Using a hotplate with flammable liquid Table 10-3 Department: Description of Operation: By: Chemistry Use of stirring hotplate with flammable liquid Review Team Date: What if? Answer Probability Consequences Recommendations Use on Flammable vapors could High Extensive Use in fume hood unventilated accumulate and reach damage/downtime benchtop source of ignition fire and costs Overexposure to toxic High Adverse health Use in fume hood vapors effects Mechanical Lack of exhaust but Moderate Adverse health Interlock hotplate power to failure of fume vapors still accumulate effects exhaust monitor hood exhaust and ignition sources still fan present Fire Moderate Damage Use explosion proof hotplate Power failure Lack of exhaust, vapors Very high Damage/health Connect exhaust fan to during use (see may accumulate but at effects emergency power also loss of heat lesser magnitude, and loss of potential fire stirring below) Reaction becomes Very high Failed experiment, Conduct a review of all unstable exposure to possible reactions and unknown products outcomes Possible fire in hotplate Moderate Equipment Check electrical connections and ignition of solvent damage/personnel (plugs and wires); pretest Hotplate vapors injuries hotplate before starting; use malfunction, explosion proof hotplate electrical arcing (switch/ thermostat) Hotplate Heat material above Moderate Fire, damage, Interlock hotplate to malfunction, flash point personnel injuries temperature feedback loop supplies too Reaction becomes Moderate Personnel injuries Do not leave reaction much heat unstable unattended; check temperature of reaction at regular intervals Unintended reaction Moderate Hazardous Conduct a review of all occurs byproducts possible reactions and outcomes Hotplate Reaction unsuccessful Moderate Lost time and Interlock hotplate to malfunction; materials temperature feedback loop supplies too Reactants degrade/ Moderate Lost time and Do not leave reaction little heat; if no evaporate materials; unattended; check heat, see loss of hazardous temperature of reaction at power above byproducts regular intervals Loss of Stirring Superheating of portion Very high Vessel fails/fire Interlock hotplate to of flask contents temperature feedback loop Unintended reaction High Hazardous Conduct a review of all occurs byproducts possible reactions and outcomes Reaction unsuccessful High Lost time and Do not leave reaction materials unattended; check temperature and stirring of reaction at regular intervals
Using a hotplate with flammable liquid Table 10-3 Department: Chemistry Description of Operation: Use of stirring hotplate with flammable liquid By: Review Team Date: What if? Answer Probability Consequences Recommendations Use on unventilated benchtop Flammable vapors could accumulate and reach source of ignition fire High Extensive damage/downtime and costs Use in fume hood Overexposure to toxic vapors High Adverse health effects Use in fume hood Mechanical failure of fume hood exhaust fan Lack of exhaust but vapors still accumulate and ignition sources still present Moderate Adverse health effects Interlock hotplate power to exhaust monitor Fire Moderate Damage Use explosion proof hotplate Power failure during use (see also loss of heat and loss of stirring below) Lack of exhaust, vapors may accumulate but at lesser magnitude, potential fire Very high Damage/health effects Connect exhaust fan to emergency power Reaction becomes unstable Very high Failed experiment, exposure to unknown products Conduct a review of all possible reactions and outcomes Hotplate malfunction, electrical arcing (switch/ thermostat) Possible fire in hotplate and ignition of solvent vapors Moderate Equipment damage/personnel injuries Check electrical connections (plugs and wires); pretest hotplate before starting; use explosion proof hotplate Hotplate malfunction, supplies too much heat Heat material above flash point Moderate Fire, damage, personnel injuries Interlock hotplate to temperature feedback loop Reaction becomes unstable Moderate Personnel injuries Do not leave reaction unattended; check temperature of reaction at regular intervals Unintended reaction occurs Moderate Hazardous byproducts Conduct a review of all possible reactions and outcomes Hotplate malfunction; supplies too little heat; if no heat, see loss of power above Reaction unsuccessful Moderate Lost time and materials Interlock hotplate to temperature feedback loop Reactants degrade/ evaporate Moderate Lost time and materials; hazardous byproducts Do not leave reaction unattended; check temperature of reaction at regular intervals Loss of Stirring Superheating of portion of flask contents Very high Vessel fails/fire Interlock hotplate to temperature feedback loop Unintended reaction occurs High Hazardous byproducts Conduct a review of all possible reactions and outcomes Reaction unsuccessful High Lost time and materials Do not leave reaction unattended; check temperature and stirring of reaction at regular intervals
table-10-3-using-a-hotplate-with-flammable-liquid-example.docx