Review form) As well as reaction There is a high heat of solution Possible unexpected heating of glycol–no Standard PPE+ lab 3 3 MD between NaOH solid and EG concern safety goggles Gradually add 80% solution of hydrazine hydrate (65 mL) Less PPE The chemist is exposed to these Extremely hazardous and highly toxic Standard PPE + lab 5 3 S Require use of full face reagents LD50 (rat) 60 mg/kg; IDLH 50 ppm (data safety goggles respirator when from Chemical Hazard Review form) handling N2H4 More reaction The addition rate of 80% Higher reaction rate than expected; None at present 3 2 MR Consider using small hydrazine is too high possible to exceed heat removal capacity scale reaction to determine impact of higher concentration or addition rate of N2H4 Consider adding flow restrictor in N2H4 line Other than flow Control of the hydrazine flow is Higher reaction rate than expected; None at present 4 2 MD lost possible runaway reaction if all N2H4 is added at once Heat the reaction mixture slowly heated to 200 8C over about 3–4 h allowing water to collect in the Dean–Stark trap Reverse flow Water from the Dean Stark trap Flash evaporation of water if reaction T > Chemist monitors 4 2 MD Ensure capacity of back-flows into the reactor 125 8C; possible loss of containment; reaction regularly trap matches expected possible fire volume of water Note: Risk rank categories are S–severe; MJ–major; MD–moderate; MR–minor; ML–minimal (Source: Leggett17). This file is excerpted from “Identifying and Evaluating Hazards in Research Laboratories: Guidelines developed by the Hazard Identification and Evaluation Task Force of the American Chemical Society’s Committee on Chemical Safety”. © Copyright 2015 American Chemical Society
Review form) As well as reaction There is a high heat of solution between NaOH solid and EG Possible unexpected heating of glycol–no concern Standard PPE+ lab safety goggles 3 3 MD Gradually add 80% solution of hydrazine hydrate (65 mL) Less PPE The chemist is exposed to these reagents Extremely hazardous and highly toxic LD50 (rat) 60 mg/kg; IDLH 50 ppm (data from Chemical Hazard Review form) Standard PPE + lab safety goggles 5 3 S Require use of full face respirator when handling N2H4 More reaction The addition rate of 80% hydrazine is too high Higher reaction rate than expected; possible to exceed heat removal capacity None at present 3 2 MR Consider using small scale reaction to determine impact of higher concentration or addition rate of N2H4 Consider adding flow restrictor in N2H4 line Other than flow Control of the hydrazine flow is lost Higher reaction rate than expected; possible runaway reaction if all N2H4 is added at once None at present 4 2 MD Heat the reaction mixture slowly heated to 200 8C over about 3–4 h allowing water to collect in the Dean–Stark trap Reverse flow Water from the Dean Stark trap back-flows into the reactor Flash evaporation of water if reaction T > 125 8C; possible loss of containment; possible fire Chemist monitors reaction regularly 4 2 MD Ensure capacity of trap matches expected volume of water Note: Risk rank categories are S–severe; MJ–major; MD–moderate; MR–minor; ML–minimal (Source: Leggett17). This file is excerpted from “Identifying and Evaluating Hazards in Research Laboratories: Guidelines developed by the Hazard Identification and Evaluation Task Force of the American Chemical Society’s Committee on Chemical Safety”. © Copyright 2015 American Chemical Society