Laboratory Safety

Chemicals can enter the body by breathing, through the skin, eating, and injection. Inhalation (breathing in vapours or particulates) is the most common way that chemicals enter the body. Chemical exposure to the skin or eyes is another way that chemicals can get absorbed through the skin and into the bloodstream. Unintentional ingestion of chemicals can occur if food, drink, or our hands are contaminated. For this reason, food and drinks are not allowed inside a laboratory, and employees should wash their hands before eating. Finally, an injection may occur through sharp injuries or punctures to the skin.

The safety data sheet for each hazardous product in the laboratory must be reviewed before storing, handling, or using the product. It is important to note any incompatible products or safety measures before using the chemical. Some products require additional precautions including perchloric acid, picric acid, peroxide-forming compounds, and cryogenic liquids.

Through exhaust ventilation, guarding, safe work practices, and personal protective measures, employers can protect the health and safety of laboratory workers.

General

As an employer, you must make sure that:

• Written safe work procedures for hazardous operations, including spill response are established.
• Employees are instructed and trained in the safe work procedures for hazardous operations, and that they follow the safe work procedures.
• Suitable fire extinguishers are accessible in a laboratory where flammable substances are used or stored.
• When a container of hazardous substances is moved that it is not damaged.
• Personal protection
• Protective clothing is worn in a laboratory where hazardous substances are handled. The protective clothing must not be worn outside the work area and must not be stored in a way that employees may be exposed to hazardous substances.
• Eating and drinking are not allowed in the laboratory.
• Food is not kept in the laboratory, except if required for testing.
• Laboratory glassware, vessels, and containers are not used to prepare or store food or drinks for consumption.
• Hazardous substances are not pipetted by mouth.
• A safe means of handling sharp materials such as needles, knives, scissors, scalpels, or broken glass is used.
• Needles are not recapped before disposal unless the recapping device is designed for single-handed use or is otherwise safe for use.
• Biohazard sharp puncture-resistant containers are used to dispose of the sharp materials.

Laboratory fume hoods

A laboratory fume hood is an enclosed and mechanically ventilated workspace that is designed to draw air into the workspace and preventing or minimizing the escape of air contaminants out of the workspace. The employee can conduct physical, chemical, and biological manipulations inside the workspace through the operational face opening.

As an employer, you must make sure that:

• A laboratory fume hood installed on or after commencement of this section is selected, used, tested, and maintained in accordance with the CSA Standard Z316.5-20 “Fume hoods and associated exhaust systems”, or a standard that meets or exceeds this protection.
• The laboratory fume hood must also meet the requirements of Clause 10.3 of CSA Z316.5-20.
• A laboratory fume hood is connected to a local exhaust ventilation system and has an average face velocity of 0.4 m/s to 0.6 m/s across its operational face opening. The face velocity must not be 80% lower than the average or 120% higher than the average at any point across its operational face opening.
• A laboratory fume hood has a sash that is positioned to protect the upper body and face of an employee who is working at the fume hood from unintentional release of contents while allowing hand and arm access to the equipment inside the hood.
• A laboratory fume hood with a sash is clearly marked to identify the minimum and maximum size of its operational face opening.
• A commercially manufactured laboratory fume hood is certified as being tested by the manufacturer following installation and before it is first used.
• A custom-built laboratory fume hood is tested on-site by a competent person following installation and before it is first used.
• Laboratory fume hood tests demonstrate containment of the control level of 0.05 ppm or less when tested under “as manufactured” test conditions in accordance with ANSI/ASHRAE Standard 110-1995, Method of Testing Performance of Laboratory Fume Hoods or a standard offering equal or greater protection.
• An engineer certifies the installation of a laboratory fume hood.
• A laboratory fume hood is placed so that it prevents cross drafts or other disruptive forces from lowering the face velocity to an unacceptable level.
• A laboratory fume hood and its ductwork must be constructed from compatible materials for its use.
• Safety procedures are established, and employees are instructed and trained on the safe use and operation of a laboratory fume hood.
• Any laboratory fume hood that will be used for working with radioactive material in amounts that exceed the exemption quantity or perchloric acid is clearly labelled with the applicable restrictions on its use.
• A laboratory fume hood is not used for the storage of chemicals unless it is only used for that purpose and labelled with this limitation.
• Controls used to operate a laboratory fume hood and its service fixtures are located on the outside of the fume hood and within reach of an employee conducting work in the fume hood.
• The main shutoff valve for water taps located inside the fume hood is on the outside of the laboratory fume hood.
• Any equipment used in the laboratory fume hood is at least 15 cm from the operational face opening and does not negatively impact airflow in the fume hood.

Monitoring:

1. Face velocities across the operational face opening are quantitatively measured and the results documented.
2. The capability of a laboratory fume hood to contain air contaminants and maintain an inward flow is assessed using a smoke tube or other qualitative method and the results documented.
3. These measurements and assessments are performed after installation and before first use, at least once per year after installation, and after any repair or maintenance that may affect the face velocity.
4. Airflow in a laboratory fume hood is monitored continuously if the loss of airflow would lead to a risk to the health and safety of an employee.
5. A laboratory fume hood has an alarm that indicates when the average face velocity falls below the minimum average face velocity when the fume hood is in use.

• If following conditions are met laboratory fume hoods may be connected through a manifolded exhaust system:
1. section 5.3.2 of ANSI/AIHA Standard Z9.5-2003 Laboratory Ventilation or a standard that meets or exceeds these requirements,
2. hazard control measures installed to prevent backdrafts or pressure imbalances between rooms, and
3. an engineer must certify the ventilation design and installation of the manifolded exhaust system.
• Fume hoods used for radioactive materials or perchloric acid must not be connected to a manifolded exhaust system.
• The ducting used in the installation of a laboratory fume hood is designed using good engineering practices.

Laboratory equipment

As an employer, you must make sure that: 

• Any limitations of a biological safety cabinet are clearly posted and followed by employees.
• Biological safety cabinets are certified at least once a year by a competent person. A competent person must also certify biological safety cabinets before they are used after the initial installation, after a change of the HEPA filter, after moving the cabinet, and after any repair or maintenance that could affect the seal of the HEPA filter.
• The certification procedures meet the requirements of NSF/ANSI Standard 49-2002, Class II (Laminar Flow) Biosafety Cabinetry or a standard offering the same or better protection.
• Certification records are maintained and made available to an officer on request. Exhaust air from a biological safety cabinet is not recirculated when volatile toxic materials, flammable liquids, or gases are used in the cabinet, or when radioactive materials are used in amounts that exceed the exemption quantity.
• Biological safety cabinets used for handling biological agents are operated and ventilated in accordance with the Laboratory Biosafety Guidelines issued by Health Canada or a standard offering the same or better protection.

Centrifuge

• Centrifuge loads are balanced by sample distribution as required by manufacturer specifications.
• The centrifuge is equipped with aerosol-proof safety heads, cups, or other equally effective means to prevent exposure to biohazardous aerosols, carcinogens, and radioactive samples.
• Rotors are stored in a way that prevents them from being damaged.
• Centrifuge doors are interlocked if purchased on or after September 1, 2025, or if exempted by CSA Standard C22.2 No. 151-M1986 (R2004) Laboratory Equipment to prevent employees from accessing spinning rotors. The interlock must prevent the centrifuge door from opening while the rotor is spinning or causes the rotor to brake if the door is open.

While the employer is ultimately responsible for all the provisions mentioned above, the supervisor has a vital role to play in the safety of their teams. As a supervisor, you must:

• Acquaint your employees with the hazards and control measures associated with their work.
• Provide the information and instruction necessary to ensure their health and safety.
• Enforce company safety rules, programs, codes of practice and procedures, including ensuring employees comply with the requirements below.

Special chemical requirements

Certain chemicals have additional requirements for laboratory use. These chemicals include perchloric acid, picric acid, peroxide-forming compounds, and cryogenic liquids.

As an employer, you must make sure that:

Perchloric Acid

• Perchloric acid is used in a laboratory fume hood designed only for its use.
• Signs must be posted outside of the fume hood indicating that the fume hood is designed for perchloric acid use and the use or storage of combustibles in the fume hood is not allowed.
• The exhaust ducts of a fume hood designed for perchloric acid are as short as possible and routed directly outdoors. There must not be any interconnections to other exhaust ducts and the exhaust duct must be equipped with washdown facilities.
• Perchloric acid containers are stored so that in the event of a leak, the acid will not contact flammable materials, wood, or similar combustible materials.
• Stored perchloric acid is inspected monthly. If any discolouration is noted, the perchloric acid must be disposed of immediately in a safe manner.
• Anhydrous perchloric acid is only used if it is freshly made. Any unused anhydrous perchloric acid must be disposed of in a safe manner at the end of the procedure or the end of the day, whichever is first.

Picric Acid

• Solid picric acid is stored with at least 10% moisture content, and regular inspections are conducted to make sure that the minimum moisture content is maintained.
• Picric acid solution does not accumulate and dry around cap threads.
• A competent employee safely handles and disposes of picric acid that is suspected to be in an unacceptable condition.

Peroxide-forming compounds

• Peroxide-forming compounds are inspected and tested for peroxides as required by the supplier after the container is opened.
• Written records of the tests are maintained and are provided to an officer on request.
• A competent employee disposes or chemically treats compounds contaminated with peroxide materials to eliminate the peroxides.

Cryogenic Liquids

• Containers used for storage, transportation, and dispensing cryogenic liquids are designed for that purpose.
• Indoor dispensing stations and storage locations for cryogenic liquids are ventilated to prevent the build-up of harmful gases. To ensure the ventilation’s effectiveness, monitoring must be completed, and the results documented.
• Signs identifying the materials, hazards, and required precautions are posted on indoor dispensing stations and freezers with automatic filling cycles.

General Regulation - Occupational Health and Safety Act
N.B. Reg. 91-191

Part XX.1 LABORATORY SAFETY

Section 342.11 Compliance with CSA standard

342.11 (1) An employer shall ensure that a laboratory fume hood installed on or after the commencement of this section is selected, used, tested and maintained in accordance with CSA Standard Z316.5:20 "Fume hoods and associated exhaust systems" or a standard offering equivalent or better protection.

(2) An employer shall ensure that a laboratory fume hood installed before the commencement of this section meets the requirements of Clause 10.3 of CSA Standard Z316.5:20 "Fume hoods and associated exhaust systems" or a standard offering equivalent or better protection.

[N.B. Reg. 2022-79, s. 91]

Section 342.21 Sash

342.21 An employer shall ensure that a laboratory fume hood has a sash that is positioned to protect the upper body and face of an employee working in the laboratory fume hood from accidental releases of the contents of the hood while allowing hand and arm access to equipment inside the hood.

[N.B. Reg. 2022-79, s. 91]

Section 342.22 Operational face opening

342.22 An employer shall ensure that a laboratory fume hood with a sash is clearly marked to identify the minimum and maximum size of its operational face opening.

[N.B. Reg. 2022-79, s. 91]

Section 342.3 Testing

342.3 (1) With respect to testing, an employer shall ensure that

(a) in the case of a commercially manufactured laboratory fume hood, the fume hood is certified as being tested by the manufacturer following its installation but prior to its first use, and

(b) in the case of a custom-built laboratory fume hood, the fume hood is tested on site by a competent person following its installation but prior to its first use.

(2) A laboratory fume hood tested under subsection (1) shall demonstrate containment not greater than the control level of 0.05 ppm when tested under "as manufactured" test conditions in accordance with the methods described in ANSI/ASHRAE Standard 110-1995, "Method of Testing Performance of Laboratory Fume Hoods" or a standard offering equivalent or better protection.

[N.B. Reg. 2022-79, s. 91]

Section 342.31 Requirements

342.31 With respect to a laboratory fume hood, an employer shall ensure that

(a) the installation of the laboratory fume hood is certified by an engineer,

(b) the laboratory fume hood is placed in such a way as to prevent cross drafts or other disruptive forces from lowering the face velocity across its operational face opening to unacceptable levels, and

(c) the laboratory fume hood and its ductwork are constructed from materials compatible with their use.

[N.B. Reg. 2022-79, s. 91]

Section 342.32 Safety procedures

342.32 An employer shall ensure that safety procedures are established and employees are adequately instructed and trained in the safe use and operation of a laboratory fume hood.

[N.B. Reg. 2022-79, s. 91]

Section 342.4 Use of laboratory fume hoods

342.4 (1) An employer shall ensure that a laboratory fume hood that is or will be used for working with the following is clearly labelled with the applicable restrictions on its use:

(a) radioactive material in amounts that exceed the exemption quantity; or

(b) perchloric acid.

(2) An employer shall ensure that a laboratory fume hood is not used for storage of chemicals unless it is used exclusively for this purpose and is labelled with this limitation.

[N.B. Reg. 2022-79, s. 91]

Section 342.41 Controls

342.41 An employer shall ensure that the controls used to operate a laboratory fume hood and its service fixtures are located on the outside of the laboratory fume hood and within reach of an employee conducting work in the laboratory fume hood.

[N.B. Reg. 2022-79, s. 91]

Section 342.42 Water taps

342.42 Despite section 342.41, water taps may be located inside a laboratory fume hood if the main shutoff valve for the water is located outside the laboratory fume hood.

[N.B. Reg. 2022-79, s. 91]

Section 342.5 Equipment

342.5 An employer shall ensure that the equipment used in a laboratory fume hood is kept at least 15 cm from the operational face opening and is not adversely affecting airflow in the laboratory fume hood.

[N.B. Reg. 2022-79, s. 91]

Section 342.51 Airflow and containment monitoring

342.51 (1) An employer shall ensure that the face velocities across the operational face opening of a laboratory fume hood are quantitatively measured and the results of the measurement are documented.

(2) An employer shall ensure that the capability of a laboratory fume hood to contain air contaminants and maintain an inward flow of air across its operational face opening is assessed using a smoke tube or any other appropriate qualitative method of assessment and that the method used and the results of the assessment are documented.

(3) An employer shall ensure that the measurements and assessments referred to in subsections (1) and (2) are performed

(a) after the laboratory fume hood is installed and before it is first used,

(b) at least once in each 12-month period after installation, and

(c) after any repair or maintenance that could affect the face velocity across the operational face opening of the laboratory fume hood.

(4) An employer shall ensure that airflow in a laboratory fume hood is monitored continuously if loss of airflow will result in risk to the health or safety of an employee.

(5) An employer shall ensure that a laboratory fume hood is equipped with an alarm capable of indicating when the average face velocity falls below the minimum average face velocity required in paragraph 342.2(b) when the laboratory fume hood is in use.

[N.B. Reg. 2022-79, s. 91]

Section 342.52 Manifolded exhaust system

342.52 (1) Laboratory fume hoods may be connected to a manifolded exhaust system if the following conditions are satisfied:

(a) the requirements of section 5.3.2 of ANSI/AIHA Standard Z9.5-2003, "Laboratory Ventilation" or a standard offering equivalent or better protection are met;

(b) when the laboratory fume hoods are installed in more than one room, hazard control measures are installed to prevent backdrafts and pressure imbalances between rooms; and

(c) the ventilation design and installation of the manifolded exhaust system are certified by an engineer.

(2) Despite subsection (1), an employer shall ensure that laboratory fume hoods that are or will be used for working with the following are not connected to a manifolded exhaust system:

(a) radioactive materials in amounts that exceed the exemption quantity; or

(b) perchloric acid.

[N.B. Reg. 2022-79, s. 91]

Section 342.6 Ducting

342.6 An employer shall ensure that ducting used in the installation of a laboratory fume hood is designed in accordance with good engineering practices.

[N.B. Reg. 2022-79, s. 91]

Section 342.61 Biological safety cabinets

342.61 (1) An employer shall ensure that the limitations of a biological safety cabinet are clearly posted on the cabinet and followed by employees.

(2) An employer shall ensure that biological safety cabinets are certified by a competent person

(a) at least once a year, and

(b) before they are used following:

(i) the initial installation;

(ii) a change of the HEPA (high efficiency particulate air) filter;

(iii) the moving of the cabinet; and

(iv) any repair or maintenance that could affect the seal of the HEPA (high efficiency particulate air) filter.

(3) With respect to certification, an employer shall ensure that

(a) the certification procedures used by a competent person under subsection (2) meet the requirements of NSF/ANSI Standard 49-2002, "Class II (Laminar Flow) Biosafety Cabinetry" or a standard offering equivalent or better protection, and

(b) the certification records are maintained and made available to an officer on request.

(4) Recirculation of exhaust air into a work area from a biological safety cabinet is not permitted when volatile toxic materials or flammable liquids or gases are used in the cabinet, or when volatile radioactive materials are used in amounts that exceed the exemption quantity.

(5) Biological safety cabinets used for handling biological agents shall be operated and ventilated in accordance with the "Laboratory Biosafety Guidelines" issued and amended from time to time by Health Canada or a standard offering equivalent or better protection.

[N.B. Reg. 2022-79, s. 91]

Section 342.62 Centrifuges

342.62 (1) With respect to a centrifuge, an employer shall ensure that

(a) the centrifuge loads are balanced by sample distribution in accordance with manufacturer specifications,

(b) the centrifuge is equipped with aerosol-proof safety heads or cups or other equally effective means to prevent employees from being exposed to biohazardous aerosols, carcinogens and radioactive samples, and

(c) the rotors are stored in a manner which prevents them from being damaged.

(2) On or after September 1, 2025, an employer shall ensure that

(a) unless exempted by CSA Standard C22.2 No. 151-M1986 (R2009), "Laboratory Equipment" or a standard offering equivalent or better protection, the centrifuge door is interlocked to prevent employees from accessing spinning rotors, and

(b) the interlock referred to in paragraph (a) prevents the centrifuge door from opening while the rotor is spinning or causes the rotor to brake if the door is opened, or another equally effective means is used to prevent employees from accessing the spinning rotor.

[N.B. Reg. 2022-79, s. 91]

Section 342.7 Safety procedures - hazardous operations

342.7 With respect to hazardous operations, an employer shall ensure that

(a) written safe work procedures for hazardous operations, including spill response, are established,

(b) employees are adequately instructed and trained in the safe work procedures for hazardous operations, and

(c) employees follow the safe work procedures for hazardous operations.

[N.B. Reg. 2022-79, s. 91]

Section 342.71 Fire protection

342.71 An employer shall ensure that suitable fire extinguishers are accessible at all times in a laboratory where flammable substances are used or stored.

[N.B. Reg. 2022-79, s. 91]

Section 342.72 Movement of containers

342.72 An employer shall ensure that a container of hazardous substances that is moved within a laboratory is moved in a manner that does not damage the container.

[N.B. Reg. 2022-79, s. 91]

Section 342.8 Personal protection

342.8 With respect to the protection of employees, an employer shall ensure that

(a) protective clothing worn in a laboratory in which hazardous substances are handled is not worn outside the work area and is not stored in a manner or location in which employees may be exposed to the hazardous substances,

(b) eating and drinking are not permitted in the laboratory,

(c) food is not kept in the laboratory, except as required for testing,

(d) laboratory glassware, vessels and containers are not used to prepare or store food or beverages for consumption, and

(e) hazardous substances are not pipetted by mouth.

[N.B. Reg. 2022-79, s. 91]

Section 342.81 Perchloric Acid

342.81 With respect to the use of perchloric acid in a laboratory fume hood, an employer shall ensure that

(a) perchloric acid is used in a laboratory fume hood designed exclusively for its use,

(b) signs are posted outside the laboratory fume hood indicating

(i) that the fume hood is designed for perchloric acid use, and

(ii) that the use or storage of combustibles in the laboratory fume hood is prohibited,

(c) the exhaust ducts of a laboratory fume hood are as short as possible, routed directly outdoors with no interconnections to other exhaust ducts and equipped with washdown facilities,

(d) containers of perchloric acid are stored in such a manner that, in the event of a leak, the spilled acid will not come in contact with flammable materials, wood or similar combustible materials,

(e) the stored perchloric acid is inspected at least once a month and, if any discolouration is noted, the perchloric acid is disposed of immediately in a safe manner, and

(f) anhydrous perchloric acid is used only if it is freshly made and any unused anhydrous perchloric acid is disposed of in a safe manner either at the end of the experiment or procedure or the end of the day, whichever occurs first.

[N.B. Reg. 2022-79, s. 91]

Section 342.82 Picric Acid

342.82 With respect to picric acid, an employer shall ensure that

(a) solid picric acid is stored with at least 10% moisture content,

(b) regular inspections are conducted to ensure that the minimum moisture content is maintained,

(c) picric acid solution does not accumulate and dry around cap threads, and

(d) picric acid that is suspected of being in an unacceptable condition is safely handled and disposed of by a competent employee.

[N.B. Reg. 2022-79, s. 91]

Section 342.9 Peroxide-forming compounds

342.9 With respect to peroxide-forming compounds, an employer shall ensure that

(a) peroxide-forming compounds are inspected and tested for peroxides as required by the supplier after the container is first opened,

(b) written records of the tests are maintained and made available to an officer on request, and

(c) compounds contaminated with peroxide materials are disposed of by a competent employee or are treated chemically to eliminate the peroxides.

[N.B. Reg. 2022-79, s. 91]

Section 342.91 Cryogenic liquids

342.91 With respect to cryogenic liquids, an employer shall ensure that

(a) containers used for the storage, transportation and dispensing of cryogenic liquids are designed for that purpose,

(b) indoor dispensing stations and storage locations for cryogenic liquids are adequately ventilated to prevent the development of harmful atmospheres,

(c) monitoring is performed to ensure the effectiveness of the ventilation of indoor dispensing stations and storage locations for cryogenic liquids and the results are documented, and

(d) signs are posted on indoor dispensing stations and freezers with automatic filling cycles for cryogenic liquids identifying the materials, the hazards and the precautions required.

[N.B. Reg. 2022-79, s. 91]

Section 342.92 Sharp materials

342.92 With respect to sharp materials, an employer shall ensure that

(a) safe means of handling needles, knives, scissors, scalpels, broken glass and other sharp materials are used,

(b) recapping of needles before disposal is not permitted unless the recapping device is specifically designed for single-handed use, or is otherwise safe for use, and

(c) biohazard sharp puncture-resistant containers are used for the disposal of needles, knives, scissors, scalpels, broken glass and other sharp materials to prevent the possibility of cuts or puncture.

[N.B. Reg. 2022-79, s. 91]