1 Scope
1.1 This method involves laboratory test steps over a period of two weeks to simulate possible settlement of road sign paint in normal storage for approximately 12 months.

1.2 This standard is expressed in IN-1B units and the values given in parentheses are for reference only.

1.3 This standard is not intended to address all safety issues, even if they are addressed, only those related to their use. The responsibility of this STANDARD to the user is to develop applicable safety and health practices and determine the adaptive capacity of their control areas prior to the adoption of this standard. For safety provisions, see clause 5.2.

ASTM D 1309-1993 Settlement of Road Sign Paint in Storage

2 Reference Documents
2.1 ASTM Standard

D 869 Standard test method for evaluating the settlement of road signs

3 Significance and application
3.1 Excessive precipitation may occur if the paint is not prepared or treated in the correct way. In order to evaluate the settlement performance of the road sign paint in 2 weeks, the purpose of this test is to find the conditions that can accelerate the settlement. The combination of this very subjective method of assessment with the variables of test method D 869 gives rise to the practical question of whether the test results meet the requirements of the code.

4 Instruments
4.1 Container standard 500mL capacity, friction top cover (can be painted) container, diameter (85.5 ± 1.5)mm, height (98.5 ± 1.5)mm.

4.2 The scraping spoon weighs about (45±1)g, with a square edge, 125mm in length and 20mm in width. It can be obtained by cutting the tip of 125mm elastic steel scraper commonly used in the laboratory to the prescribed length.

4.3 Keep the refrigerator at -21 ~ -23.3 ℃

4.4 Keep the oven at (160±2) % ℃

4.5 Lid clamp

ASTM D 1309-1993 Settlement of Road Sign Paint in Storage

5 Test procedures
5.1 Effectively mix the paint to be evaluated to a uniform consistency. Pour enough paint into a 500mL paint bucket. Make the height within 13mm from the top of the barrel. Close THE PAINT bucket TIGHTLY with a LID with 4 clips and subject it to the following exposure cycle.

5.1.1 Monday to Friday:

(1) Put in the refrigerator at 8:00 am;

(2) Transfer to oven at 10:00 am;

(3) Transfer to the refrigerator at 2:00 PM;

(4) Transfer to oven at 4:00 PM.

5.1.2 From 4:00 PM Friday to 8:00 am Monday:

(1) Friday at 4:00 PM in the oven;

(2) At 8:00 a.m. on Monday, after the paint bucket passes in the oven over the weekend, it is placed in the refrigerator and continues the cycle for another 7 days as described above. Each time the paint bucket is taken out of the oven and placed on the table, it is violently slapped on the table top, which makes the bottom of the bucket form an instantaneous and rapid shaking against the table top. This strong shaking can make the bottom of the bucket hit not against the table top but against the table top of the scale plate, and the scale plate can be weighed about 2.27kg.

5.2 At the end of exposure, the coating was allowed to cool for 4h at room temperature and its settlement was determined according to D869.

5.2.1 Note – Open the paint barrel slowly and carefully to release the residual steam.

ASTM D 1309-1993 Settlement of Road Sign Paint in Storage

6 Reports
Report accelerated settlement evaluation according to D869.

7 Precision and deviation
7.1 Accuracy — The accuracy of test method D 869 is not high, and if it is used in the specification, the maximum deviation from the specified precipitation limit value should be agreed between the purchaser and the seller.

7.2 Bias — Such bias cannot be determined.