EPA Method 207
Isocyanates in Stationary Source Emissions
Method Overview
- • Isocyanates
- • Isokinetic- M5-type train
- • Reagent - 1,2 PP
- • Analysis by HPLC-UV
- • QA - Blanks Required
Target Compounds
- • 2,4- toluene diisocyante (TDI) in flexible foam production
- • 1,6-amethylene diisocyante (HDI) for paint spray booths
- • methylene diphenyl diisocyanate (MDI) for pressed board
facilitiesmethyl isocyanate (MI)
Method Summary
- • Isocyanates are extracted isokinetically with a modified
method 5 type train
- • Heated probe (glass or quartz), three impingers (with 300,
200, 200 ml of reagent respectively), an empty impinger, a charcoal
impinger, and a silica gel impinger.
- • Water jacketed condenser between 1st and 2nd impinger minimizes
evaporation of toluene
- • Reagent is 1-(2-Pyridyl)piperazine in toluene -"1,2-PP"
- • Sample is evaporated to dryness in the lab and solvent
exchanged to acetonitrile for analysis. This process concentrates
sample to ~70:1 and provides low per train detection limits
- • Analysis is by High Performance Liquid Chromatography (HPLC)
with ultraviolet detection (UV)
- • NOTE - Keep sample cold at all times
Quality Assurance
- • Reagent blank of desorption solvent.
- • Field blank.
- • Recovery Efficiency runs (typically 3 per source / location).
- • Lab Control Spikes - LCS - (typically 2 per set of spiked
tubes).
Shipping Tips
- • Ship as Hazardous Material (call us for IATA codes).
- • Keep 1,2-PP cold at all times after sampling.
- • Order 1,2-PP reagent 4 business days in advance.
- • Don't forget to include shipping costs in your quote.
- • Include a completed Chain of Custody Form in each cooler.
Enthalpy Experience
Our owners contributed to the preliminary method development. Enthalpy
field tested the method and evaluated different reagents while under
contract to a major isocyanate manufacturer. Ruggedness and interlaboratory
comparison tests proved the method's reliability.
