Schedule XVII

USE OF OVENS AND DRIERS IN FACTORIES

1. Application- This schedule shall apply to ovens and driers, except those used in

laboratories and kitchens of any establishment and those which have a capacity below 325

litres.

2. Definitions- For the purpose of this schedule, "oven or drier" means any enclosed

structure, receptacle, compartment or box which is used for baking, drying or otherwise

processing of any article or substance at a temperature higher than that ambient temperature of

air in the room of space in which the oven or drier is situated, and in which the flammable or

explosive mixture of air and flammable substance is likely to be evolved with the enclosed

structure, receptacle, compartment or box or part thereof on account of article or substance

which is baked or dried or otherwise processed within it.

3. Separate electric connection- Electric power supplied to every oven or drier shall be by

means of separate circuit provided with an isolated switch.

4-. Design, construction, examination and testing- (1) Every oven or drier shall be properly

designed on sound engineering practice and be of good construction, sound materials and

adequate strength free from any patent defect and safe, if properly used.

(2) No oven or drier shall be taken into use in factory for the first time unless a competent

person has thoroughly examined all its parts carried out the tests as are required to establish

that the necessary safe systems and control provided for safety in operation for the processes

for which it is to be used and a certificate of such examination and tests signed by that

competent person has been obtained and are kept available for inspection.

(3) All parts of an oven or drier has undergone any alteration or repair which has the effect

of modifying any of the design characteristics, shall not be used unless a thorough examination

and tests as have been mentioned in clause (b) have been carried by the competent person and

a certificate of such examination and tests signed by that competent person has been obtained

and are kept available for inspection.

5. Safety, Ventilation- (1) Every oven or drier shall be provided with a positive and

effective safety ventilation system using one or more motor driven centrifugal fans so as to

dilute any mixture of air and flammable substance that may be formed within the oven or drier

and maintain the concentration of the flammable substance in the air at safe level of dilution.

(2) The safe level of dilution referred to in clause (a) shall be so as to achieve a concentration

of concerned flammable material in air of not more than 25 % of its lower explosive limit;

Provided that level of concentration in the air up to 50% of the lower explosive limit of the

concerned flammable substance may be permitted to exist subject to installation and

maintenance of an automatic device which:-

(a) Shows continuously the concentration of the flammable substance in air present in the

oven or drier at any instant;

(b) Sounds an alarm when the concentration of the flammable substance in air present in

any part of oven or drier reaches a level of 50% of explosive limit

(c) Shuts down the heating system of the oven or drier automatically when the

concentration of the flammable substance in air present in any part of oven or drier reaches a

level of 60% of lower explosive limit, is provided to the oven or drier and maintained in the

efficient working condition.

(d) No oven or drier shall be operated without its safety ventilation system working

inefficient manner.

(e) no oven or drier shall be operated with a level of dilution less than whatis referred in

clause (b)

(f) exhaust ducts of safety ventilation system should be so designed and placed that their ducts

discharge the mixture of air and flammable substance away from the workroom and not near

windows or doors or other openings from where the mixture could re-enter the work room.

(g) The fresh air admitted into the oven or drier by means of safety ventilation system shall

be circulated adequately by means of circulating fans or fans through all parts of the oven or

drier so as to ensure that there is no location where the flammable substance can accumulate in

the air become pocketed to any dangerous degree.

(h) Throttling dampers in any safety ventilation system should be so designed by cutting away

the portion of damper or otherwise that system will handle at least the minimum ventilation

rate required for safety when they are set in their maximum throttling position.

6. Explosion panels - (1) every oven or drier having an internal total space of not less than

half cubic meter shall be provided with suitably design explosion panel so as to allow the

release of the pressure of any possible explosion within the oven or drier through explosions

vents. The area of opening of any access doors which are provided with suitable arrangements

for their release in case of an explosion shall not be less than2200 sq cm for every 1 cum of the

volume of the oven or drier. The design of the explosion panel and doors as stated above shall

be such as to secure their complete release under an internal pressure of 0.25 kg/sq cm.

(2) The explosion releasing panel shall, as far as practicable, be situated on the roof of the oven

or drier or at those portions of the walls where persons don't remain in connection with

operation of oven or drier.

7. Inter locking arrangement - In each oven or drier efficient inter locking arrangement

shall be provided and maintain to insure that

(a) All ventilating fans and circulating fans whose failure would adversely effect the ventilation

rate of flow pattern, are in operation before any mechanical conveyor that may be provided for

feeding the article or substances to be processed in the oven or drier, input into operation

(b) Failure of any of the ventilating or circulating fans will automatically stop any conveyor

as referred to in clause (a) as may be provided as well as so the fume supply by closing the shut

of valve and shut off the ignition in the case of gas or oil fired ovens and in case of electrically

heated oven switch off the electrical supply to the heater.

(c) The afore-said mechanical conveyor is set in operation before the said shut off valve

can be energies

(d) The failure of the aforesaid conveyor will automatically closed the said shut off valve

in the case of oven and drier heated by gas, oil or steam and deactivate the ignition system or

cut off the electrical heater in the case of electrically heated ovens are furnaces

8. Automatic ventilation; - Every oven or drier heated by oil, gas, steam or electricity shall be

provided with an efficient arrangement for automatic

ventilation consisting of at least three volume changes with fresh air by operation of safety

ventilation fans and circulating fans so as to effect purging of the oven or drier of any mixture

of air and flammable substance before the heating system can be activated and before the

conveyor can be placed in position.

9. Temperature control - Every oven or drier shall be provided with an automatic

arrangement to ensure that the temperature which does not exceed a maximum temperature

required in respect of the particular process is being carried out

10. Multi stage processes - Whatever material are to be processed in ovens or driers in

successive operation suitable arrangements should be provided to ensure that the operating

temperature necessary for safe operation at each stage are maintain within the design limit

11. Combustible substances not to drip on electrical heater or burner flame

Effecting arrangement shall be provided in every oven or drier to prevent dripping of

combustible substances on electrical heater or burner flame used for heating.

12. Periodical examination, testing and maintenance - (a) All parts of every oven or drier

shall be properly maintain and thoroughly examined and the various control as mentioned in

the schedule and the working of the oven or drier shall be tested at frequent interval to ensure

its safe operation by a responsible person authorized by the occupier or manager in this behalf

who by his experience and knowledge of necessary precaution against risk of explosion, is fit

to undertake such work

(b) A register shall be maintained in which the details of various tests carried out from time to

time under clause (a) shall be entered and every entry shall be signed by the person making the

test.

13: - Training of operator - No person shall be assigned any task connected with operation of

any oven or drier unless his has completed 18 yrs. of age and is properly trained.

14. Polymerizing machine - (a) Printed fabric shall be thoroughly dried by passing them over

drying canes or through hot flue or other equally effecting means before the same is allowed

to pass through polymerizing machines

(b) Infra ray heater of polymerizing machines shall be cut off while running the print.