AATCC 134-2016 Electrostatic Propensity of Carpets.
9.1 Test TM134 Static Unprotected Control Carpet without an underlay (to avoid charging the underlay) and the Static Protected Control Carpet with an underlay at the beginning of each testing session. If the results are outside of the test laboratory’s Control Chart Control Limits, then seek the cause of the devia- tion and correct the problem. Check relative humidity and temperature (current values and recorded values during the specimen conditioning period) (see 6.1). Test backup Control Carpets if available (see 6.6), reclean soles (see 9.7) and check instrument calibration. Use a blow- ing-fan, handheld, balanced highvoltage ionizer to neutralize any charge on the underlay pad between tests and prior to testing any specimen, moving it slowly over the entire surface at a height of about 100-200 mm above it for at least 1 min.
9.2 Test the specimen once a day until two reproducible voltages are obtained. Voltages are considered reproducible when consecutive tests agree within 10% or 0.5 kV, whichever is greater. Leaving the specimen in the test chamber over- night should allow any static charges to be dissipated. This process may be accelerated by using a blowing-fan, balanced highvoltage ionizer to neutralize any charges. If an ionizer is used to thor- oughly neutralize the specimen (held about 100-200 mm above the specimen and moved slowly over its entire surface, requiring approximately 1-2 min), the same specimen may be retested the same day.
9.3 Test the specimen over the standard underlay (see 6.5), which is placed on the grounded metal plate.
9.3.1 Residual static charges on the specimen and underlay have been found to be a major source of error. Residual charges should decay naturally over a period of several hours. Specimens should be hung undisturbed for a minimum of 4 h, or thoroughly neutralized with a blow- ing-fan, balanced highvoltage ionizer, prior to each testing, as above.
9.3.2 Lay the underlay on the grounded metal plate, rubberized side up. Avoid dragging the underlay across the surface or rubbing different parts of it together.
9.3.3 If a blowing-fan, balanced high- voltage ionizer is available, thoroughly and slowly cover the entire surface of the underlay with the ionizer output, holding the ionizer about 100-200 mm above the underlay. This will neutralize any resid- ual charges from handling.
9.3.4 Lay the specimen on the underlay carefully to avoid excessive friction against the mat or rubbing different parts of it together.
9.3.5 If a blowing-fan, balanced high- voltage ionizer is available, thoroughly and slowly cover the entire surface of the sample with the ionizer output, holding the ionizer about 100-200 mm above the sample. This will neutralize any residual charges from handling. 9.3.6 Zero the test apparatus. Place clean test sandals (see 9.7) on the speci- men, grasp the test probe and ground the test operator while standing off the speci- men in stocking feet. Ensure that the re- corder reads “0.” Step into the clean test sandals specified for the test while stand- ing on the specimen and holding the test probe, being careful not to move the san- dals around on the specimen.
9.4 After following the procedure in 9.3, there should be very little voltage indication. Presence of significant voltage (more than 200 V) indicates excessive initial charge somewhere in the system and the procedures in 9.2 and 9.3 must be repeated to avoid possible significant errors. Since the location of the spurious charge is important in affecting the final test results, it is not sufficient to simply reground the test subject, although this will obviously create a new zero value.AATCC 134 pdf download.