Analysis of formic acid in air samples.

Details

• Personal Author:
  Smallwood, Anthony W.
• Description:
  A method for the determination of airborne formic-acid (64186) was described. Air samples were drawn through a midget impinger containing 15 milliliters of 0.1 normal sodium-hydroxide (1310732) at a sampling rate of 1 liter per minute for 42 minutes. Derivatizing solution, containing a mixture of ethanol (64175) and sulfuric-acid (7664939), was then added to an aliquot taken from the impinger, and sealed in a gastight reaction vial. After 2 hours, the ethyl-formate (109944) vapor which was formed in the headspace in the vial was analyzed by gas chromatography. The quantity of ethyl-formate was proportional to the quantity of formic-acid in the vial. The advantages and disadvantages of headspace analysis were discussed. Although the percent recovery of this procedure was not investigated since it involved the reaction of a strong base with a moderately strong acid, the reaction was assumed to go to completion. The author concludes that the method was precise for the determination of formic-acid in air at 0.1 of threshold limit value of 9mg/m3, with a relative standard deviation of 11 percent. [Description provided by NIOSH]
• Subjects:
  Chemistry Chemistry, Analytic Chromatography Occupational Health Safety
• Keywords:
  Acid-base-equilibrium Alcohols Analytical-chemistry Analytical-methods Carboxylic-acids Chromatographic-analysis Formates Gas-chromatography NIOSH-Author Threshold-limit-values
• ISSN:
  0002-8894
• Document Type:
  Text
• Genre:
  Journal Article
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  151-153
• Volume:
  39
• Issue:
  2
• NIOSHTIC Number:
  nn:00167405
• Citation:
  Am Ind Hyg Assoc J 1978 Feb; 39(2):151-153
• CAS Registry Number:
  Ethanol (CAS RN 64-17-5) ; Ethyl formate (CAS RN 109-94-4) ; Formic acid (CAS RN 64-18-6) ; Sodium hydroxide (CAS RN 1310-73-2) ; Sulfuric acid (CAS RN 7664-93-9)
• Federal Fiscal Year:
  1978
• Peer Reviewed:
  True
• Source Full Name:
  American Industrial Hygiene Association Journal
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:216be6e3e94ee1cf8508028d400e7b3a0f2a6f02b17c8eb29d94f17ffc2f193af4236cbf7f2fa195a66889d352202cb38635b3306cd9dabe774161216846d005
• Download URL:
  https://stacks.cdc.gov/view/cdc/185133/cdc_185133_DS1.pdf
• File Type:
  [PDF - 304.74 KB ]