Disclosure to Promote the Right To Information

Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public.

इंटरनेट मानक

“!ान $ एक न' भारत का +नम-ण”Satyanarayan Gangaram Pitroda

“Invent a New India Using Knowledge”

“प0रा1 को छोड न' 5 तरफ”Jawaharlal Nehru

“Step Out From the Old to the New”

“जान1 का अ+धकार, जी1 का अ+धकार”Mazdoor Kisan Shakti Sangathan

“The Right to Information, The Right to Live”

“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता है”Bhartṛhari—Nītiśatakam

“Knowledge is such a treasure which cannot be stolen”

“Invent a New India Using Knowledge”

है”ह”ह

IS 11911 (1986): Caffeine, Food Grade [FAD 8: FoodAdditives]

IS : 11911 - 1986

Indian Standard SPECIFICATION FOR

CAFEEINE, FOOD GRADE

Food Additives Sectional Committee, AFDC 19

Chairman

DR T. S. SANTHANAKRISHNAN’

Members

Representing

Bush Boake Allen ( India ) Ltd, Madras

SHRI B. HANUM~NTHA RAN ( Alternate to DR T. S. Santhanakrishnan )

DR J. C. ANAND All India Food Preservers’ Association, New Delhi DR S. JINDAL ( Alternate )

DR S. S. ARYA Defence Food Research Laboratory ( Ministry of Defence ), Mysore

DR ( SHRI~ATI ) T. S. VASUNDRARA ( Ahmote ) SHRIMATIANITA CHAUDHARY Directorate of Marketing and Inspection, ( Ministry of

SRRI R. J. VERMA ( Alternate ) Agriculture and Rural Development ), New Delhi

SHRI M. V. DESAI Atul Products Limited, Atul DR J. M. TUREL ( .4tt.matc )

BRIG S. K. DEWAN Technical Standardization Committee, Purchase Organization, New Delhi

Army

SHRI K. S. KRISHNAMURTHY ( Alternate ) SARI P. K. DHINGRA Food Research and Standardization Laboratory,

Ghaziabad DRUGS CONTROLLER ( INDIA ) Ministry of Health and Family Welfare, New Delhi

DEPUTY DRUGS CONTROLLER ( INDIA ) ( Alternate )

SERI R. C. GUP~A Directorate General of Technical Development, New Delhi

SHRI S. N. PANDEY ( Alternate ) SHRI R. S. IYER

DR V. S. MOHAN ( Alternate ) Glaxo Laboratories ( India ) Limited, Bombay

SARI J. C. JAISANI Directorate General of Health Services ( Ministry of Health and Family Welfare ), New Delhi

SERIMATI DE~I MUEHERJEE ( Alternate ) DR E. K. JAYANARAYANAN Mohan Meakin Limited, Ghaziabad

SHRI D. K. RASTOGI ( Alternate ) JOINT COMMISSIONER ( DAIRY Department of Agriculture ( Ministry of Agriculture

DEVELOPT.IEXT ) and Rural Development ), New Delhi DEPUTY COMMISSIONER ( DAIRY

DEVELOPMENT ) ( Alternate )

+Dr T. S. Santhanakrishnan acted as chairman at the meeting in which the docu- ment was finalized.

( Continued on page 2 )

@ Cofiyright 1987

BUREAU OF INDIAN STANDARDS

This publication is protected under the Indian Copyright Act ( XIV of 1957 ) and reproduction in whole or in part by any means except with written permission of the publisher shall be deemed to be an infringement of copyright under the said Act.

Is : 11911 - 1986

( Continued from page 1 )

Members Representing

SHRI S. KASTHURI King Institute, Madras PUBLIC ANALYST ( Alternate )

SEKI J. C. KATHRANI Asian Chemical Works, Bombay; and All India Saccharin Manufacturers’ Association, Bombay

DR S. S. PANDIT ( Akern& ) SHRI S. K. K~ANNA Industrial Toxicology Research Centre, Lucknow SHRI V. K. MENON Amar Dye Chemi Limited, Kalyan DR M. J. MULEY Hindustan Lever Limited, Bombay

DR V. R. SHIRHATTI ( Afferna2c ) DR A. G. NAIXX KUR ADE Indian Dehydrated Foods Industries Association,

New Delhi DR B. K. NANDI Foods and Nutrition Board, Department of Food

( Ministry of Food & Civil Supplies ), New Delhi SHRI M. M. KWATARA ( Alternate )

DR C. S. NARAYANAN Regional Research Laboratory ( CSIR ), Trivandrum DR C. ARUMUQHAN ( Alternate )

Da K. M. NARAYANAN National Dairy Research Institute ( ICAR ), Karnal DR M. K. JAIN ( Alternate )

SHBI A. S. RAJADHAYKSHA Corn Products Company ( India ) Pvt Ltd, Bombay Snnr S. R. PALEKAR ( Alternate )

DR R. RAJAGOPALA RAO Central Food Technological Research Institute ( CSIR ), Mysore

DR R. SESHADRI ( Alternate ) SHRI N. RAMAMURTHY Indian Confectionery Manufacturers’ Association,

New Delhi REPRESENTATIVE The Federation of Hotel and Restaurant Association

of India, New Delhi DR A. K. ROY Council for Indian Food Trade and Industry,

New Delhi SHRI D. S. CHADHA ( Alternate )

SHRI M. W. SHENDE Hickson & Dadajee Limited, Bombay SHRI K. P. RANE ( Alternate )

DR I. S. SHENOLIRAR National Institute of Nutrition, Hyderabad DR RAMESH BHAT ( Altemute )

SHRI I. A. SIDDIQI Directorate of Vanaspati, Vegetable Oils & Fats, Ministry of Food and Civil Supplies, New Delhi

DR T. V. SURBAIAH Indian Chemical Manufacturers’ Association, Calcutta

DR R. K. MEHTA ( Alternate ) SHRI s. B. SZTLE Naarden ( India ) Limited, Bombay

SHRI D. B. BEDEI~AR ( Ahernate ) SHRI A. TIWARI Central Salt & Marine Chemicals Research Institute,

Bhavnagar DR R. M. OZA ( Alternate )

DR G. M. TIWARI Britannia Industries Ltd, Bombay DR C. P. S. MENON ( Alternate)

SHRI M. B. TURAEHIA Idachem Industries Pvt Ltd, Bombay SHRI B. J. NAVLOOR ( Alternate )

SHRI P. C. VIN Vin Flavours, Vadodara SHRI T. PURNANANDAM, Director General, BIS ( Ex-qjicio Member )

Director ( Agri & Food )

Secretory

SHRIMATI SEASHI SAREEN Deputy Director ( Agri & Food ), BIS

( Continued on page 11 )

2

IS : 11911- 1986

Indian Standard SPECIFICATION FOR

CAFFEINE, FOOD GRADE .

0. FOREWORD

0.1 This Indian Standard was adopted by the Indian Standards Institution on 28 November -1986, after the draft finalized by the Food Additives Sectional Committee had been approved by the Agricultural and Food Products Division Council.

0.2 With the increased production of processed foods, manufacturers have started adding a large number of substances, generally in small quantities, to improve the appearance, flavour, texture, or storage properties of the processed foods. As certain impurities in these subs- tances could be harmful, it is necessary to have a strict quality control of these food additives. A series of standards is, therefore, being prepared by this Institution to cover purity and identification of these substances. These standards would help in checking purity which requires to be checked at the stage of manufacture for it is extremely difficult ( and in many cases impossible ) to detect the impurity once these substances have been added to the processed foods. Besides, these standards are intended to guide the indigenous manufacturers in making their product conform to specifications that are accepted by scientists, health authorities and international bodies.

0.3 Caffeine is used as a central nervous stimulant in cola-type beverages.

0.4 Chemical Characteristics

0.4.1 Chemical .Name - 1,3,7-trimethylxanthine.

0.4.2 Empirical Formula - C&H,oN402

0.4.3 Molecular Weight - 194.19.

0.4.4 Structural Formula

iH3

3

IS:11911 - 1986

0.5 In the preparation of this standard considerable assistance has been derived from Food Chemical Codex, Pub. National Academy of Sciences and Xational Research Council, Washington, DC, USA.

0.6 For the purpose of deciding whether a particular requirement of this standard is complied with, the final value, observed or calculated, expressing the result of a test or analysis, shall be rounded off in accordance with IS : 2-1960*. The number of significant places retained in the rounded off value should be the same as that of the specified value in this standard.

1. SCOPE

1.1 This standard prescribes the requirements and the methods of sampling and test for caffeine, food grade.

2. TYPES

2.1 The product shall be of the following two types:

a) Anhydrous, and

b) Hydrous.

3. REQUIREMENTS

3.1 Description - Caffeine shall be in the form of a white powder or white glistening needles usually matted together. It shall be odorless and shall have a bitter taste. Its solution shall be neutral to litmus. The hydrate shall be efllorescent in air.

3.2 Identification

3.2.1 Dissolve about 5 mg caffeine in 1 ml of hydrochloric acid in a porcelain dish. _Add 50 mg of potassium chlorate and evaporate on a steam bath to dryness. Invert the dish over a vessel containing a few drops of ammonia solution ( 400 ml of 28 percent ammonium hydroxide diluted to 1 000 ml with water ). The residue shall acquire a purple colour, which disappears upon the addition of a solution of a fixed alkali.

3.2.2 To a saturated solution of caffeine add freshly prepared tannic acid solution ( 1 g of tannic acid dissolved in 1 ml alcohol and water added to make 10 ml ). A precipitate, which is soluble in an excess of the reagent shall be formed.

*Rules for rounding off numerical values ( revised ).

4

IS :11911- 1986

3.2.3 To 5 ml of a saturated solution of caffeine add 5 drops of iodine solution ( 14 g of iodine dissolved in a solution of 36 g of potassium iodide in 100 ml of water, 3 drops of hydrochloric acid added, and solution diluted to 1 000 ml with water and mixed ). No precepitate shall be formed. Then add 3 drops of diluted hydrochloric acid solution ( 10 percent w/c ). A red-brown precipitate, which redissolves on addition of a slight excess of sodium hydroxide solution ( 4.3 g of sodium hydroxide dissolved in water to make 100 ml ), shall be formed.

3.3 Melting Range - The melting range of the sample when dried at 80°C for 4 hours shall be between 235 and 237*5”C.

3.4 The material shall also conform to the requirements given in Table 1.

TABLE 1 REQUIREMENTS FOR CAFFEINE, FOOD GRADE

CIIARACTERISTICS REQUIREPIEKTS METHOD OF TEST, REF TO

r___-h_-__

Appendix ‘Clause of of this IS : 1699- Standard 1974*

k.

(1)

9

ii)

iii)

iv)

v)

vi)

vii)

(2)

Purity (as GHJ%Os) (on anhydrous basis ), percent by mass, Min

Moisture, percent by mass, MUX

a) Anhydrous caffeine

b) Hydrous caffeine

Lead ( as Pb ), mg/kg, Max

Arsenic ( as As ), mg/kg, Max

Heavy metals ( as Pb ), mg/kg,

Readily carbonizable substances

ResmiEegaxignition, percent by ,

(3)

98.5

0.5

8.5

10

3

20

To pass teSt D -

0.1 E -

*Method of sampling and test for food colours (first revision ).

(4) (5)

A -

B -

- 9

- 10

C -

4. PACKING, STORAGE AND MARKING

4.1 Packing and Storage - Hydrous caffeine shall be packed and stored in well closed containers and anhydrous caffeine in tight containers.

5

IS:11911-1986

4.2 Marking - Each container shall be marked legibly to give the following information:

a) Name of the material whether hydrous or anhydrous and including the words ‘food grade’;

b) Name and address of the manufacturer; c) Minimum net mass of contents; d) Batch or code number; and e) Date of manufacture.

4.2.1 The containers may also be marked with the Standard Mark.

NOTE - The use of the Standard Mark is governed by the provisions of the Bureau of Indian Standards Act, 1986 and the Rules and Regulations made thereunder. The Standard Mark on products covered by an Indian Standard conveys the assurance that they have been produced to comply with the requirements of that standard under a well defined system of inspection, testing and quality control which is devised and supervised by BIS and operated by the producer. Standard marked products are also continuously checked by BlS for conformity to that standard as a further safeguard. Details of condittons under which a licence for the use of the Standard Mark may be granted to manufacturers or producers may be obtained from the Bureau of Indian Standards.

5. SAMPLING

5.1 The representative samples of the material shall be drawn and conformity of the material to the requirements of this specification shall be determined according to the procedure prescribed in 3 of IS : 169% 1974*.

6. TESTS

6.1 Tests shall be carried out by the methods specified in co1 4 and 5 of Table 1.

6.2 Quality of Reagents - Unless specified otherwise pure chemicals and distilled water ( see IS : 107O-1977t ) shall be employed in tests.

NOTE - ‘Pure chemicals’ shall mean chemicals that do not contain impurities which affect the results of anal) sis.

*Methods of sampling and test for food colours (first revision ). tspecification for water for general laboratory use ( second rcursion ).

6

I§ : 11911- 1986

APPENDIX A [ Table 1, Item (i) ]

DETERMINATION OF PURITY

A-I. REAGENTS .

A-l.1 Acetic Anhydride

A-l.2 Benzene

A-l.3 Perchloric Acid - O-1 N.

A-2. PROCEDURE

A-2.1 Dissolve about 800 mg, accurately weighed, fine powder caffeine, with warming, in a mixture of 80 ml of acetic anhydride and 180 ml of benzene. Cool and titrate with 0.1 N perchloric acid determining the end-point potentiometrically. Each ml of 0.1 N perchloric acid is equivalent to 19.42 mg of C&&oN&z.

APPENDIX B [ Table 1, Item (ii) ]

DETERMINATION OF MOISTURE

B-l. PROCEDURE

B-l.1 For routine purposes, moisture shall be determined by drying the sample at 120°C for 4 hours. In case of dispute moisture shall be determined by the Karl Fischer method described in IS : 2362-1973*.

APPENDIX C [ Table 1, Item (v) ]

DETERMINATION OF HEAVY METALS

C-l. REAGENTS

C-l.1 Ammonia Solution - Dilute 400 ml of 28 percent [ammonium hydroxide to 1 000 ml with water.

C-l.2 Acetic Acid Solution - 6 percent ( m/u ).

*Method for determination of water by the Karl Fisher method (first rcvi.rion ).

7

IS : 11911- 1988

C-l.3 Hydrochloric Acid - 10 percent.

C-l.4 Lead Nitrate Stock Solution - Dissolve 159’8 mg of lead nitrate Pb ( NOa )2 in 100 ml of water containing .I ml of nitric acid, then dilute with water to 1 000 ml and mix. This solution should be prepared and stored in glass containers which are free from lead salts.

C-l.5 Standard Lead Solution - On the day of use dilute 10 ml of lead nitrate stock solution, accurately measured, with water to 100 ml. Each ml of the solution so prepared contains the equivalent of 10 mg of lead ion ( Pb ).

C-l.6 Hydrogen Sulphide - A saturated solution of hydrogen sulphide made by passing H$ in cold water.

C-2. PROCEDURE

C-2.1 Solution A - Take 1 ml of the standard lead solution in a 50-ml Nessler tube and add water to make 25 ml. Adjust the PH to between 3.0 and 4.0 ( PH indicator paper ) by the addition of diluted acetic acid or ammonia solution. Dilute with water to 40 ml and mix.

C-2.2 Solution B - Make a solution of 500 mg of substance in 2.5 ml of hydrochloric acid and 23 ml of water. Place 25 ml of this solution in a 50-ml Nessler tube that matches the one used for solution A and adjust the pH to between 3.0 and 4’0 (PH indicator paper ) by the addition of dilute acetic acid solution or ammonia solution. Dilute to 40 ml with water and mix.

C-2.3 To each tube add 10 ml of freshly prepared hydrogen sulphide solution. Mix, allow to stand for 5 minutes and view down over a white surface. The colour of solution B shall not be darker than that of solution A.

APPENDIX D [ Table 1, Item (vi) ]

TEST FOR READILY CARBONIZABLE SUBSTANCES

D-l. REAGENTS

D-l.1 Salphuric Acid Solution - Add a quantity of sulphuric acid of known concentration to sufficient water to adjust the final concentrationto between 94.5 and 95.5 percent of HeSOd. Since the acid concentration may change upon standing or upon intermittent use, the concentration should be checked frequently and solutions assaying more than 95.5 percent or less than 94.5 percent discarded or adjusted by adding either diluted or fuming sulphuric acid, as required.

8

IS : 11911 - 1986

D-l.2 Cobaltous Chloride Solution - Dissolve about 65 g of cobaltous chloride ( CoCl2.6HzO ) in sufficient quantity of a mixture of 25 ml of hydrochloric acid and 975 ml of water to make 1 000 ml. Pipette 5 ml of this solution into a 250-ml iodine flask, add 5 ml hydrogen peroxide solution ( a solution containing between 2.5 and 3.5 grams of hydrogen peroxide in each 100 ml and suitable preseryatives, totalling not more than 0.05 percent ) and 15 ml of sodium hydroxide solution ( 1 in 5 ), boil for 10 minutes, cool, and add 2 g of potassium iodide and 20 ml of dilute sulphuric acid ( I in 4 ). When the preci- pitate has dissolved, titrate the liberated iodine with 0’1 Nsodium thiosulphate. The titration is sensitive to air oxidation and should be blanketed with carbon dioxide. Each ml of 0’ 1 X sodium thiosulphate is equivalent to 23.79 mg of CoCl2.6HzO. Adjust the final volume of the solution by the addition of enough of the mixture of hydrochloric acid and -water to make each ml contain 59.5 mg of CoCl2.6HzO.

D-l.3 Cupric Sulphate Solution - Dissolve about 65 g of cupric sulphate ( CuSO+5H20 ) in sufficient quantity of a mixture of 25 ml of hydrochloric acid and 975 ml of water to make 1 000 ml. Pipette 10 ml of this solution into a 250-ml iodine flask, add 40 ml of water, 4 ml of acetic acid, and 3 g of potassium iodide, and titrate the liberated iodine with 0.1 N sodium thiosulphate, adding starch solution ( see D-1.3.1 ) as the indicator. Each ml ofO.1 N sodium thiosulphate is equivalent to 24.97 mg of CuSOa.5HzO. Adjust the final volume of the solution by the addition of enough of the mixture of hydrochloric acid and water to make each ml contain 62.4 mg of CUS0&5H@.

D-1.3.1 Starch Solution - Mix one gram of a suitable starch with sufficient amount of cold water to make a thin paste. Add 20 ml of boiling water. Boil for one minute with continuous stirring and cool. Use only the clear solution.

D-l.4 Ferric Chloride Solution - Dissolve about 55 g of ferric chloride ( FeCls.6H20 ) in sufficient quantity of a mixture of 25 ml of hydrochloric acid and 975 ml of water to make 1 000 ml. Pipette 10 ml of this solution into a 250-ml iodine flask, add 1.5 ml of water, 5 ml of hydrochloric acid, and 3 g of potassium iodide, and allow the mixture to stand for 15 minutes. Dilute with 100 ml of water, and titrate the liberated iodine with 0’1 N sodium thiosulphate, adding starch solution ( see D-1.3.1 ) as the indicator. Perform a blank determination with the same quantities of the same reagents and in the same manner and make necessary correction, if any. Each ml of 0’ 1 3 sodium thiosulphate is equivalent to 27.03 mg of FeC13.6H20. Adjust the final volume of the solution by addition of the mixture of hydrochioric acid and water to make each ml contain 45.0 mg of FeCls.6H20.

9

IS:11911- 1986

D-2. PROCEDURE

D-2.1 Add 500 mg of the sample, finely powdered, in small portions to the comparison containers, which is made of colourless glass resistant to the action of sulphuric acid, containing 5 ml of sulphuric acid solution ( see D-l.1 ). Stir the mixture with a glass rod until solution is complete. The colour should not be darker than the colour produced by mixing in a similar comparison container 0.3 parts cobaltous chloride solution ( see D-l.2 ), 0’6 parts ferric chloride solution ( see D-l.4 ), 0.4 parts cupric sulphate solution ( see D-l.3 ) and 3.7 parts water. The fluids in the tubes are to be viewed transversely against a background of white porcelain or white glass.

APPENDIX E [ Table 1, Item (vii) ]

DETERMINATION OF RESIDUE ON IGNITION

E-l. REAGENTS

E-l.1 Dilute Snlphuric Acid - 10 percent ( m/v ).

E-2. PROCEDURE

E-2.1 Transfer about 2 grams of the sample, accurately weighed, to a tared 50-ml to loo-ml platinum dish or other suitable container and add sufficient diluted sulphuric acid to moisten the entire samples. Heat gently, until the sample is dry and thoroughly charred, then continue heating until all the sample has been volatilized or nearly all of the carbon has been oxidized. Cool. Moisten the residue with 0’1 ml of sulphuric acid, and heat in the same manner until the remainder of the sample and any excess sulphuric acid have been volatilizi?d. Finaliy ignite in a muffle furnace at 800 & 25°C for 15 minutes. Cool in a desiccator and weigh.

E-3. CALCULATION

Residue on ignition, percent by mass = $$- x 100

where

Ml = mass in g of residue, and

.M = mass in g of the material taken for the test.

10

IS:11911- 1986

( Continued from page 2 )

Food Colours and Flavours Subcommittee, AFDC 19 : I

CO7U??l.H

SHRI K. V. NA~ARAJA

Representing

Central Food Laboratory_, Central Food Tech- nological Research Inststute ( CSIR ), Mysore

Members .

DR J. C. ANAND All India Food Preservers’ Association, New Delhi DR S. JIXDAL ( Alternate )

SHR1S.D. BH~RDWAJ Ajanta Chemical Industries, New Delhi Sam KAPIL DEV ( Alternate )

SHRI VAT DEV BHARDWAJ Arun Chemical Industries, New Delhi SHRI ASHOE DO~RA ( Alternate )

SHRI P. K. DH~N~RA Food Research and Standardization Laboratory, Ghaziabad

SERI M. K. JAIN National Dairy Research Institute ( ICAR ), Karnal SHRI J. C. JAISANI Directorate General of Health Services, Ministry of

Health and Family Welfare, New Delhi SHRIMATI DEBI MUKHERJEE ( Alternate )

SHRI S. KASTHURI King Institute, Madras DR S. K. KHANNA Industrial Toxicology Research Centre, Lucknow SHRI S. M. MEHTA Atul Products Limited, Atul

SHRI M. V. DESAI ( Alternate ) SHRI V. K. MENON Amar Dye Chemi Limited, Kalyan DR M. J. MULKY Hindustan Lever Limited, Bombay

DR V. R. SHIRHATTI ( Alternate ) DR A. G. NAIK KURADE Indian Dehydrated Foods Industries Association,

New Delhi Srmr B. A. RANE Hickson & Dadajee Limited, Bombay

SHRI M. W. SHENDE ( Ahmnte ) SERI B. HANOZ~NTHA RAU Bush Boake Allen ( India ) Limited, Madras

DR T. S. SANTHANAKRISEEAN ( Alternate ) DR L. V. L. SASTRY Central Food Technological Research Institute

( CSIR ), Mysore SHRINAVINCRANDRA R.SHAH Devarsons Private Limited, Ahmadabad

DR V. K. MEHTA ( Alternate ) SHRI S. B. SULE Naarden ( India ) Limited, Bombay SHRI S. C. VASUDEVAN Corn Products Co ( India ) Pvt Ltd, Bombay

SHRI S. R. PALEKAR ( Altemnte ) SHRI P. C. VIN Vin Flavours, Vadodara

I1

INTERNATIONAL SYSTEM OF UNITS ( SL UNITS )

Base Units

QUANTITY

Length

Mass

Time

Electric current .

Thermodynamic temperature

Luminous intensity

Amount of substance

Supplementary Units

QUANTITY

Plane angle

Solid angle

Derived Units

QUANTITY

Force

Energy

Power

Flux

Flux density

Frequency

Electric conductance

Electromotive force

Pressure, stress

UNIT

metra

kilogram

second

ampere

kelvin

candela

mole

UNIT

radian

steradian

UNIT

newton

joule

watt

weber

tesla

hertz

siemens

volt

Pascal

SYMBOL

m

kg S A

K

cd

mol

SYMBOL

rad

sr

SYMBOL

N

J w Wb

T

HZ

S

V

Pa

DEFINITION

1 N = 1 kg.m/s”

1 J = 1 N.m

1 W = 1 J/s

lWb=lV.s

1 T = 1 Wb/m*

1 Hz = 1 c/s (s-s)

1 s = 1 A/V

1 V = 1 W/A

1 Pa = I N/ma

.