250 R.I. Code R. 250-RICR-40-20-10.8

Current through December 26, 2024

Section 250-RICR-40-20-10.8 - Investigational Allowances

A. A commercial fertilizer shall be deemed deficient if the analysis of nutrient is below the guarantee by an amount exceeding the values in the following schedule, or if the overall index value of the fertilizer is below ninety-eight percent (98%) following § 10.8(A)(2) of this Part.

Guarantee Percent	Nitrogen Percent	Available Phosphoric Acid, Percent	Potash Percent
4 or less	0.49	0.67	0.41
5	0.51	0.67	0.43
6	0.52	0.67	0.47
7	0.54	0.68	0.53
8	0.55	0.68	0.60
9	0.57	0.68	0.65
10	0.58	0.69	0.70
12	0.61	0.69	0.79
14	0.63	0.70	0.87
16	0.67	0.70	0.94
18	0.70	0.71	1.01
20	0.73	0.72	1.08
22	0.75	0.72	1.15
24	0.78	0.73	1.21
26	0.81	0.73	1.27
28	0.83	0.74	1.33
30	0.86	0.75	1.39
32 or more	0.88	0.76	1.44

1. For guarantees not listed, calculate the appropriate value by interpolation.

2. For these investigational allowances to be applicable, the recommended AOAC procedures for obtaining samples, sample preparation and analysis must be used. These are described in Official Methods of Analysis of the Association of Official Analytical Chemists, 11^th edition (1970), incorporated above at § 10.2(A) of this Part, and in succeeding issues of the Journal of the Association of Official Analytical Chemists. In evaluating replicate data, table 19, page 935, Journal of the Association of Official Analytical Chemists, Volume 49, No. 5 (October 1966), incorporated above at § 10.2(C) of this Part, should be followed.

3. Averaging at least two (2) values must be adhered to. If more than two (2) values are obtained, all significant values must be averaged. Values carried to two (2) decimals are needed in applying averages to this table. Values may be "rounded" to one (1) place where preferred in reporting.

4. The overall index value is calculated by comparing the commercial value guaranteed with the commercial value found. Unit values of the nutrients used shall be those referred to in § 10.7(A)(4)(a) of this Part.

Overall index value example of calculation for a 10-10-10 grade found to contain 10.1% total nitrogen (N), 10.2% available phosphoric acid (P2O5), and 10.1% soluble potash (K2O); nutrient unit values are assumed to be $3 per unit N, $2 per unit P2O5, and $1 per unit K2O:

10.0 units N	x3=	30.0
10.0 units P2O5	x2=	20.0
10.0 units K2O	x1=	10.0
Commercial Value Guarantee	=	60.0
10.1 units N	x3=	30.3
10.2 units P2O5	x2=	20.4
10.1 units K2O	x1=	10.1
Commercial Value Found	=	60.8
60.8
Overall index value =	X	100=101.3%
60.0

B. Secondary and minor elements shall be deemed deficient if any element is below the guarantee by an amount exceeding the values in the following schedule:

Element	Allowable Deficiency
Calcium	0.2 unit + 5% of guarantee
Magnesium	0.2 unit + 5% of guarantee
Sulfur	0.2 unit + 5% of guarantee
Boron	0.003 unit + 15% of guarantee
Cobalt	0.0001 unit + 30% of guarantee
Molybdenum	0.0001 unit + 30% of guarantee
Chlorine	0.005 unit + 10% of guarantee
Copper	0.005 unit + 10% of guarantee
Iron	0.005 unit + 10% of guarantee
Manganese	0.005 unit + 10% of guarantee
Sodium	0.005 unit + 10% of guarantee
Zinc	0.005 unit + 10% of guarantee
The maximum allowance when calculated in accordance to the above shall be 1 unit (1%).

250 R.I. Code R. 250-RICR-40-20-10.8

Amended effective 1/5/2022