law: 3. Incidence of tax.
  (1) Every dealer whose turnover during the year immediately preceding the commencement of this Act exceeds the taxable quantum and every denier who at the commencement of this Act, is registered or is liable to pay tax under the Central Sales Tax Act, 1956 (74 of 1956), shall be liable to pay tax under this Act on all sales effected by him on or after such commencement.
  (2) Every dealer to whom sub-section (1) does not apply, shall
  (i) with effect from the date immediately following the day on which his turnover calculated from the commencement of any year first exceeds within such year the taxable quantum, be liable to pay tax under this Act on all sales effected by him after that day;
  (ii) if he becomes liable to pay tax under the Central Sales Tax Act, 1956 (74 of 1956) or is registered as a dealer under the said Act at any time after the commencement of this Act, be liable to pay tax on all sales effected by him or on his behalf within Delhi on or after the date he becomes so liable or is registered under the said Act, whichever is earlier.
  (3) Every dealer who has become liable to pay tax under this Act shall continue to be so liable until the expiry of three consecutive years during each of which his turnover has failed to exceed the taxable quantum and such further period after the date of such expiry as may be prescribed and on the expiry of such further period his liability to pay tax shall cease:
  Provided that any dealer may, after the expiry of one year following the year in which his turnover has failed to exceed the taxable quantum, apply for the cancellation of his certificate of registration, and on such cancellation, his liability to pay tax shall cease:
  Provided further that in respect of any goods purchased by any dealer before the date of such cancellation and remaining unsold or unutilised for the purpose for which they were purchased, he shall be liable to pay so much of tax as would have been payable had he not been registered as a dealer on the date of purchase of such goods.
  (4) Every dealer whose liability to pay tax under this Act has ceased under sub-section (3), shall, if his turnover calculated from the commencement of any year again exceeds the taxable quantum on any day within such year, be liable to pay such tax with effect from the date immediately following the day on which his turnover first exceeds the taxable quantum, on all sales effected by him after that day.
  (5) Any dealer whose certificate of registration has been cancelled under sub-section (3) of section 20, shall
  (a) if his turnover calculated from the date of cancellation of such certificate exceeds the taxable quantum on any day within the year; or
  (b) if his turnover calculated from the commencement of any subsequent year, exceeds the taxable quantum on any day within the year,
  be liable to pay tax under this Act with effect from the date immediately following the day on which such turnover again first exceeds the taxable quantum on all sales effected by him after that day of goods imported by him from outside Delhi or manufactured by him in Delhi or purchased by him without payment of tax leviable under this Act.
  (6) No dealer who deals exclusively in one or more classes of goods specified in the Third Schedule shall be liable to pay any tax under this Act.
  (7) For the purposes of this Act, "taxable quantum" means,
  (a) in relation to any dealer who imports for sale any goods into Delhi. . . . . Nil,
  (b) in relation to any dealer who manufactures goods for sale regardless of the value of goods manufactured . . . . . . . . . Rs. 30,000.00,
  (c) in relation to any other dealer . . . . . . Rs. 1,00,000.00:
  Provided that if the Administrator is of opinion that having regard to the difficulty in maintaining accounts or for any other sufficient cause the taxable quantum in respect of any class of dealers falling under clause (b) should be increased, the Administrator may, by notification in the Official Gazette, fix in respect of such class of dealers such taxable quantum, not exceeding rupees one lakh, as may be specified in the notification.
  Explanation.
  For the purposes of computation of taxable quantum under sub-section (7), the turnover of all sales effected by a dealer shall be taken into account irrespective of whether such sales are taxable under this Act or not.