Page:NIOSH Manual of Analytical Methods - 5524.pdf/1

 METALWORKING FLUIDS (MWF) ALL CATEGORIES DEFINITION:  Metalworking fluids 		  CAS:  None METHOD: 5524, Issue 2

EVALUATION: FULL

5524

RTECS: None Issue 2: 29 December 2014 Issue 1: 15 March 2003

PROPERTIES: Not defined. Fluids may contain varying amounts of mineral oil, emulsifiers, water, alkanolamines, polyethoxyethanols, biocides, surfactants, pressure additives and boron compounds.

OSHA :	 No PEL NIOSH:	0.4 mg/m3  as thoracic fraction (0.5 mg/m3  as ‘total’ aerosol) Other OELs:	 [1,2]*

SYNONYMS: Metalworking fluids (MWF), metal removal fluids, machining fluids, mineral oils, straight fluids, soluble fluids, synthetic fluids and semi-synthetic fluids SAMPLING

MEASUREMENT

SAMPLER:	 Thoracic particles: FILTER + CYCLONE (tared 37-mm, 2-µm polytetrafluoroethylene (PTFE) filter + thoracic cyclone) Total particulate: tared 37-mm, 2-µm PTFE filter FLOW RATE:	 Thoracic – 1.6 L/min, Total – 2 L/min VOL-MIN: MAX:

768 L at 0.4 mg/m or 0.5 mg/m Not determined 3

TECHNIQUE:

Gravimetric

ANALYTE:

Airborne metalworking fluid aerosol

EXTRACTION:

Ternary solvent: dichloromethane: methanol:toluene (1:1:1) Binary solvent: methanol: water (1:1)

BALANCE:

0.001 mg sensitivity; use same balance before and after sample collection

CALIBRATION:

National Institute of Standards and Technology Class S-1.1 weights or ASTM Class 1 weights

RANGE:

0.05 to 2 mg per sample

3

SHIPMENT:	 Ship overnight in a refrigerated container SAMPLE STABILITY:	 Refrigerate upon receipt; analyze within 2 weeks of collection BLANKS: BULK SAMPLE:

At least 5 field blanks per set

ESTIMATED LOD:	 Total weight - 0.03 mg per sample [3] Extracted weight - 0.03 mg per sample weight [3]

One for each fluid at each site for solubility testing

PRECISION (  S r ):	 Total weight - 0.04 (≥ 0.2 mg/sample) [4] Extracted weight - 0.05 (≥ 0.2 mg/ sample) [4]

ACCURACY RANGE STUDIED:

0.05 to 0.9 mg/sample

BIAS:

Not determined

OVERALL PRECISION (ŜrT): ACCURACY (Estimated):

Total weight- 0.06 Extracted weight - 0.07 Total weight - 0.12 Extracted weight - 0.14

APPLICABILITY: The method is applicable to all metalworking fluids-straight, soluble, synthetic and semi-synthetic as long as they are soluble in the extraction solvent regimen [4,5]. Only one MWF (Glacier, Solutia Inc.) has thus far been found to be insoluble in the ternary extraction solvent; however, that MWF is soluble in the binary blend and tests have shown that the binary solvent in combination with the ternary solvent is effective in extracting this fluid [6]. Thoracic samplers meeting the International Standard ISO 7708 thoracic convention within the performance specifications of the European Standard EN13205, parts 1 through 6 [2] may be considered for this method if they have been validated for the collection of MWF. Depending on the type of thoracic sampler used, the recommended flow rate may differ from that specified above. Sampling at flow rates exceeding those recommended here may result in increased evaporative loss of sample. Welding fume may significantly interfere with proper operation of certain impactor-style samplers. NIOSH Manual of Analytical Methods (NMAM), Fifth Edition