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Chemical safety program

Chemical safety program

Chemical safety has many scientific and technical components. Certain chemicals can be harmful to our health and environment, it is therefore important to ensure the safe management of chemical materials for use, disposal, storage, acquisition, inventory control, and regulatory compliance.

EHS personnel provides training and advice to faculty, staff and students in ensuring safe chemical practices. Our goal is to improve chemical users knowledge of chemical safety and to ensure regulatory compliance.

For more information refer to the chemical safety policy, procedures, guidelines, forms and manuals. If you require more information contact  Environmental Health & Safety at ext. 4877.

WHMIS stands for Workplace Hazardous Materials Information System. It is a Canadian system implemented in 1988, ensuring worker protection through education and prevention. The objectives of the program are to train employees in order to:

  • protect themselves from hazards
  • respond to emergency situations

It also implements standardized labeling of controlled products and makes materials safety data sheets (MSDSs) available. A Controlled Product is the name given to products, materials, and substances that are regulated by WHMIS legislation.

WHMIS is governed by federal and provincial laws and regulations. The majority of the "information" requirements (and exemptions) of WHMIS legislation are under the Hazardous Products Act and the Hazardous Materials Information Review Act and apply to all of Canada. In Quebec, the CNESST is responsible for applying WHMIS according to the regulations. Any person supplying or using controlled products must comply with it.

As such, staff and students that work with, or may be exposed to, hazardous materials must be trained according to WHMIS legislation in the following aspects:

  • Education –understanding the principles of WHMIS, and the meaning of the information on labels and MSDSs
  • Training – workplace-specific training on how to apply this information to materials in actual use in the workplace, including: procedures for storage, handling, disposal, and personal protection.

EHS provides WHMIS trainings for the staff and students at both Concordia campuses.  Please check the following link to get more details about WHMIS training offered at Concordia:

EHS provides WHMIS trainings for the staff and students at both Concordia campuses. 

WHMIS Classification

WHMIS divides hazardous materials into six main classes based on their specific hazards.  If a product corresponds to one or more of these classes, it becomes a « controlled » product.


When a supplier produces or imports a product for distribution and sale in Canada, that supplier must prepare a supplier label, which will typically provide seven pieces of information:

  • product identification;
  • hazard symbols representing the classes and divisions into which the product falls;
  • risk phrases;
  • precautionary statements;
  • first aid measures;
  • a statement advising that a material safety data sheet (MSDS) is available;
  • supplier's identification.

Furthermore, the text must be in English and French and contained within a hatched boarder.

Workplace labels are required on containers of controlled products produced on site and on containers in which the product has been transferred from a supplier's container. Workplace labels must provide three types of information:

  • product name
  • safe handling information
  • reference to the MSDS
  • in Quebec, according to the legislation, the minimum language requirement for workplace labels is French.  However, Concordia University being an English-teaching institution, workplace labels should be written at least in English, a language understood by everyone working and studying at Concordia University.

The label requirements for reagents prepared in the laboratory are the following:

  • Product name and concentration
  • Abbreviations NOT permitted
  • In certain cases (e.g. peroxidizable reagents), the date of purchase or preparation of the reagent

Additional requirements also include that:

  • the MSDS must be available
  • the chemical is not to be transported out of the laboratory.

Consumer Restricted Products

If a consumer can buy a chemical product in Canada through a retail store/outlet network, then that product must meet the requirements of the Consumer Chemicals and Containers Regulations, 2001 (CCCR, 2001), issued under the Hazardous Products Act (HPA). Since these consumer products are available to the public in retail stores, they are partially exempt from the labeling and MSDS requirements of WHMIS. However, if these products are brought and used at the workplace, they must be included within the WHMIS training requirements and must also follow the WHMIS workplace label requirements.

EHS highly recommends having MSDS copies available to workers handling chemicals covered under the Consumer Chemicals and Containers Regulations within their regular daily duties.

For more information concerning Consumer Products, please refer to the following link:

Consumer Chemicals and Containers Regulations - Health Canada

The Globally Harmonized System of Classification and Labelling of Chemicals (GHS) was adopted by the UN Economic and Social Council (ECOSOC) in July 2003. The purpose is to regroup all existing hazard communication systems on chemicals in order to develop a single, globally harmonized system to address classification of chemicals according to their hazards and communicate the related information through labels and safety data sheets.

In 2015, the Government of Canada published the Hazardous Products Regulations (HPR), which modified the Workplace Hazardous Materials Information System (WHMIS) 1988 to incorporate the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) for workplace chemicals. This modified WHMIS is referred to as WHMIS 2015.There are new standardized::

  • classification rules and hazard classes based on:
    • physical hazards
    • health hazards
    • environment hazards (not proposed to be adopted in Canada under WHMIS)
  • format for Safety Data Sheets (SDSs) (formerly known Material Safety Data Sheets)
  • label requirements:
    • new hazard symbols/pictograms
    • signal words (Danger and Warning)
    • hazard statements
    • precautionary statements

Label Requirement

While WHMIS 2015  includes new harmonized criteria for hazard classification and requirements for labels and safety data sheets (SDS), the roles and responsibilities for suppliers, employers and workers have not changed.

For more information about WHMIS 2015, please refer to the following links:


Personal protective equipment (PPE) is necessary to work with most hazardous materials and/or to perform certain experiments. It is a last resort protection system, to be used when substitution or engineering controls are not feasible.  It may also be necessary to supplement the safety equipment in laboratories such as the fume hoods.  PPE does not reduce or eliminate the hazard, protects only the wearer, and does not protect anyone else.

PPE includes gloves, eye protection, respiratory protection and protective clothing. The type of PPE required is highly dependent upon the nature of the experiment and the hazards associated with the material being used. However, the minimum requirements for any laboratory work done at Concordia University are the following:

  • safety glasses
  • lab coat
  • long-sleeved and long-legged clothing worn underneath the lab coat
  • closed shoes
Eye Protection

Safety Glasses

Wearing eye and face protection is necessary to protect against splashing chemicals, biological materials and flying particles. Eye protection in the form of glasses, goggles or face shields is available and the choice will depend on the risk involved with the experiment or the type of material being used.  The worker should consult the experiment SOP or the MSDS to choose the right type of protection in accordance with the CSA standard for Industrial Eye and Face Protectors Z94.3. The information in the Z94.3.1 “Protective Eyewear: A User's Guide” by Canadian Standards Association is also a good source of information or contact your supervisor or EHS.

Safety glasses must have side shields and must be worn whenever there is the possibility of objects striking the eye, such as particles, glass, or metal shards. Many potential eye injuries have been avoided by wearing safety glasses.  If prescription safety glasses are to be worn in the laboratory, they must be equipped with side-shields in order to provide appropriate protection. Regular prescription glasses are not considered safety glasses.  If regular prescription glasses are used, special safety glasses designed to fit over them must be worn.

However, safety glasses do not provide adequate protection against chemical splashes, aerosols or dusts/powders.  They do not seal to the face, resulting in gaps at the top, bottom and sides, where chemicals may seep through.  If such hazards are present in the laboratory work, goggles are best suited for this type of potential exposure.

Chemical Splash Goggles

Chemical splash goggles should be worn when there is potential for splash from a hazardous material, such as working with solvent and highly corrosive materials.  Chemical splash goggles should be impact resistant and have indirect ventilation so hazardous substances cannot drain into the eye area.  Some can even be worn over prescription glasses.

Face Shields

Face shields are to be used when working with large volumes of hazardous materials, such as highly corrosive substances, either for protection from splash to the face or flying particles. Face shields along do not provide sufficient eye protection; they must be used in conjunction with safety glasses or goggles.

Contact Lenses

  • Contact lenses may be worn in the laboratory, but do not offer any protection from chemical contact. Therefore, lab workers wearing contact lenses must comply with the same rules in terms of eye protection.
  • Lab workers should be aware of the following :
  • You should advise their supervisors.
  • You may have to remove lenses to perform certain experiments.
  • Plastic used for contact lenses is permeable to some vapours found in a laboratory. Such vapours can be trapped behind the lens and may cause extensive irritation to the eye.
  • If a contact lens becomes contaminated with a hazardous chemical, rinse the eye(s) using an eyewash station and remove the lens immediately.
  • Contact lenses that have been contaminated with a chemical must be discarded.

Protective Clothing

Lab coats are required in all laboratories. These are available in various designs and materials and the choice should depend on the type of work being done and the risks involved. The typical lab coat is a knee length cotton-blend with long sleeves and front closure.  Lab coats are appropriate for minor chemical splashes and solids contamination.

If highly toxic or corrosive liquids are to be used, rubber aprons and chemical smocks offer improved protection over regular lab coats. Disposable outer garments (i.e., Tyvek suits) may be useful when cleaning and decontamination of reusable clothing is difficult. Long-sleeved and long-legged clothing should be worn beneath the lab coat to protect the skin in case of a spill. For best protection a lab coats should be knee length, have long sleeves to the wrist and be buttoned up.  Shorts and skirts should not be worn when working in a laboratory. Contaminated lab coats should not be washed at home with other laundry. A cleaning service is provided by certain departments.


Closed-toed shoes should be worn at all times in laboratories where chemicals are stored or used.  Sandals, high heel shoes, canvas toed shoes, as well as open-toed and open-backed shoes should be avoided due to the danger of spillage of corrosive or irritating chemicals and broken glass. Chemical resistant overshoes or boots may be used to avoid possible exposure to corrosive chemical or large quantities of solvents or water that might penetrate normal footwear (e.g., during spill cleanup).


Skin contact is a potential source of chemical exposure.  Protective gloves should be used to prevent the potential exposure to chemicals or biological hazards.  The proper type of glove will depend on the materials being used.  The MSDS is an important source of information for proper glove selection.  Different glove types have different chemical permeability, therefore you can check with the manufacturer’s compatibility chart before choosing a specific glove type. Understanding the terms used in glove compatibility charts is primordial.

  • Breakthrough time: Time it takes for the chemical to travel through the glove material. This is only recorded at the detectable level on the inside surface of the glove.
  • Permeation Rate: Time it takes for the chemical to pass through the glove once breakthrough has occurred. This involves the absorption of the chemical into the glove material, migration of the chemical through the material, and then de-absorption once it is inside the glove.
  • Degradation rating: This is the physical change that will happen to the glove material as it is affected by the chemical.  This includes, but is not limited to, swelling, shrinking, hardening, cracking, etc. of the glove material.

Compatibility charts rating systems will vary by the manufacturer’s design of their chart. Many use a color code, where red = bad, yellow = not recommended, green = good, or some variation of this scheme. A letter code may be used, such as E + excellent, G = Good, P = poor, NR = Not Recommended. Any combination of these schemes may be used, so please understand the chart before making a decision on the glove to be used.

The following document includes major glove types and their general uses. This list is not exhaustive.

Gloves Types and Uses

Other Considerations

  • Level of dexterity: Where fine dexterity is crucial, a bulky glove may actually be more of a hazard. Thinner, lighter gloves offer better touch sensitivity and flexibility, but may provide shorter breakthrough times. Generally, doubling the thickness of the glove quadruples the breakthrough time.
  • Glove length: Should be chosen based on the depth to which the arm will be immersed or where chemical splash is likely. Gloves longer than 14 inches provide extra protection against splash or immersion.
  • Glove size: One size does not fit all. Gloves which are too tight tend to cause fatigue, while gloves which are too loose will have loose finger ends which make work more difficult. The circumference of the hand, measured in inches, is roughly equivalent to the reported glove size.
  • Glove care: All gloves should be inspected for signs of degradation or puncture before use. Disposable gloves should be changed when there is any sign of contamination.  Reusable gloves should be washed frequently if used for an extended period of time.


Latex gloves

The use of latex gloves has been associated with an increased sensitization and the development of allergy symptoms over the last decades. Such symptoms include skin rash and inflammation, respiratory irritation, asthma and shock.  The amount of exposure needed to sensitize an individual to natural rubber latex is not known, but when exposures are reduced, sensitization decreases.  Disposable latex gloves offer poor protection against chemicals and are not recommended to be used in the laboratory environment.  However, if latex gloves must be used, choose reduced-protein, powder-free latex gloves and wash hands with mild soap and water after removing latex gloves.


As research facilities have increasingly moved away from latex exam gloves because of their well-known allergy-related symptoms, other types of skin irritation and allergy to non-latex gloves have also increased. Some people can potentially develop an allergic contact dermatitis with the use of nitrile gloves, mainly caused by chemical accelerators used in the production of nitrile and other latex-free gloves. While vinyl gloves may be an option in some circumstances, they lack the elastic quality of nitrile and latex gloves, and do not provide the same level of protection. Alternative glove options are available from different suppliers against nitrile and latex allergies such as:

  • accelerator-free nitrile gloves
  • nitrile with aloe gloves, which are easier on the skin
  • cotton liners (for sweaty hands too): they put a barrier between the glove and the skin and also absorb some of the moisture, which can also give a rash
  • Neo-Pro gloves (Neoprene chloroprene)

Additional information about a controlled or hazardous substance is provided on its Material Safety Data Sheet (MSDS) or Safety Data Sheet (SDS). The term MSDS is used in the WHMIS 1988 legislation; it is now being replaced by the term SDS in the WHMIS 2015 legislation.  The MSDS/SDS is provided by the supplier with the initial product’s purchase to give users detailed information about the hazards and safe use of products. All MSDSs/SDSs must be accurate at the time of sale or import.

A MSDS/SDS mentions what the hazards of a product are, how to use the product safely, what to expect if the recommendations are not followed, how to recognize symptoms of exposure, and what to do if emergencies occur. Before using any product for the first time, students and staff should review the chemical’s MSDS/SDS for more information.

Most MSDSs/SDSs have now adopted the WHMIS 2015 format which divides the information into 16 sections (as opposed to the original 9-section format required by WHMIS 1988).

Information in a product MSDS should be presented as follows:

  1. Identification
  2. Hazard(s) identification
  3. Composition/information on ingredients
  4. First-aid measures
  5. Firefighting measures
  6. Accidental release measures
  7. Handling and storage
  8. Exposure controls/personal protection
  9. Physical and chemical properties
  10. Stability and reactivity
  11. Toxicological information
  12. Ecological information
  13. Disposal considerations
  14. Transport information
  15. Regulatory information
  16. Other information

MSDS/SDS copies should be available to anyone who come in contact with controlled or hazardous chemicals during their daily work. Employers must ensure the MSDS/SDS's provided to their employees are the most accurate (updated) copy available. All MSDS/SDS copies should be kept in a dedicated location for each specific work area (laboratory, workshop, etc.). Employers may also computerize the MSDS/SDS information as long as:

  • All employees have access are trained on how to use the computer or device;
  • The computer/device is kept in working order;
  • Ability to make a hard copy of the MSDS/SDS available to employees upon request.

Concordia University has a subscription to CHEMWATCH, a MSDS/SDS database, allowing anyone using a Concordia computer or wireless network to access MSDS/SDS data. A direct link to the CHEMWATCH database is available on the EHS webpage. A quick reference guide on how to access a MSDS/SDS from CHEMWATCH is available here.

Certain chemicals are more dangerous than others due to their reactivity or high toxicity.  Specific precautions must be taken, as well as following the laboratory safety procedures, when handling these reagents. Towards academic research safety, each department is required to develop specific Standard Operating Procedures (SOPs) for high-risk, chemical procedures where toxic, pyrophoric, water-reactive, self-reactive, or energetic materials are used. Should your activities involve any of the specific reagents referred in the following safety guidelines, including the ones related to Nanomaterials and Peroxide-Forming Reagents, please contact EHS for assistance in developing SOPs.

Although the use of metallic mercury is not prohibited at Concordia, EHS strongly suggests minimizing its usage. Mercury presents a health and safety hazard and has been recognized as a contaminant of the environment by Health Canada, Environment Canada and l’Institut national de santé publique du Québec. Lab users are most likely to encounter mercury in old laboratory equipment, such as thermometers, barometers or manometers. In the event of a mercury spill, special clean-up and disposal procedures must be followed.

EHS has therefore instituted a green exchange program to replace mercury-containing thermometers with less hazardous alternative models. This exchange program is only available to Concordia labs/studios/workshops. The non-mercury thermometers contain about 0.15 mL of different colored organic liquids which are less hazardous in the event of a spill. This safer, greener alternative does not compromise the quality or precision of measurements.

EHS can provide lab-grade replacement thermometers with temperature ranges from -20°C to 150°C and from -10°C to 260°C. If you have any mercury thermometers in your possession and wish to exchange them, please contact EHS at, mentioning how many thermometers you wish to exchange.  Please note this program is based on a 1 to 1 exchange; EHS will distribute replacement thermometers only to labs that provide mercury thermometers in exchange.

For higher temperature ranges, electronic thermometers can represent an interesting alternative to mercury as they can measure temperatures from -50°C to 300°C.  Most thermometers with mercury replacements (liquid or electronic) are unable to conduct temperature measurements above 300°C.  Therefore, other alternatives such as thermocouples should be considered.  Please note that these latest options are not available from EHS as part of the exchange program.

There are chemicals that have the possibility of developing peroxides over time. Organic peroxides are substances characterized by the R-O-O-R structure, where R represents organic radicals. The O-O bond of organic peroxides is unstable and can lead to spontaneous decomposition. These products are oxidant and unstable and can create fire and/or explosive hazards. Organic peroxides should be kept in refridgerators for better stability. Refer to the MSDS of the reagents to find the specific storage conditions.

All solvents and reagents that can form hazardous peroxides should be labeled once received and include the date and expiration date(s) (manufacturer's expiration date or "after reception" expiration date). It is the scientist’s responsibility to ensure the goods are received in this manner as well as the proper disposal of the solvents/reagents prior to the expiration date. Refer to the MSDS for guidance. Peroxide test strips can be purchased to assess the peroxide content of solvents/reagents that you are not certain of.

Quantofix® peroxides test sticks 1-100 mg/L Sigma-Aldrich

XploSens PS™ peroxides detection strips 

Peroxide-containing solvents or reagents should never be heated or concentrated in order to avoid  explosive hazards. There are different techniques available to remove peroxides from solvents or reagents. If the peroxides can not be removed contact EHS to discard. (Do not mix with other chemicals) 

Please, consult the Peroxide-Forming Chemicals Safety Guidelines for more information.

Nanoparticle safety is an area where the safety research is just starting to catch up to the exciting research associated with new discoveries and applications.

Safety in an area where there are a great many unknowns and little to no regulation has to be handled in such a way that the known hazards are mitigated accordingly and the toxicity, especially unknown toxic effects are mitigated by exposure protection means.

Environmental Health & Safety (EHS) has created guidelines concerning the use of nanoparticles within laboratory facilities. These guidelines provide information about the properties of commonly used nanoparticles/nanomaterials, their health and safety hazards and ways to protect oneself from potential laboratory exposure. A training session on “Safe Handling of Nanomaterials” offered by EHS.  Register on-line in the Safety Training section of the EHS webpage.

Nanomaterial Safety Guidelines

Certain chemicals that may be used to produce reactive materials are defined as Restricted Component . The following SOP describes the requirements to acquire such material.


Hazardous materials are the responsibility of all those involved in the life cycle of the materials, from the beginning until the end. The goal of the University is to ensure that individuals working in areas where hazardous materials are used or stored are regularly informed and updated about risks, and  avoid the acquisition of unnecessary stock.  Keeping an inventory of hazardous materials is necessary to know what materials  are already present in a laboratory and what is required.  The inventory technician barcodes all hazardous materials and enters them in Vertére.  Vertére is a website from HECHMET (Higher Education Co-operative for Hazardous Materials and Equipment Tracking). The EHS inventory technicians perform on-site updates to every laboratories inventory on demand. The inventory technicians enter new hazardous material into the database, scan all barcodes on existing bottles and containers, and remove consumed, missing or relocated materials from the database. Once the inventory process is completed, the Principal Investigator (PI)  receives an updated list of their hazardous materials. All PI's are assigned a user name and password to view their chemical inventory in Vertére.

For questions or assistance please contact:

Loyola Sir George Williams
Contact name: Catherine Lévesque Christina St-Louis-Tulli
Office: PS-207 GM-1000-09
Phone number: 514-848-2424 ext.: 4353 8751

It is always preferable to refer to the MSDS for the storage requirements of individual chemicals.  However, as a general rule, it is preferable to separate the different chemical classes from each other:

  • flammable or combustible liquids
  • toxic chemicals
  • oxidizing agents
  • corrosive chemicals
  • compressed gases
  • water-reactive chemicals

They must be stored in a way which will not allow chemicals to mix with one another if a container breaks e.g. secondary containment. Chemicals should not be stored in fume hoods. If a fume hood needs to be used for chemical storage, it must be clearly indicated and cannot be used to run experiments. Always store and use the minimum quantity of chemicals that are necessary for the laboratory.

The following charts can be used for general guidelines in terms of storage compatibility.  You can also take a look at the Safe Storage of Hazardous Materials seminar on Moodle for a tutorial on how to safely store chemicals in your work area.  However, you should always consult the SDS for storage requirements of the specific material to verify its compatibility.

Simplified Chemical Compatibility Storage Guideline WHMIS 2015/WHMIS1988

Detailed Chemical Compatibility Chart

Acquisition, Use and Storage of Restricted Components

Flammable and combustible liquids:

  • Should be stored in a flammable storage (fire-resistant) cabinet
  • Cabinet should be vented from the bottom (with duct and joints also being fire resistant) or capped if not vented
  • No ignition sources should be present
  • Storage areas must be well-ventilated
  • Only one flammable storage cabinet per lab without prior approval
  • Should not be stored with oxidizers (e.g. ammonium nitrate, chromic acid, hydrogen peroxide, nitric acid, sodium peroxide and halogens)

Toxic chemicals:

  • Should be stored in a cool, dry, well-ventilated area, out of direct sunlight and away from heat
  • Always keep the smallest amount necessary in laboratory
  • Always consult the MSDS for storage requirements of the specific toxic material

Oxidizing agents:

  • Should always be stored separately from flammable materials, organic chemicals, dehydrating agents or reducing agents
  • Oxidizing agents should be stored in a fire-resistant, cool, and well-ventilated area

Corrosive chemicals:

  • Should be stored in a well-ventilated area to prevent a buildup of vapors and excessive corrosion
  • Should be stored in vented corrosion-resistant storage cabinets
  • Acids should be segregated from bases for storage
  • Secondary trays (polyethylene, Teflon, neoprene, or nitrile) should be used to contain any potential spill
  • Organic acids (e.g., glacial acetic acid) should be segregated from inorganic acids

Compressed gases:

  • Should be stored in a cool, dry area, away from flammable materials, ignition sources, excessive heat and potential sources of corrosion
  • Should be stored in storage cages when not used
  • Should be securely strapped or chained to a wall anchor or bench top to prevent falling when used
  • Cylinder cap should always be on whenever the cylinder is not in use
  • Oxygen cylinders should be stored separately from flammable gases
  • Flammable gases (e.g. propane) should be stored in a designated area or outside buildings
  • Should always use a cylinder cart to move cylinders around

Water-reactive chemicals:

  • Should be stored in a cool, dry, well-ventilated area, out of direct sunlight and away from heat
  • Should not be stored with flammable or combustible liquids
  • Should not be stored away from any source of moisture and preferably isolated by a waterproof barrier
  • Can be stored in desiccators


The spill of any hazardous materials can pose a significant safety or health hazard to persons in the immediate vicinity due to the properties of hazardous materials (toxicity, volatility, flammability, explosiveness, corrosiveness, etc.) or by the release itself (quantity, space considerations, ventilation, heat and ignition sources, etc.).  Therefore, it is imperative that each research group clearly establishes within their SOPs the types of spills that can safely be handled by lab personnel solely. EHS also provides a Minor Spill Response training upon request.  Please contact EHS at for more details concerning this training.

If laboratory staffs are to clean up a chemical spill, they must be sure to:

  • Stay within their comfort zone
  • Be familiar with the hazards of the materials
  • Have been trained or have clean-up instructions available on the MSDS or SOPs
  • Use appropriate PPE and necessary clean up equipment

For assistance, you may download: Typical Spill Kit

If the spill cannot be handled by lab personnel (e.g. large spill, highly toxic reagents, etc.), the staff should contact Campus Safety and Prevention Services using the following procedure:

  1. Advise and warn co-workers.
  2. Evacuate and secure the area immediately.
  3. Notify Campus Safety and Prevention Services at 3717 or 514 848-3717
  4. Provide the following information:
    • Your name and location of spill      
    • Name of hazardous material
    • Quantity involved
    • Related health risks and precautions to be taken
  5. Provide Material Safety Data Sheet (MSDS) or appropriate documentation.
  6. Assist the Campus Safety and Prevention Services personnel or the Chemical Spill Resource Person as required.

Any spill (large or small) involving hazardous material must be reported by filling up an incident report.  For more information concerning hazardous material spills, please visit:

Emergency procedure for Hazardous material incidents

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