Anthracite must be able to perform filtration　and cleaning in the filtration pond in a stable　and efficient manner,　and must comply with the regulations of 1.1 main component, 1.2 quality (physical properties)　and 1.3 quality (leaching property).

1. Principal component　and quality

1.1 Main component
The main component of anthracite is crushed high-quality anthracite coal, which has the highest carbonization,　and is made into sand granules.

1.2 Quality (physical properties)
Quality (physical properties) shall be tested according to JWWA A 103-2: 2006-2 6.4.1-6.4.3　and shall comply with the provisions of Table 1.

1.3 Quality (exudability)
Quality (exudability) shall be tested according to JWWA A 103-2: 2006-2 6.5　and shall comply with the provisions of Table 1.

● Table 1-Quality

item		Quality regulations	Applicable test clause
Physical properties	density (g/cm3)	1.40 ～ 1.69	JWWA A 103-2:6.4.1
	Abrasion rate (%)	3.0　or less	JWWA A 103-2:6.4.2
	Hydrochloric acid solubility (%)	6.0　or less	JWWA A 103-2:6.4.3
Exudative	taste	Not abnormal	JWWA A 103-2:6.5
	Odor	Not abnormal
	Saturation (degree)	0.5　or less
	Turbidity (degree)	0.2　or less
	Iron　and its compounds (mg/L)	0.03　or less
	Manganese　and its compounds (mg/L)	0.005　or less

2. Appearance　and dimensions

2.1 Appearance
Appearance shall be tested according to JWWA A 103-2: 2006-2 6.6.1　and comply with the provisions of Table 2.

2.2 Dimensions
The dimensions shall be tested according to JWWA A 103-2: 2006-2 6.6.2　and comply with the provisions of Table 2　and the requirements set by the purchaser.

●Table 2-Appearance　and dimensions

item		Appearance　and dimensions	Applicable test clause
appearance	appearance	Fine powder, flat, scaly　or crushed stone, peat　and other contaminants with low content	JWWA A 103-2:6.6.1
Size	Effective diameter (mm)	0.7 ～ 1.5	JWWA A 103-2:6.6.2
	Equal coefficient	1.5　or less
	Maximum diameter (mm)	2.8　or less
	Minimum diameter (mm)	0.5　or more

Quote: Japan Water Works Association Standard JWWA Water Supply Filter Material A-103: 2006-2
Revised on March 30, 2006