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AS ISO/IEC 17025-2005

WORK INSTRUCTIONS QC TESTING (etc) 4-August-2009 pg 1

WORK INSTRUCTIONS

QC TEST METHODS

WITH

NATA EQUIPMENT CALIBRATION

AND USER CHECKS

This revision August 2009.

New or altered text since previous revision denoted

by red text.

Previous revision 5th June 2007.

Revision Date: December 2004

AS ISO/IEC 17025-2005


TABLE OF CONTENTS

SAMPLING PROCEDURE 3

CONDITIONS OF TEST 4

BALANCES – SINGLE POINT AND ZERO CHECKS

SINGLE POINT CHECK 5

FLOW CUP CALIBRATION 3

TIMER ACCURACY CHECK 10

GRIND GAUGE CHECK 10

pH METER JUNCTION POTENTIAL CHECK 10

PYCNOMETER CALIBRATION 6

THERMOMETERS – SINGLE POINT CHECK and ICE POINT 4

VISCOMETER - KREBS STORMER CHECK 3

SPATULA (SETTLING) CHECK 5

AS ISO/IEC 17025-2005


SAMPLING PROCEDURE

1. Introduction

This work instruction sets out the procedure by which a production batch is sampled, for both "in process" and "final QC" testing, as well as "retain” samples.

2. Apparatus

a) 500ml 'open head' tinplate cans are used for “final QC” and “retain” samples b) for in-process checks, 150ml plastic cups are usually deemed sufficient

3. Procedure

a) When sampling, ensure all apparatus used is clean and dry, and that the sample is not at risk of being contaminated by any other material than that being sampled.

b) The 500ml tinplate cans should be filled to nominally 500ml for "final QC" and “retain” sampling. For other "in-process" checks, 150ml plastic cups are usually adequate (as the discretion of the Technical Manager or their nominee).

c) When sampling, care shall be taken that the material is uniformly mixed and remains so during the sampling operation. Samples drawn during filling may be taken from the filling point, or from already filled containers.

d) Should sampling post-filling be required, then wherever practical, an original unopened container selected at random shall be taken as the sample. If this is not practical, consult reference AS 1580.102.1-2002 clauses 7.4.2, 7.4.3 and 7.4.4 (as applicable).

e) Samples for QC testing should be

(i) identified as to provide unambiguous recognition of the sample under test

Samples taken for retain purposes shall be identified by a label comprising

(i) product code of material

(ii) batch number

(iii) date of manufacture

(iv) optionally, the product name.

4. Reference

AS 1580.102.1 -2002

AS ISO/IEC 17025-2005


CONDITIONS OF TEST

1. Introduction

This work instruction sets out the requirements for the conditioning and testing of paints and painted panels (as applicable), wherein the ambient temperature is controlled.

2. Apparatus

a) thermometer approved for use by these work instructions, covering the applicable temperature range, capable of resolving 1.0°C (minimum).

3. Procedure

a) The thermometer shall be brought into thermal equilibrium with the testing environment before use and shall be so maintained throughout the test period; a conditioning period of at least 4 hours is recommended.

b) The testing should be carried out in accordance with the following test conditions

"Referee" testing, as used in cases of dispute 25 +/-1.0°C

"Routine" testing, as used for all other testing 23 +/-3.0°C

c) The temperature shall be recorded at

(i) the commencement of the test

(ii) every ten minutes throughout the test

(iii) at the conclusion of the test, except when the test is completed within10 minutes, in which case the commencement temperature shall be deemed a sufficient record.

4. Reference

AS 1580.101.4 -1999.

AS ISO/IEC 17025-2005


THERMOMETERS – SINGLE POINT CHECK and ICE POINT

1. Introduction

This work instruction sets out the method by which to check the accuracy of working thermometers as used for QC testing, both upon purchase and as they age, by means of a periodic comparison with a NATA certified reference thermometer.

2. Apparatus

a) For ice point check; distilled liquid water containing distilled water ice cubes at equilibrium temperature in a polystyrene foam cup sitting inside a second polystyrene foam cup.

b) NATA certified reference thermometer.

c) Working thermometers to be tested (uniquely identified).

3. Procedure

Upon the introduction of a new thermometer for use:

a) Check the new thermometer against the reference thermometer at the ice point, as well as several points over the working range.

b) At routine room temperature (23 +/-3.0°C), compare working thermometer temperature reading against certified thermometer reading.

c) Note variances on labels and attach to thermometers.

Every six months:

a) At routine room temperature (23 +/-3.0°C), compare working thermometer temperature reading against certified thermometer reading.

b) Note variances on labels and attach to thermometers.

c) Check the reference thermometer at the ice point. Record the variances over the life of thermometer to detect any anomalies.

4. Report

a) Fill out the calibration book noting date, operator’s name and reference to this method.

b) All workings / calculations to be shown.

c) Acceptance Criteria.

± 2% of the maximum range, i.e. ±1.0°C for 50°C, ±2.0°C for 110°C, ±8°C for 400°C.

If variance falls within acceptance criteria, sign “Suitable for Use”. If variance falls outside criteria, consult Technical Manager and retest. If the variance is still outside criteria, remove thermometer from service.

d) Note variances on label, with unique identifier, and attach to corresponding thermometer.

5. Reference

NATA Technical Note 19, Liquid-in-Glass Thermometers (June 2009)

Supplementary Requirements for accreditation in the field of Chemical Testing (Jan 2007)

AS ISO/IEC 17025-2005


BALANCES – SINGLE POINT AND ZERO CHECKS

1. Introduction

Every three years (maximum), the laboratory scales are externally calibrated by a NATA accredited laboratory. NATA requires that every six months, a repeatability check is performed; this is currently being performed by the same NATA accredited laboratory.

NATA further requires that a ‘single point check’ be performed every month, with a suitable mass of not less than 80% of the full capacity of the balance range being checked. If the mass is less than 80%, the scale must be clearly identified as “not for NATA use above X grams”, where X is the mass being used.

These checks are being performed with a ‘user assigned mass’.

NATA also requires that a zero point check be performed before each weighing.

2. Apparatus

a) Balances

b) User assigned masses (immediately after a full three year calibration, these masses are placed on each balance and assigned a value specific to that balance).

3. Procedure a) For each balance and its user assigned masses, record following set of observations:

Tare; 1st Zero Reading; 1st Reading; remove and replace; 2nd Reading; 2nd Zero Reading.

b) Use these figures to calculate the correction, and to determine the change in correction.

4. Calculations

Certified calibrating mass (M) = 1st zero reading (Z1) = 1st reading of standard mass (M1) = 2nd reading of standard mass (M2) = 2nd zero reading (Z2) =

C1= M – (M1-Z1) = C2= M – (M2-Z2) = Correction = (C1+C2) / 2 =

If the change in correction is less than 3 times the maximum standard deviation of the repeatability readings (refer 3 year calibration report), the balance is fit for continued use.

5. Reporting

a) Fill out the calibration book noting date, operator’s name and reference to this method.

b) Acceptance criteria detailed above. Report if balance is fit for continued use (or not).

c) If a balance is not fit, consult with the Technical Manager regarding this non conformance.

6. Reference

Nata Technical Note 13, Oct 2007.

AS ISO/IEC 17025-2005


Supplementary Requirements for accreditation in the field of Chemical Testing (Jan 2007)

PYCNOMETER (S.G. CUP) -CALIBRATION

1. Introduction

This procedure describes the determination of the volume of the pycnometer. This is done bycalculating the volume from the nett weight of distilled water from its known density at25°C.

2. Apparatus

a) Clean and dry pycometer b) Analytical balance accurate to four decimal places. c) Thermometer accurate to 25°C +/-0.5°C. d) Distilled water.

3. Procedure

a) Proceed quickly to avoid temperature deviation. b) Bring both distilled water and pycnometer to 25°C +/-0.5°C. c) Weigh the empty pycnometer (cup and lid) and tare analytical balance to zero. d) Pour the distilled water into the cup until it is sufficiently full for the water to exude through the hole in the lid when it is put in place. Avoid entrapment of air. Record temperature of distilled water in cup. e) Place lid on cup, wipe off excess water. f) Weigh the pycnometer and water on the tared balance to four decimal places. Record the weight. g) Remeasure the temperature of the distilled water in the pycnometer and record the temperature. If the temperature falls outside 25°C +/-0.5°C repeat steps b) to f). 4. Calculation

The volume of the pycnometer is calculated by dividing the nett weight of distilled water inthe cup divided by its known density at 25°C.

Volume = (Mass of pycnometer plus contents) – (Mass of empty pycnometer) / (density of water)

{grams / (grams/mL)}

Volume = Nett Weight / 0.997 (density of water at 25°C) Correction Factor = Volume / 100

Then actual density = measured density x correction factor.

5. Reporting

a) Fill out the calibration book noting date of calibration, operators name and reference to this method. b) All workings/calculations to be shown. c) Acceptance Criteria -Correction factor to be used if reading falls within range 1.000 +/-0.005 (ie 0.995 to 1.005) If reading falls inside acceptance range sign “Suitable for Use”. If reading falls outside acceptance range, retest and inform Technical Manager re: Corrective

AS ISO/IEC 17025-2005


Action to be implemented. d) No blocking out or liquid paper to be used. Any mistakes to be neatly crossed out and the correct figure to be written and initialled. e) The calibration factor to be displayed in close proximity to the S G cup. f) Calibration to be conducted at six monthly intervals or immediately if the cup is damaged or deformed.

6. Reference

AS1580.202.1 – 1995 – Density SI Chemical Data – 1981 – Aylward and Findlay – P128

FLOW CUP CALIBRATION

1. Introduction

This procedure sets out the calibration requirements and procedures for flow cups used in thedetermination of consistency. Cups which are in constant use should be calibrated at threemonthly intervals.

2. Apparatus

a) Flow cup.b) Stand and level barc) Thermometerd) Timere) Three standard mineral oils – viscosities of the order 100mm2/S, 200mm2/S and 300mm2/S at 25°C. (if available; at least two oils must be used). 3. Procedure

a) Determine the time of flow of each oil as per AS1580.214-2. b) Carry out three determinations of each oil and calculate the mean efflux time for the cup for each oil.

4. Calculations – Per Oil

a) Actual efflux time – (refer Evic QC work instruction, Reference Document No 4)1) Temperature = 25.0°C ( +/-0.5°C )2) Record 3 readings and calculate mean

b) Theoretical efflux time equation: t = 0.3453V + 2.75, where t = theoretical efflux time, in secondsV = kinematic viscosity of the certified oil, mm2/S

Eg, if the kinematic viscosities of an oils was 195.7 mm2/S, then the theoretical efflux time for the cup would be:

t = (0.3453 x 195.7) + 2.75 = 70s

5. Calibration Graph

Plot the best straight line fit of actual efflux time vs theoretical efflux time.

6. Reporting

a) Fill out calibration book noting date of calibration, operators name and reference method.b) All workings/calculations to be shown.

I. Actual Efflux Times II. Theoretical Efflux times III. Acceptance Criteria – Actual Efflux Time must not vary by more than 15% from Theoretical Efflux Time c) If reading falls within acceptance criteria sign “Suitable for Use”If

reading falls outside criteria retest and then inform Technical Manager re: corrective action to be implementedd) No blocking out or liquid paper to be used. Any mistakes to be neatly crossed out and

AS ISO/IEC 17025-2005


thecorrect figure to be written and initialled.e) Calibration to be conducted at three monthly intervals or immediately if the cup isdamaged or deformed.

7. Reference AS1580.214.2 – 1990 – Calibration of Flow Cup. KREBS – STORMER VISCOMETER CALIBRATION

1. Introduction

The normal period between successive calibration of viscometers is one year. Nata requires: a) Initial check – masses and paddle dimensions (see Dimensions Report Doc 187 – Equipment Calibration – Nata Requirements – Workbook). b) Annual check – against standard certified oils (see Current Certified Reference Oil Test Reports – Viscometer Oils – filed in Doc 187 Equipment Calibration – Nata Requirements – Workbook).

2. Apparatus

a) Krebs – Stormer Viscometer b) Two standard certified oils.c) Thermometer

3. Procedure

a) Obtain two certified oils spanning the anticipated range of viscosity at 25oC and differing in viscosity by at least 0.05 PaS. Note: The viscosity of reference oil may change with time. The oil may only be used before its certification expiry date (two years after its date of certification). b) Determine for each oil the mass, in grams required to produce 200 revolutions of the rotor within 60 seconds. c) Using the determined mass and DYNAMIC viscosity of the oils, plot the points on the graph.

4. Reporting

a) Fill out calibration book noting date of calibration, operators name and reference method.b) All workings/calculations to be shown.c) Acceptance criteria +/-15% of expected load for 200 RPM for a given oil and within +/5% of the consistency in kreb units. If the points fall within the band, the instrument isperforming satisfactorily relative to the ‘standard’ Stormer Viscometer. The boundry lines ofthe band represent + 4gm tolerance from the ‘standard’ broken line. Sign “suitable for use”.If any point falls outside the band, a fresh performance check should be carried out. If anypoint on this repeat still lies outside the band, inform the Quality System Co-Ordiantor regarding corrective action to be implemented.d) No blocking out or liquid paper to be used. Any mistakes to be neatly crossed out and thecorrect figure to be written and initialled.

5. Reference

AS1580.214.1 TIMERS -CALIBRATION

1. Introduction

This procedure sets out method of calibrating time pieces used as apparatus in other testingmethods.

AS ISO/IEC 17025-2005


2. Apparatus

a) Timersb) Telephone

3. Procedure

a) Set timer ready b) Ring Telstra "speaking clock" – Record time. c) Push timer at required time frame given by Telstra. d) After one hour, ring Telstra. e) At this time record Telstra time and timer mechanism time.

4. Calculation

Telstra Time Period = Telstra finish time – Telstra start time compare to Timer Time Period = Timer

finish time – Timer start time

5. Reporting

a) Fill out calibration book noting date of calibration, operators name and reference method. b) All works/calculations to be shown. c) Acceptance Criteria = +/-5 second in 15 minutes If reading falls with and attach timer calibration sticker. in acceptance criteria sign “Suitable for Use” If reading falls outside criteria retest and then inform Quality System Co-Ordinator re: corrective action to be implemented. d) No blocking out or liquid paper to be used. Any mistakes to be neatly crossed out and the correct figure to be written and initialled. e) Calibration to be conducted at three monthly intervals or immediately if the timer is damaged.

6. Reference

Nata General Requirements for RegistrationAppendix 1 – Calibration of Common Testing Equipment PH METER JUNCTION POTENTIAL TEST

1. Introduction

This procedure describes the method to determine the junction potential of pH electrode.

2. Apparatus

a) pH measuring instrument capable of measuring accurately to nearest 0.1 pH unit. b) Clean, maintained pH electrode suited to instrument. c) Standard pH 7 and 10 phosphate buffer solutions.

3. Procedure

a) Measure pH of buffer solution. b) Measure same buffer solution diluted with nine parts of freshly boiled deionised water. c) Compare results. d) Conduct test for each buffer solution.

AS ISO/IEC 17025-2005


4. Results

The pH of the diluted solution should be 0.20 +/-0.05 units higher than the original buffer. i.e. the range should be 0.15 -0.25 If the values obtained are outside the above range, the reference electrode requires alternation – see pH meter manual.

5. Reporting

a) Fill out calibration book – date of performance check, operators name and reference method. b) All workings/calculations to be shown. c) Acceptance criteria to fall within range 0.15 -0.25 units If reading falls within acceptance criteria sign “Suitable for Use” If reading falls outside criteria retest and then inform Quality System Co-Ordinator re: corrective action to be implemented. d) No blocking out or liquid paper to be used. Any mistakes to be neatly crossed out and the correct figure written in and initialled. e) Performance check to be conducted at three monthly intervals or immediately if electrode is damaged.

6. References Nata Technical Note 21 – July 1995 – Reference 4.2.2. VISCOSITY AND YIELD ADJUSTMENT

1. Introduction

This procedure outlines the quality control method used to specify the proportions ofviscosity reducer (usually solvent) and viscosity enhancer (usually resin or thickener modifier) in the final letdown phase of paint production. These proportions are dictated byboth the viscosity specification range and a ±2.0% w/w allowable production yield tolerance.

2. Apparatus

a) Digital weighing balance accurate to two decimal places. b) Pre-specified viscometer -either an B4 cup of a Stormer.

3. Procedure

a) Determine the initial viscosity of prefinished paint freshly sampled from the productionvat. b) Use the figures printed on the Production Sheet to calculate the theoretical remaining weight required to achieve 100.0% weight yield.d) Conserving this theoretical remaining weight for 100.0% weight yield, judge theproportions of ingredients (specified on the Production Sheet) required to achieve a viscositythat falls within the specified viscosity range. Add these amounts to the laboratorysample and check the viscosity. Any other additives such as tinters, defoamers, etc. should be included when determining the viscosity. NOTES: (i) Without prior experience, the technique of judging proportions of ingredients toachieve a certain viscosity is normally developed through trial and error. (ii) If resin is used to increase viscosity, do not exceed 5 w/w% added resin on totalresin already in the formula without first consulting Technical Manager or his/her nominee. e) If a reasonable viscosity is achievable at the 100.0% weight yield mark, then scalethe laboratory

AS ISO/IEC 17025-2005


proportions of ingredients for production and recheck the viscosity of a factorysample after modification. If a reasonable viscosity is unachievable at the 100.0% weightyield mark, then go to step e) otherwise this procedure is complete.f) Repeat step c) using the full 98.0 to 102.0% weight yield latitude as necessary. If areasonable viscosity is achievable between 98.0 and 102.0% weight yield, then scale thelaboratory proportions of ingredients for production and re-check the viscosity of a factorysample after modification. If a reasonable viscosity is unachievable between 98.0 and 102.0%weight yield, then consult Chief Chemist or his/her nominee for further instructions. S.G. (SPECIFIC GRAVITY) OR DENSITY

1. Introduction

This procedure describes the determination of the density (mass per volume) of a liquid paint.The result allows: (i) monitoring of consistency between batches of the paint in question; and (ii) weights to be calculated for filling of packaging cans (normally sold by litreage).

2. Apparatus

a) Clean, dry and undamaged 100 ml pycnometer.b) Digital weighing balance accurate to two decimal places c) Thermometer/s.

3. Procedure

a) Take sample in accordance with "sampling procedure" QC work instruction. Proceed quickly to avoid significant temperature deviation. b) Keeping sample well mixed, bring to 25±1°C. Proceed quickly to avoid significant temperature deviation. c) Weigh the empty pycnometer cup and lid, and tare scales to zero. d) Pour the paint sample into the cup until it is sufficiently full for the paint to exude through the hole in the lid when it is put on. Avoid entrapment of air; skim bubbles using a spatula if necessary. e) Place lid on cup, wipe off excess paint that passes through the hole. f) Weigh the cup and contents on tared scales to 0.01 of a gram. g) Remeasure temperature of test sample; repeat steps b) to g) if temperature falls outside of 25±1°C. h) Calculate S.G. as follows

S.G. = (net weight of paint in pycnometer) / 100 x correction factor1

(1

refer Pycnometer Calibration prodcedure)

If the S.G. falls outside the specified range, consult the Technical Manager; the Tare Weight procedure may be of benefit in determining the should be carried out to check that the more weight significant ingredients have been added.

4. Calculation The S.G. is calculated by the equation given above. Report the S.G. to three significant figures. eg (92.6 g/100 = 0.926; 102g/100 = 1.02)

5. Reference

AS1580 Method 202.1

AS ISO/IEC 17025-2005


FINENESS OF GRIND (general use and annual reference check)

1. Introduction

Two paints

This procedure describes the determination of the fineness of grind of paints and related materials. The fineness of grind obtained on a standard gauge under specified conditionsindicates the depth of the groove at which the maximum sizes of discreet solid particles in theproduct are readily discernible by the unaided eye. The result is critical for, among other things, gloss level and tint strength. It also describes the annual reference check procedure.

2. Apparatus

a) Gauge Blocks and Scraper b) Certified standard grind gauge 0 – 100 microns (for annual reference checks only) c) 4 Test Paints (for annual reference checks only)

3. Procedure

a) Place gauge on flat surface and wipe clean before use. b) Pour small sample of paint, taken in accordance with "sampling procedure" QC work instruction, diluted if necessary using an appropriate resin and/or solvent, into the deep end of the grooves. c) While holding the scraper perpendicular to the gauge surface and at right angles to the length of the groove, draw the scraper down the gauge at a uniform rate to a point beyond the zero mark. Complete this step in 1 to 2 seconds. d) Within a period of 3 seconds inspect the draw down and view the gauge from the side. Determine the position along the groove where the test sample first shows a predominantly speckled appearance. e) Note the position where the sample contains approximately 5 to 10 particles within a band 3-mm wide and identify the two graduations endorsing that band. Estimate the upper position of the band, relative to the larger of the enclosing graduation and record this as the fineness of grind. f) Disregard any isolated specks which may appear prior to the position where the speckled appearance begins. g) If the rheology of the sample is such that a smooth surface is not obtained after draw down, add a minimal quantity of appropriate solvent/binder to the sample, stir and repeat test. Report such thinning. h) Carefully clean the gauge and scraper IMMEDIATELY after the test.

4. Annual Reference Check of Working Gauges

Repeat Procedure a) – h) on both the Calibrated Standard Gauge Block and the working grindgauges listed in section 2 Apparatus. Note the readings and visually compare the results for 4test paints encompasing the gauge block range.

5. Reporting

a) Fill out calibration book noting date of calibration, operators name and reference method. b) All workings / calculations to be shown.

AS ISO/IEC 17025-2005


c) Acceptance Criteria to fall within “Specification” noted on most current Nata Peport filed in this work instruction. If reading falls within acceptance criteria sign “Suitable for Use” If reading falls outside criteria retest and then inform Quality System Co-Ordinator re: corrective action to be implemented. d) No blocking out or liquid paper to be used. Any mistakes to be neatly crossed out and the correct figure to be written and initialled. e) Working grind gauges to be checked annually against certified calibrated standard gauge.

6. Reference

A.S.1580 Method 204.1

FLOW CUP VISCOSITY

1. Introduction

The flow cup measures the consistency of paints that are essentially Newtonian. The method involves measuring the time taken for a certain volume of paint to flow through an orificecentred in the base of a standardised cup.

2. Apparatus

a) B4 Flow Cupb) Stand and Level Barc) Thermometerd) Timer

3. Procedure

a) Bring temperature of cup to around 25°C; ensure cup (including orifice) is totally clean and dry. b) Take sample of paint and adjust temperature to 25°C; immediately proceed with the determination. c) Put cup in stand, level the cup and place finger over the bottom of the orifice. d) Fill cup with paint sample avoiding air entrapment and level off the liquid in the cup by carefully sliding the level bar across the cup rim, sweeping any excess paint into the side rim. e) Place a receiving container under the stand so that the distance between the cup orifice and the receiving container is 150mm, then place a thermometer in the container so as to read the temperature of the test material. f) With timer at the ready, remove the finger from the orifice and activate the timer simultaneously. g) Observe the stream of liquid flowing from the orifice and, at the first appearance of a distinct break in the stream, stop the timer. h) Check the temperature of the sample for variation of temperature +0.5oC. If acceptable, report result in seconds and repeat test. If a variation of greater than 5% occurs, check all equipment. i) Clean all equipment IMMEDIATELY after test. Caution: Metal cleaning tools should not be brought into contact with the inside wall of the orifice or cup -clean orifice with soft brush or cotton bud. 4. Reference A.S. 1580 Method 214.2

AS ISO/IEC 17025-2005


KREBS -STORMER VISCOSITY

1. Introduction

The Stormer viscometer measures the consistency of liquids at a low shear rate. With thisviscometer a paddle, driven by means of falling weights simulates a mild mixing action.

2. Apparatus

a) Stormer Viscometer fitted with stroboscopeb) Thermometer

3. Procedure

a) Take a 500 mL container and fill to at least three-quarters of its capacity with paint sample. b) Adjust temperature of test sample to 25 +/-0.5°C and maintain this throughout the test. c) Place the container on the platform of the viscometer so that the paddle-type rotor is immersed to the mark located on the rotor shaft. d) Determine to the nearest 5 grams the weight necessary to illuminate the two centre bars to a consistent, even green display for at least five seconds. e) Use a grams to K.U. conversion table to determine and report the consistent in Krebs Units. f) Clean paddle and viscometer IMMEDIATELY after the test.

4. Reference

A.S.1580 Method 214.1

SPRAY APPLICATION

1. Introduction

The techniques presented here are designed for Q.C. testing of finish coatings that in practiceare primarily applied by spraying. Spray tests of these paints are particularly pertinent in the process of determining realistic gloss levels, tinter compatibility and surface defects.Primer/undercoat spray paints are also applied as described below, however, proceduresassociated with gloss measurements are ignored.

2. Apparatus

a) Spray Gun as specified by the product data sheet b) One spraycard, and two glass panels (10 cm x 30 cm) -lined with black epoxy for clear finishes; clear opaque finishes. c) Clean, dust-free backing board (no less than 35 cm x 35 cm). e) Dry/wet film thickness gauge/s.

3. Preparation

a) Soak glass panels in a 1% solution of a commercial caustic cleaning formula in fresh boiling water overnight (e.g., 200 mL 'Extra 100' + approx. 10 L boiling water + glass panelsin 20 L bucket). Use a MEK solvent bath for stubborn paints, followed by the hot caustic solutions. b) Scrape and/or scour panels, rinse thoroughly with hot tap water, and allow to drip dry.Repeat whole cleaning process if paint or water marks persist.. AVOID using solvents afterthe hot caustic bath, as even fast evaporating

AS ISO/IEC 17025-2005


solvents will affect the surface tension of the glass.c) Take two glass panels (use black epoxy-lined glass for clear finishes) and a spraycard; label them with the batch number; label one glass panel 'A.D.' (ambient dry), and the other 'O.D.' (oven dry). Wipe glass panels with fresh clean cloth and tape onto a single backingboard (this helps prevent dust contamination).d) Filter sample before spraying to avoid surface defects due to surface tension gradientscreated by foreign particles.

4. Procedure

a) Just immediately prior to spraying, dust panels using pressurised air from spray gun.b) Apply a double or a single double-headed cross coat evenly over entire surface of backingboard which includes the glass panels and the spraycard. Aim to achieve a dry film thickness of 60 +/-10 microns (this usually corresponds to around 120 microns wet film thickness).This is critical, as film thickness can affect gloss level significantly.c) Note unusual surface characteristics of the freshly painted panels. If surface defects suchas cratering or pin holing occur, monitor their behaviour during the first hour of the dryingprocess for the 'A.D.' panel only. If necessary, repeat spraying procedure until satisfied thatthere is indeed a problem with the paint and not the technique.d) Allow 15 minutes solvent evaporation for the panel labelled 'O.D.', before placing it in a 60ºC oven for 30 minutes. Leave the second panel labelled 'A.D.' to dry at ambient room temperature overnight.e) The true and final gloss level is determined using the 'A.D.' panel. Use the 'O.D.' panel only as a rough guide. The gloss level of the 'O.D.' panel is usually about 5-10% higher than that of the 'A.D.' panel. Accurately measuring the film thickness will help make sense of gloss. File the spraycard.f) IMPORTANT: Clean spray gun with MEK (solvent based paints)/water (water basedpaints) immediately after use: rinse solvent through gun, backflush gun with solvent, and thenrinse with about 20 mL fresh solvent by turning gun upside down. Check that air cap is spotless inside-out.

ROLLER APPLICATION

1. Introduction

This procedure is used to determine the suitability of a paint for application by manual rollercoating. It provides for the assessment of defects during and after application of the paint.

2. Apparatus

a) 15-25cm roller with 10mm nap. b) Roller tray. c) Test panel not smaller that 40cm by 50cm (horizontal by vertical) gyprock, placed vertically or nearly vertically. d) Goods quality approx. 38 mm brush. 3. Preparation

a) Refer to product data sheet.

4. Procedure

a) Pour paint into roller tray. Before rolling, brush some paint along the edges of the test panel, taking note of the brushing properties. (see Brushing Application Procedure (b)). b) Proceed to rolling by saturating the roller with the paint in the tray. c) Remove excess paint by rolling on the subsidiary panel. d) Apply paint to the test panel until three quarters of panel is covered as evenly as possible. During application note such properties as rolling, flowing, spreading,levelling, bubbling, sagging, clogging and side slip.

AS ISO/IEC 17025-2005


e) After 5 min recoat two thirds of the panel, noting the ease of difficulty of lapping. e) After the paint has dried for 24 hours examine the lapped area to the single coat for differences in floss or other defects.

5. Reference

AS 1580 method 205.

BRUSH APPLICATION

1. Introduction

This procedure is used to determines the suitability of a paint for application by brushing. Itprovides for the assessment of defects during and after application of the paint.

2. Apparatus

a) Good quality approx. 38 mm brush. b) Test panel, i.e., timber for oil based domestic paints and gyprock for water based domestic paints. c) Spraycards (Doc No.19).

3. Preparation

a) Refer to product data sheet.

4. Procedure

a) Apply the paint to test panel with diagonal criss-cross strokes across a section of the panel. Using the tip of the brush recoat this section with vertical strokes. b) During application note such properties as the brushing, flowing, spreading, levelling and setting up of the material. c) Continue the application, noting the ease of difficulty of lapping until the whole of the panel is coated. d) Allow the paint to dry and examine the area of lapping and that immediately adjacent for deference's in gloss and/or other defects. e) Repeat steps a) to b) but instead use a spraycard as the test panel. Label the card with the product code and batch number and file in the QC filing cabinet. e) Note any other possible defects associates with the dried brushed material (such as thorough-dry and surface appearance) in the test panel and the spraycard.

5. Reference

AS 1580 Method 205.1

SPECULAR GLOSS

1. Introduction

Specular gloss is the ratio (expressed as a percentage) of the luminous flux reflected from, tothat

AS ISO/IEC 17025-2005


incident on, a specimen for a specified solid angle. The sample preparation method inthis procedure is split into two -one for spraying paints, the other for brushing paints -as the two methods of application can result in vastly different gloss levels.

2. Apparatus

a) Sheen photoelectric gloss meter fitted with a 60 degree geometry exposure head. b) Sheen Calibration Plate. c) Two glass panels (10 cm x 30 cm) -lined with black epoxy for clear finishes; clear for opaque finishes. d) Spray gun (spraying paints), as specified by the product data sheet, or 150 micron drawdown bar (brushing paints).

3. Preparation

Spraying paints -see 'Spray Application' of this QC Testing Manual. Brushing paints a) Obtain a clean glass panel (see cleaning instructions under 'Spray Application'); use a black epoxy-lined glass panel for clear finishes (not deep/clear bases). b) Use a 150 micron draw-down bar to cast a sample of the paint on the glass panel. b) If solvent based, allow a 60 minute period for solvent evaporation before curing in 60oC oven for further 30 minute If water based, allow a 40 minute period for solvent evaporation before curing in 60oC oven for further 10 minutes.

4. Procedure

a) Calibrate the instrument at the start and during the operation at sufficiently frequentintervals to check that the instrument response is practically constant.b) Calibration: check the 60° head by placing the instrument onto the black felt area of theSheen calibration plate; pressing the 60° button, adjust the control unit to read zero.c) Place the instrument over the glass calibration section aligning the 60° and 20° calibration markings. Adjust the instrument to give the gloss of the 60° calibration sample. (For 20° head carry out the same procedure but adjust to the 20° calibration sample.) d) Measure the 60°gloss of the test specimen in at least three parts of the panel. (Ifmeasurements are being made on a substrate other than a plate glass panel, they shall betaken in at least five parts of the panel.) e) Report the result as an average of the appropriate readings under the exposure head angleused. e.g. Gloss = 65% / 60° Also report any departures from the method of preparation ofthe test specimen and or any test surface differing in gloss by more than 5 percent of the average gloss of the specimen.

5. Reference

A.S.1580 Method 602.2

BK DRY TIME

1. Introduction

This procedure describes the determination of the "through" dry time using a BK type dryingrecorder. Although this test is primarily intended for solvent based paints, it can, asappropriate, be used to assess the drying and curing characteristics of other paints.

AS ISO/IEC 17025-2005


2. Apparatus

a) BK type drying recorder, fitted with moving pins to produce an effective load of 3.0 to 4.0 grams. NOTE: Current apparatus on premises require no pin weights. b) Glass test panel, cut to 24 mm x 300 mm. c) Film applicator; 76 microns wet film thickness.

3. Preparation

a) Ensure room temperature is between 20°C to 23°C. b) Set the full time scale knob (located on side of recorder) to shortest time possible -6, 12 or 24 hours -according to the paint to be tested; e.g.; two pack polyurethanes generally require the 6 hour time frame, whereas most enamels require the 12 hour time frame. c) Check that pin is completely free of foreign matter, clean if necessary. d) Apply the paint over the full length of glass panel using the film applicator. e) Immediately place glass panel in position on the recorder, locating the pin assembly so that it traces the entire distance in the prescribed time frame; switch in recorder. f) Gently place pin tip in position on the wet film; mark initial position of pin on panel. g) On full completion of the prescribed time frame, mark the end of the last visible tear/break in the paint surface. Using the appropriate time rule located on the side of the recorder, determine the though dry time as dictated by the distance between the two marks. Note that any traces left on the section after the last visible tear/break in the paint surface appears as an indent of decreasing depth; although not considered in the through dry determination, report to Technical Manager if this trace continues beyond time frame limit.

4. Reference

A.S. 1580 Method 401.3. PH

1. Introduction

This section sets out a method for determining the pH of water-based paints and ingredients.The method is considered to be primarily application to paints whose pH falls within anominal range of pH=3 to pH=10. Calibration should be performed daily or more frequently if thought necessary by user. NOTE: Refer to manufacturer's instructions for specific details on operation andmaintenance of the pH instrument and electrode.

2. Apparatus

a) pH measuring instrument, capable of measuring accurately to nearest 0.1 pH unit. b) Clean, maintained pH electrode suited to instrument. c) Two standard pH buffer solutions; preferably pH values bracketing the pH of the test sample, or alternatively pH values very close to the suspected pH of the test sample. d) Reference electrolyte solution suited to pH electrode. e) 2 -3 drops of concentrated HCl in 100 mL of tap water or saturated aqueous KCl solution for pH electrode storage.

3. Calibration and Maintenance

a) Switch instrument on to display pH measurement.

AS ISO/IEC 17025-2005


b) Prepare two buffer solutions in cups (pre-rinsed by small amounts of relevant buffer solution) and allow them to come to room temperature. c) Thoroughly rinse pH electrode under running tap water, shake off excess water and then immerse in the pH buffer solution whose pH is closest to pH=7. Briefly shake electrode, then wait 20-30 seconds for thermal equilibration. d) Press the appropriate keys to calibrate and/or confirm the buffer pH. If an error indication persists, it is likely that the buffer solution of pH electrode is faulty. e) Repeat steps c) to d) for the second buffer solution. f) If the pH electrode is in constant use, store in HCl solution so that organic residues (e.g., latex) dissolve, leaving the glass membrane clean. Never allow electrode to dry out. Store in saturated aqueous KCl for long term storage. g) Ensure that the reference electrolyte is replaced often so that the performance of the pH electrode is not impaired.

4. Measurement – check ph electrode ( before use ) by test reading one buffer solution. a) Switch instrument on to display pH measurement. b) Take sample to be tested in accordance with "sampling procedure" QC work instruction, and bring test sample to room temperature, as per "conditions of test" QC work instruction. c) Thoroughly rinse pH electrode under running tap water, shake off excess water and then immerse in the test sample. Briefly shake electrode, then allow up to 1 minute for the reading to stabilise (as the ingredients of the paint tend to interfere with efficient operation of the glass electrode). Record pH reading to nearest 0.1 pH unit. d) Thoroughly clean pH electrode after use with running tap water. 5. Reference A.S. 1580 Method 505.1. COLOUR MATCHING

1. Introduction

This method describes a procedure for colour matching factory paint batches using either acolour spectrophotometer facility or a visual technique

2. Apparatus

a) Colour reference standard (no less than 5 cm x 10 cm), stores in the refrigerator or QC filing cabinet or some other source b) Spraycard. c) X-Rite colour spectrophotometers – Calibrated externally see Certification. d) Light booth, designs with basic feature described in AS 4004.

3. Preparation

a) Calibrate spectrometer prior to use and every four hours thereafter as per manufacturer's manual. b) Refer to sample preparation chart (work instruction No. 96) for paint sample preparation. c) Coat spraycard as per work instruction "Spray Application" or 'Brush Application", whichever is pertinent, with at least 45 cm x 10 cm surface coverage; oven up to 60°C may be used to facilitate drying.

4. Procedure

AS ISO/IEC 17025-2005


The colour matching of standard factory paint batches is to be finally compared visually asdescribed below. If more that one tinter or a nonstandard tinter (standard tinters to be usedare indicated on Batch Ticket -Production Sheet) are/is required to correct a colour, then thecolour spectrophotometer (operated by the Colour Supervisor or his/her nominee) must beused to generate a correction recipe.

VISUAL COLOUR MATCHING

a) Hold test sample and the reference colour standard 5 mm apart, at arm's length, in the lightbooth set to daylight, 10 cm to 20cm away from the light source. View the surfaceperpendicularly with the light falling on them at about 45° (it is helpful to slightly tilt glossyspecimens away from the observer and to view them at about 45°C to the perpendicular).At 5 mm separation between sample and standard a small colour difference may be seen,when a colour match is acceptable, the colour difference should be undetectable when the separation is increased to 25 mm. According to AS 15803601.1, this degree ofmatching is rated 2 (a "Close Match").b) If metamerism is important, first compare the colour of the test sample with that of thereference standard under daylight illumination and then under a second illumination source pertinent to customer's circumstances, such as a fluorescent light source.c) Colour corrections must first be performed on the laboratory sample, before finallyadjusting and checking colour of full factory batch.

5.0 Reference AS 1580.601.3

AS 4004 and AS 1580.601.1. TARE WEIGHT

1. Introduction

This procedure ascertains the actual total weight of paint made in batches. This procedure isperformed typically where viscosity is not measured or the measured specific gravity is under question.

2. Apparatus

a) Factory weighing scales.

3. Procedure

a) The net weight of paint is determined by subtracting the weight of the vat from the total weight of the vat plus the paint. b) This net weight is recorded onto the production sheet. c) The net weight must be within ± 5 kg of the theoretical weight, regardless of the batch size, in order for the paint to pass.

OPACITY 0.040 BAR

1. Introduction

This procedure provides an approximate measure of the relative opacity between differentbatches of a given paint be drawing a film over a black and white background.

2. Apparatus

a) 0.040um coiled wire draw down bar. b) Spraycard c) Clean flat glass surface with dimensions greater that of the spraycard.

AS ISO/IEC 17025-2005


3. Procedure

a) Record the product code and batch number of the paint onto the spraycard. b) Secure the spraycard to the flat glass surface. c) Place draw down bar at top of card and then pour sufficient paint (unthinned) across the full width of the spray card. d) Draw the 040 bar down into the paint then stop momentarily to allow the paint to fill the voids between the wire on the bar. Steadily and smoothly draw the bar down the card, stopping after the end of the card has been reached. f) Allow spraycard to dry at room temperature. g) Read the L value on the spectrophotometer both over black and over white . h) The paint is satisfactory of its opacity on the spraycard is similar to that of previous batches of the same product. DEGREE OF SETTLING / CALIBRATION OF SPATULA

1. Introduction

This procedure describes the degrees of settling of Evic paints. Nata requires that the settling spatula be :a) Initial calibration – Dimensions and Mass ( See Dimension Report ) b) Six Monthly – Re examine for wear and change.

2. Apparatus :

A steel – bladed spatula with a square end is required, conforming to thefollowing requirementsTotal mass-----------------------------------------50 + 2.5 g Total length---------------------------------------20 cm approx Length of blade to shoulder---------------------12 cm min Width of blade -----------------------------------2.0 cm to 2.5 cm Thickness of blade-------------------------------1.2 + 0.1 mm

3. Procedure

a) Conduct test in accordance with "conditions of test" QC work instruction. b) Lower spatula vertically into the approximate centre of the sample.Note :-Does if fall to the bottom of the container under its own mass within 30 seconds? If not, push the end to the bottom.c) With the end of the spatula on the bottom of the container, move it edgewise and thensideways, noting the resistance offered to such movement. Without lifting the spatula, returnto the approximate centre of the bottom.d) Lift up the end of the spatula from the bottom of the container so as to hold as much of the settled pigment as possible and note the amount and consistency.e) Rate the degree of settling on a numerical scale in accordance with the followingdescriptions

Rating Description

10 Complete suspension of pigment

8 A feel of settling of pigment. No significant resistance to sideways movement of thespatula. A small deposit brought up on the spatula.

6 Definite settled pigments through which the spatula will drop to the bottom of thecontainer within 30 seconds. Definite resistance to sideways movement of thespatula. Appreciable deposit brought up on the spatula..

4 Definite caking of settled pigment through which the spatula will not drop to thebottom of the container within 30 seconds. Difficult to move the spatula through thecake sideways and slight edgewise resistance.

AS ISO/IEC 17025-2005


2 Definite cake of settled pigment through which it is very difficult to move the spatulasideways and offering a definite resistance to edgewise movement.

0 A hard – dry cake of settled pigment. 4 Reporting re: Calibration

a) Fill out calibration book noting date of calibration, operators name and reference method.b) All workings / calculations to be shownc) Acceptance Criteria must equal apparatus requirements as per listed If measurements arecorrect sign “Suitable for Use” If measurements fall outside criteria see Quality System Co-Ordinator re: Corrective Action to be implementedd) No blocking our or liquid paper to be used. Any mistakes to be neatly crossed out and thecorrect figure to be written and initialled. e) Calibration to be conducted six monthly for re-examination for wear and change.

5. Reference A.S 1580 211.1

qc test methods with nata equipment calibration and … · qc test methods with nata equipment...

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