qualified person. The frequency of the inspection depends on the hazard posed by the equipment, the manufacturer's instructions, or as required by regulations. Records of the maintenance must be kept on file by the laboratory supervisor and be available at all times.

6.5 Guarding

1. All mechanical equipment must be adequately guarded to prevent access to electrical connections or moving parts. (Ontario Regulation 851 Section 25)
   b) All centrifuges must be fitted with an interlock so that they cannot be accessed while moving or started while open. (Ontario Regulation 851 Section 31)

6.6 Shielding

1. Appropriate shielding must be used whenever an operation involves chemicals with the potential for explosion or severe splashing. Examples include:
   • when a reaction is attempted for the first time;
   • when a familiar reaction is carried out on a larger scale than usual;
   • whenever operations are carried out under non-ambient conditions; or
   • Whenever a severe splashing potential exists for corrosive materials. (Ontario Regulation 851 Section 89)
2. Shielding or equivalent precautions are to be used when working with non-ionizing radiation sources, magnetic and other fields. Examples include:
   • Lasers
   • Infrared radiation
   • Ultraviolet radiation
   • Microwave radiation
   Refer to the Radiation Safety Manual (available from EHSS) for shielding of ionizing radiation sources.
3. Appropriate shielding is required when using equipment with thermal hazards.

6.7 Glassware

1. Repair or dispose of any damaged glassware. Follow proper disposal procedures for damaged glassware. (See Appendix 4)
2. Ensure adequate hand protection is used when working with glass tubing.
3. Tape permanent vacuum glassware which presents an implosion risk with either electrical or duct tape or use appropriate shielding. (Ontario Regulation 851 Section 84 (b & f))
4. Wear appropriate hand protection when picking up broken glass.
5. Ensure proper instruction is given for the use of specialized glassware.
6. Specific procedures may apply for contaminated glassware.

6.8 Flammable and Combustible Material Hazards

1. Use an open flame only as long as necessary and extinguish it when done.
2. Do not use an open flame to heat flammable or combustible materials. It is generally not recommended to perform a distillation at reduced pressure using an open flame due to the possibility of local superheating.
3. Remove all flammable and combustible materials from the work area before lighting a flame.
4. Notify all others in the lab and note any procedure using flammable and combustible gases and liquids before lighting a flame.
5. Store all flammable and combustible materials properly as required by the Ontario Fire Code. (See Appendix 5, Storage and Handling of Flammable and Combustible Liquids)
6. Avoid open flames, use non-sparking equipment and adequate ventilation if a flammable atmosphere may be generated, for example when dispensing flammable or combustible solvents. (Ontario Regulation 851 Section 63)

6.9 Cryogenic Materials and Cold Traps

1. Wear proper gloves and a face shield when preparing or using a cold trap below –70 degrees C or cryogenic liquids.
2. Never use liquid nitrogen or liquid air as a cold trap to collect a flammable or combustible material mixed with air. Oxygen may condense from the air and lead to an explosion hazard.
3. Always ensure the flammable or combustible material is collected under vacuum. Use a Dewar vessel designed for cryogenic liquids not a regular domestic vacuum flask.
4. When returning the cooled material back to atmospheric pressure, ensure the cryogenic coolant has been removed to prevent liquid air condensation.
5. Use appropriate gloves when handling cryogenic materials, e.g. dry ice, etc.
6. Dry ice/solvent cooling baths should be prepared carefully by the slow addition of small amounts of the solid dry ice to the solvent to avoid excessive frothing and overflow of the solvent.
7. Never lower your head into a dry ice chest since a high level of CO2 may accumulate there posing an asphyxiation hazard.

6.10 Systems under Pressure

1. Never heat or carry out a reaction in a closed vessel unless it is designed or tested to withstand the expected pressure of the reaction.
2. Pressurized equipment must have an appropriate pressure release valve.
3. Pressurized equipment must be shielded, guarded, or designed to protect the operator against potential explosions.

6.11 Back Flow Preventers

1. All water faucets to which a hose is attached in a laboratory must be equipped with an appropriate backflow preventer. (Ontario Building Code) This prevents the contamination of the drinking water system. Contact the Manager, Maintenance Services at extension
2. 8821 for an evaluation.

6.12 Electrical Equipment and Apparatus

1. All electrical installations must conform to the provisions of the Power Commission Act of Ontario.
2. All electrical equipment must be CSA approved or inspected by Ontario Hydro.
3. Extension cords must not be used for permanent installations. Contact Physical Plant at 3668 to install or relocate outlets in close proximity to the equipment.
4. Use ground fault circuit interrupters where there is a risk of an operator coming in contact with water and electrical equipment simultaneously.
5. Only trained, qualified personnel may repair or modify electrical or electronic equipment.
6. Power bars should not be located beneath work benches where chemicals are handled.

6.13 Compressed Gas Cylinders

All compressed gases have potential health and safety hazards related to the chemical properties of the gas, as well as pressure hazards. Take precautions to protect personnel from these potential hazards

1. All gas cylinders, empty or full, must be properly secured so they cannot be knocked over. Cylinders with safety caps in place may be secured together. All others must be secured separately. (Ontario Regulation 851 Section 49)
2. Compressed gas cylinders should be transported capped and chained on appropriate carts.
3. Always wear eye protection when working with compressed gases.
4. Always use the appropriate regulator for the gas being used. The regulator should be inspected each time before use, as recommended by the manufacturer.
   Note: Failure of either the diaphragm or the regulator can occur unexpectedly. Be prepared. When opening the main valve of a compressed gas cylinder do not stand over the main valve or behind or in front of the pressure gauge(s). These are the most probable locations for failure.
5. Ensure the tubing and the apparatus downstream from the regulator are designed to withstand the pressures intended to be delivered. The tubing and other components should also be chemically resistant to the gas being used.
6. Never use PTFE (Teflon) tape, other lubricants or sealant when installing a regulator. The recommendation of commercial gas suppliers is that regulator fittings in good condition do not require additional sealants.
7. Ensure all installations are designed to prevent the hazardous combination of gases except as required by the use.
8. Take appropriate precautions to prevent exposure of yourself or others to the other hazardous properties of the gas used. Consult the safety data sheet.
9. Compressed gas cylinders have a finite shelf life. Ensure cylinders are regularly inspected. Any cylinder that is corroded or has damaged valve components should be returned to the supplier. All cylinders older than ten years should be returned to the manufacturer. Manufacturers of corrosive gases recommend that cylinders of corrosives be replaced every six months to guard against valve failure.

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