BS EN 16778-2016 pdf download.Protective gloves The determination of Dimethylformamide in gloves.
This BS EN 16778 specifies a test method for the determination of Dimethylformamide (DMFa — CAS N° 68 12.2) in glove materials.
NOTE For Dimethylformamide the following abbreviations can be used: DMF, DMFa DMFo.
The test method is applicable for the following materials:
— polyurethane (PU) materials (except elastane). PU Coated material (textile, leather), PU foam, PU blended materials;
— adhesives;
— all materials manufactured with a dipping process using DMFa.
2 Normative references
Not applicable.
3 Principle
The sample is cut into small pieces and extracted with methanol in a sealed flask in an ultrasonic bath. An aliquot of the extract is analysed with GC-MS.
4 Consumables
4.1 Reagents
The substances are given in Table 1.
4.2 Stock solutions
4.2.1 Internal standard — Stock solution (1000 mg/I)
100mg of [)MFa-d7 is weighed with an accuracy oIO,1 mg in a 100 ml volumetric flask and filled with methanol to the mark and stored at 4 °C, for maximum I month.
4.2.2 Internal standard — working solution (200 mg/I)
The solution is prepared by 1:5 dilution of the stock solution (4.2.1) with methanol. Storage conditions maximum of 1 month at 4°C.
4.2.3 Target compound — Stock solution (1000 mg/I)
100 mg of DMFa is weighed with an accuracy of 0.1 mg in a 100 ml volumetric flask and filled up to the mark with methanol and stored at 4 °C for maximum I month.
4.2.4 Target compound — working solution (200 mg/I)
The solution is prepared by 1:5 dilution of the stock solution (4.2.3) with methanol. Storage conditions maximum of I month at 4°C.
4.2.5 Extraction solution containing 20 mg/I Internal standard
Add 100 ml internal standard — working solution (4.2.2) in a 1000 ml volumetric flask and fill it with Methanol to the 1000 ml calibration mark. This solution can be stored in a vessel at 4°C for 6 months.
5. Equipment
Usual lab equipment, in addition:
5.1 analytIcal balance (precision at least 0,1 mg);
5.2 sealed flask (for instance, Erlenmeyer) with screw cap and polytetrafluoroethylene (PTFE) seal.
250 ml;
5.3 ultrasonic bath capable of maintaining a temperature of (70 ± 5) °C;
5.4 PTFE-membrane filter pore width 0.45 pm;
5.5 suitable sample vials with PTFE-capped for GC-MS analysis;
5.6 volumetrIc flask, 10 ml, 100 ml, 1000 ml;
5.7 range of micropipettes and dispenser with volume between 20 p1 to 200 ml;
5.8 gas chromatograph with mass detector.
6 Test procedure
6.1 Sampling
The sample shall consist of a least a pair of gloves.
6.2 Conditioning
When the gloves are received, the laboratory shall package them into an airtight plastic sealed bag (e.g. polyethylene bag) before the start of the preparation steps. Vacuum sealer shall not be used.
If stored for more than 24 h before testing, the gloves shall be kept at (4 ± 3) °C.
NOTE During the validation Interlaboratory test, It has been demonstrated that alS day’s storage In sealed plastic bag at 4 °C has shown no significant difference in results.
The sample (in the seal plastic bag) shall be conditioned (24 ± 1) hours at (23 ± 2) °C prior to the preparation.
6.4 Extraction
The extraction shall be started maximum (30 ± 5) minutes after the weighing of the tests pieces.
Each test piece is put in a 250 ml Erlenmeyer flask. (5.2). Add the stored extraction solution (4.2.5) at a ratio of 10.0 ml per 1.0 g cut up test piece. The closure is to maintain safe and gas tight, throughout the complete extraction.
The sample is then extracted 30 mm at a temperature of 70 °C in an Ultrasonic bath.
WARNING — Extraction at 70°C leads to overpressure and the risk of uncontrolled emission of Methanol and loss of DMFa.
After cooling to room temperature, the solution is filtered through a PTFE membrane filter (5.4). An aliquot of the extract is transferred to a GC-MS vial and sealed with a PTFE-cap (5.5).
The sealing should be done by well-trained operator to avoid any leakage.
6.5 Determination with GC-MS
6.5.1 CalibratIon
Five calibrations points are used to establish the calibration curve, they are all prepared in 10 ml volumetric flasks, as stated in Table 2. A 6th point. L.o. a blank, shall be included in the calibration curve.BS EN 16778-2016 pdf download.