OFM - TG-01-2011: Handling Flammable and Combustible Liquids in School Laboratories

OFM Guideline

Office of the Fire Marshal

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OFM-TG-01-2011
Handling Flammable and Combustible Liquids in School Laboratories

 

March 2011

 

Acknowledgements  

The Office of the Fire Marshal would like to acknowledge the contribution of the following organizations in the development of this guideline:  

Office of the Fire Marshal

Fire Safety Standards Section

Applied Research Section

Fire Investigations Section

Media and Public Relations Section

Ontario Fire College

Dufferin-Peel Catholic District School Board

Ministry of Education - Curriculum and Assessment Policy Branch

Science Teachers’ Association of Ontario

Ministry of Labour

Ontario Municipal Fire Prevention Officers Association

Ontario Association of Fire Chiefs  

TABLE OF CONTENTS

SECTION

Abstract

1.0 SCOPE

2.0 LEGISLATION

3.0 HANDLING FLAMMABLE AND COMBUSTIBLE LIQUIDS

3.1 Science Instructor
3.2 Procedures

4.0  DEMONSTRATION OF INCOMPLETE AND COMPLETE COMBUSTION REACTIONS

4.1 Background Information
4.2 General Demonstration Description
4.3 Demonstration Details
4.4 Demonstration Procedures

4.4.1. General Safety Requirements
4.4.2. Incomplete Combustion
4.4.3. Complete Combustion

4.5 Demonstration Results

5.0 REFERENCES

 

February 2011
OFM Section: Fire Safety Standards at (416) 325-3100
The reproduction of this guideline for non-commercial purposes is permitted and encouraged. Permission to reproduce the guideline for commercial purposes must be obtained from the Office of the Fire Marshal, Ontario.


Abstract

The Ontario School Curriculum for Grade 11 and 12 outlines expectations that explore the understanding of the safety needed when handling flammable and combustible liquids.  

Where science instructors elect to conduct demonstrations using chemicals including flammable and combustible liquids, they need to be aware of legislation governing the use of these including those administered by the Ministry of Labour and Office of the Fire Marshal (Ministry of Community Safety and Correctional Services).  

It is expected that science instructors and students will be trained in safe procedures for handling chemicals including flammable and combustible liquids.  At a minimum, the science instructor must be trained in the Workplace Hazardous Materials Information System (WHMIS).  An annual review of the general procedures, as well as a review of specific experiment procedures prior to conducting an experiment is recommended.  Records of all training are recommended to be maintained.  

School Boards are responsible to ensure that science instructors and students have adequate training in handling flammable and combustible liquids.  This guideline may be used as the basis for this training and/or for the assessment of procedures.  

Compliance with this guideline does not preclude the requirement to meet the Fire Code in its entirety, nor with the requirement to meet all other applicable legislation including occupational health and safety requirements.
 

1.0 SCOPE

This guideline has been established to aid school board officials, science instructors and fire officials in the assessment of science classroom procedures for conducting demonstrations with flammable and combustible liquids.  

Sentence 4.12.4.1.(3), Division B of the Fire Code states:

"Personnel working in laboratories shall be trained in the safe handling of flammable and combustible liquids"

The Sentence prohibits school personnel from conducting demonstrations using flammable and combustible liquids unless they have been appropriately trained in the safe handling of them.  “Personnel” may be considered to include anyone actively handling flammable and combustible liquids, and may include instructors, demonstrators and students.  Throughout the guideline, the term instructor should be considered to include instructors, demonstrators or any individual actively participating in the handling of flammable and combustible liquids.

Training should include WHMIS training, and:

  • An awareness of how to read Material Safety Data Sheet (MSDS) records for any flammable and combustible liquids to be used in the laboratory
  • An appreciation that MSDS information must be adhered to
  • Awareness of appropriate demonstration equipment, and protective clothing
  • Awareness of the need to have appropriate extinguishing equipment nearby
  • Training in the use of classroom extinguishing equipment
  • Training in the implementation of the facility’s approved Fire Safety Plan
  • School Board procedures established detailing each demonstration where flammable and combustible liquids will be used
  • Ensuring that students are made aware of the risks of handling flammable and combustible liquids

This guideline provides procedures that must be used in conducting demonstrations using flammable and combustible liquids in Ontario classrooms.  Procedures specific to methanol demonstration are also provided, however this is for information purposes only and not intended to imply that this is a required demonstration.

The School Board is responsible for developing appropriate training which may include utilizing this Guideline, and ensuring that anyone using flammable and combustible liquids have received training prior to conducting any related demonstrations.  Re-training should be on a schedule to be determined by the School Board. 

Science instructors/demonstrators are responsible for reviewing demonstration procedures involving flammable and combustible liquids fully prior to conducting any demonstrations.  The procedures should also be reviewed with the students.
 

2.0 LEGISLATION

2.1  Ontario Fire Code

The Ontario Fire Code requires emergency planning procedures for schools in Section 2.8.  In addition to this, Sentence 4.12.4.1.(3) Division B, requires that:

"Personnel working in laboratories shall be trained in the safe handling of flammable and combustible liquids"

2.2 Occupational Health and Safety Act

Science instructors/demonstrators should have adequate training in the procedures for the safe use and handling of all chemicals used in the curriculum including flammable and combustible liquids.  School Boards should ensure as one of their duties under Section 25 of the Occupational Health and Safety Act (OHSA), that science instructors/demonstrators have the required training in chemical hazards that are part of the curriculum they are teaching.  The OHSA also requires that training and instruction provided to workers (in this case instructors/demonstrators) be reviewed annually in conjunction with the joint health and safety committee (Section 42).  Documentation and records of training should be maintained as part of the health and safety program.  
 

3.0 HANDLING FLAMMABLE AND COMBUSTIBLE LIQUIDS

3.1  Science Instructor  

The teacher is responsible for participating in the training developed by the School Board for the safe handling of flammable and combustible liquids, and for reviewing procedures for demonstrations in advance of the class.  

The instructor must be present in the classroom at all times during the demonstration, and must be familiar with the classroom and school emergency equipment and systems.   

3.2  Procedures  

  1. Refer to the MSDS for any flammable or combustible liquid before use.  MSDS information should be obtained directly from the supplier of the flammable or combustible liquid, however if necessary MSDS information can be accessed online.  
     
  2. Ensure that areas where experiments are conducted are to be kept clear of combustible materials and obstructions.  
     
  3. When conducting demonstrations, students should be kept a minimum distance of 1 m away from the demonstration area.
     
  4. Handle all flammable and combustible liquids using the appropriate personal protective equipment as described in the MSDS for the liquid being used.
      
  5. Decant/transfer all flammable and combustible liquids into smaller re-sealable containers under the fume hood in the classroom or in the chemical mixing room, where available so that excess vapours will not be emitted near the work area.  
     
  6. Transfer only small amounts of flammable and combustible liquids that are required for the activity being performed.  Transfer using a pipette.
     
  7. Before using any flammable or combustible liquids be sure that all sources of ignition such as open flames, hot surfaces, radiant heat, spontaneous ignition, frictional heat or sparks, static electricity, electrical sparks, stray currents, ovens, furnaces, and heating equipment (bunsen burners, candles, hotplates or spark generating appliances) are eliminated.  

• Be sure that no one (students) has any uncontrolled ignition sources such as matches or lighters, etc. that may inadvertently be used to ignite the liquid.  

• Allow sufficient cooling time (back to room temperature) of any lab equipment before attempting to re-engage the use of any flammable and combustible liquids.

 

4.0 DEMONSTRATION OF INCOMPLETE AND COMPLETE COMBUSTION REACTIONS

4.1  Background Information:  

Incomplete combustion involves the burning of a hydrocarbon with sufficient oxygen to produce CO2 (g) and H2O (v) as well as some solid carbon (soot) and possibly some CO (g).  The result of this is a visible flame.  An example of this is burning a candle:  

C20H42(l) + 23O2(g) → 5C(s) + 5CO(g) + 10CO2(g) + 21H2O(v) (paraffin wax)  

Complete combustion involves the burning of a hydrocarbon with sufficient oxygen to produce only CO2 (g) and H2O (v).  The result of this is an invisible flame.  An example of this is burning a flammable or combustible liquid, such as methanol:  

CH3OH (v) + O2 (g) → CO2 (g) + 2H2O (v)  

When conducting this demonstration, the instructor should give consideration to the hazard of the flammable or combustible liquid.  While methanol is used as an example in this guideline, other liquids such as ethanol or isopropanol are less hazardous.  Ensure that the MSDS has been reviewed in advance of the experiment and that appropriate demonstration equipment and personal protective gear are utilized.  

4.2  General Demonstration Description  

Light a candle and ignite a flammable or combustible liquid (in a pyrex watch glass) to demonstrate the differences between incomplete and complete combustion.  

4.3  Demonstration Details  

Materials:

  • Candle (in a secure base)
  • Approximately 5 mL of flammable or combustible liquid (previously decanted from stock bottle into a small re-sealable container)
  • Watch glass (dish) – two (2)
  • Long stem wooden matches
  • Container of water
  • Safety shield
  • Personal protective equipment
  • pipette  

Safety Considerations:

Refer to the MSDS for flammable or combustible liquid before doing this experiment.  MSDS information should be obtained directly from the supplier of the flammable or combustible liquid, however if necessary MSDS information can be accessed online  

  1. Flammable or combustible liquids should only be transferred in small quantities, and with all sources of ignition extinguished prior to transfer.
     
  2. Use of a safety shield, flame retardant lab wear, appropriate gloves and eye protection are recommended, as are sop up mats.
     
  3. Be sure that students understand that all personal sources of ignition such as matches or personal cigarette lighters be secured and kept away.  

Note:  It is recommended that all safety procedures that are being undertaken be described to the students as part of the demonstration.

4.4  Demonstration Procedures  

4.4.1. General Safety Requirements

  1. Appropriate PPE (personal protective equipment) should be worn by the teacher when conducting demonstrations involving flammable and combustible liquids.  
     
  2. Before putting equipment away or repeating the demonstrations, be sure that all demonstration materials including the watch glass and lab table have cooled back to room temperature.  
     
  3. Dispose of any excess flammable or combustible liquid in a manner consistent with the MSDS.  

4.4.2. Incomplete Combustion  

  1. Make sure that all sources of ignition such as open flames and hot surfaces are extinguished prior to initiating demonstration.  
     
  2. Place a candle in a secure holder and place on laboratory demonstration table.
     
  3. Strike a long stem wooden match and ignite candle.  Extinguish the match by submerging it in water and place on lab table to cool.  
     
  4. Observe and discuss the characteristics of the candle flame.
     
  5. Extinguish the candle flame, and move candle to the side.  Wait for the wick to cool.  

4.4.3. Complete Combustion  

  1. Make sure that all sources of ignition such as open flames and hot surfaces are extinguished prior to initiating demonstration.  
     
  2. Set up the safety shield in front of a small pyrex watch glass.
     
  3. Transfer with a pipette approximately 2-3 mL of flammable or combustible liquid from the supply bottle to the pyrex watch glass. 
     
  4. Reseal the supply bottle and set aside from the laboratory table a distance of at least 2 m.  
     
  5. Strike a long stem wooden match and carefully ignite the liquid by bringing the match to the pyrex watch glass containing the liquid.  Extinguish the match by submerging it in water and place on lab table to cool.  
     
  6. Observe and discuss the characteristics of the flame through the safety shield.
     
  7. Wait until the entire flame has self-extinguished.  Place a second watch glass over the first watch glass.  Remember that flames may be difficult to see.  

4.5  Demonstration Results  

The following experiment shows the results of burning a candle to demonstrate incomplete combustion, and burning methanol to demonstrate complete combustion.  Note that other, less hazardous chemicals such as ethanol or isopropanol will have similar results.

Incomplete Combustion

Complete Combustion

Incomplete combustion involves the burning of a hydrocarbon with insufficient oxygen to produce CO2 (g) and H2O (v) as well as some solid carbon (soot) and possibly some CO (g).  
 
C20H42(l) + 23O2(g) → 5C(s) + 5CO(g) + 10CO2(g) + 21H2O(v)
(paraffin wax)
(*one possible reaction equation)

Complete combustion involves the burning of a hydrocarbon with sufficient oxygen to produce only CO2 (g) and H2O (v)  
 
CH3OH (v) + O2 (g) → CO2 (g) + 2H2O (v)


 Photo of incomplete combustion. source: http://en.wikipedia.org/wiki/Candle
Figure 1: 
http://en.wikipedia.org/wiki/Candle


 Photo of complete combustion. source: http://image02.webshots.com/2/0/53/63/44905363DwmUxl_ph.jpg
Figure 2 : 
http://image02.webshots.com/2/0/53/63/
44905363DwmUxl_ph.jpg

This flame is the yellow-orange flame that is characteristic of a candle flame as a result of the combustion by-products of carbon and carbon monoxide that are produced in addition to the usual combustion products of carbon dioxide and water.

This flame is the blue flame that is characteristic of methanol burning.  It is blue to almost invisible because of the lack of combustion by-products such as carbon and carbon monoxide.

 

5.0 REFERENCES

5.0  The Ontario Fire Code
5.1  Occupational Health and Safety Act
5.2  The Ontario Curriculum – Grades 11 and 12 – Science. Revised 2008