Limitaciones del tratamiento trombolítico

Guidance on the classification of areas relating to several specific occupancies is given in AS/NZS 2430.3 (all Parts). For the specific occupancies mentioned in Clauses 3.14.2 to 3.14.7, the requirements of this Clause (3.14) shall apply as appropriate.

3.14.2 Ovens

Electrically heated Type 1 ovens in which flammable volatiles occur shall be verified as complying with and installed in accordance with AS 1681. The ovens shall be certified as set out in Clause 2.6.

3.14.3 Fuel dispensing

Fuel dispensers shall be manufactured and verified as complying with the appropriate Part(s) of AS 2229 and NZS 6109.

3.14.4 Finishing processes

3.14.4.1 Spray and spray/bake booths 3.14.4.1.1 General

Spray painting booths shall comply with the design, construction and testing requirements of AS/NZS 4114.1 and the installation requirements of AS/NZS 4114.2.

3.14.4.1.2 Compliance

Proof of compliance shall be demonstrated by a certificate of conformity issued by a national certification body accredited by JAS-ANZ for product certification in accordance with AS/NZS 4114.1, or by other means acceptable to the Authority.

3.14.4.1.3 Installation and maintenance

Spray painting booths shall be installed and maintained in accordance with AS/NZS 4114.2. The manner in which this work is undertaken shall not reduce the electrical safety or explosion protection afforded by the equipment design or associated equipment such as motors, light fittings, control boxes and sensing devices.

NOTE: The method of installation should pay particular attention to the explosion protection properties of explosion-protected electrical equipment (termed Ex equipment) including certification conditions that may be included on the Ex certification.

3.14.4.1.4 Associated rooms

Associated rooms such as paint mixing and paint preparation rooms shall be correctly installed and maintained in accordance with this Standard.

3.14.4.2 Fixed electrostatic equipment

Where fixed electrostatic spraying and deterring equipment is installed, such equipment shall comply with the following requirements:

(a) High voltage grids or electrodes shall be—

(i) located in suitable non-combustible booths or enclosures provided with adequate interlocked mechanical ventilation;

(ii) rigidly supported and of substantial construction; and

(iii) effectively insulated from earth by means of suitable insulators. (b) High voltage leads shall be—

(i) effectively and permanently supported on suitable insulators; (ii) effectively guarded against accidental contact or earthing; and

(iii) provided with automatic means for discharging any residual charge to earth when the supply voltage is interrupted.

(c) Goods being processed shall be supported on conveyors so that the minimum clearance between goods and high voltage grids or conductors cannot be less than twice the sparking distance. A visible and legible sign indicating the sparking distance shall be permanently located near the equipment.

(d) Suitable automatic controls shall operate without time delay to disconnect the power supply and to signal the operator in the event of any of the following occurrences: (i) Stoppage of ventilating fans or failure of ventilating equipment from any cause. (ii) Stoppage of the conveyor carrying goods through the high voltage field.

(iii) Occurrence of an earth or of an imminent earth at any point on the high voltage system.

(iv) Reduction of clearance below that specified in Item (c).

(e) Adequate fencing, railings or guards which are electrically conducting and earthed shall be provided for safe isolation of the process.

(f) Signs shall be permanently mounted designating the process zone as dangerous because of high voltage.

AS/NZS 2381.1:1999 44

COPYRIGHT 3.14.4.3 Electrostatic hand sprayguns

Electrostatic hand sprayguns shall be used only within a spray booth or approved spray area. Electrostatic hand sprayguns and equipment, and devices used in connection with paint spraying operations shall be of a suitable type and shall comply with the following requirements:

(a) The equipment shall be designed so that the maximum surface temperature of the equipment in the spraying area cannot exceed 65°C under any condition.

(b) The electrostatically charged exposed elements of the spraygun shall be capable of being energized only by a switch which also controls the paint supply.

(c) Transformers, power packs, control equipment, and all other electrical portions of the equipment, with the exception of the spraygun itself and its connections to the power supply, shall be located outside the hazardous area.

(d) The handle of the spraygun shall be electrically connected to earth by a metallic connection.

NOTE: This requirement is to prevent build-up of a static charge on the operator’s body.

(e) All electrically conductive objects in the spraying area shall be effectively earthed, including paint containers, wash cans and any other objects or devices in the area. The equipment shall carry a prominent permanently installed warning explaining the necessity of such earthing.

(f) Objects being painted shall be maintained in metallic contact with the conveyor or other earthed support. To ensure an effective and continuous contact—

(i) hooks shall be regularly cleaned;

(ii) areas of contact shall be sharp points or knife edges where possible;

(iii) points of support of the object shall be concealed from random spray where feasible; and

(iv) where objects are being sprayed and supported from a conveyor the point of attachment to the conveyor shall be located so as not to collect spray material during normal operation.

(g) The spraying operation shall take place within a spray area that is adequately ventilated to remove solvent vapours released from the operation. The electrical equipment shall be interlocked with the ventilation of spraying areas so that the equipment cannot be operated unless the ventilation fans are in operation.

3.14.4.4 Powder coatings 3.14.4.4.1 General

The hazard rating associated with the application of finely ground particles of protective finishing material in dry powder form is dependent upon the chemical composition of the material, particle size, shape and distribution. Hazards associated with both combustible dusts and vapours are inherent in this process and electrical equipment shall—

(a) be of a type suitable for use in Zone 1 and Zone 21 areas; and (b) comply with Clause 3.14.4.3(e).

3.14.4.4.2 Application

Coating powders shall be applied by means of— (a) fluidized bed;

(b) electrostatic fluidized bed; (c) powder spraygun; or

3.14.4.4.3 Fixed and hand electrostatic spraying equipment

Fixed and hand electrostatic spraying equipment for the application of powder coatings shall comply with Clauses 3.14.4.2 and 3.14.4.3.

3.14.4.4.4 Electrostatic fluidized beds

Electrostatic fluidized beds shall satisfy the following requirements:

(a) Electrostatic fluidized beds and associated equipment shall be of an approved type. (b) The maximum surface temperature of such equipment in the coating area shall not

exceed 65°C.

(c) The high voltage circuits and exposed electrodes shall not produce a spark sufficient to ignite any powder mixture or create an appreciable shock hazard upon coming in contact with an earthed object under normal operating conditions.

The following additional requirements shall be satisfied when powder coating is carried out with electrostatic fluidized beds:

(i) Transformers, power packs, control equipment and other electrical portions of the equipment, except for charging electrodes and their connections to the power supply, shall be located outside the powder coating area or shall otherwise conform to the requirements of Clause 3.14.4.4.1.

(ii) All electrically conductive objects in the charging influence of the electrodes shall be adequately earthed. The powder coating equipment shall carry a prominent, permanently installed warning explaining the necessity for earthing these objects.

(iii) Objects being coated shall be maintained in contact with the conveyor or other support in order to ensure proper earthing. To ensure effective contact, hangers shall be regularly cleaned and areas of contact shall be sharp points or knife edges where possible.

(iv) The electrical equipment shall be interlocked with a ventilation system so that the equipment cannot be operated unless the ventilation fans are in operation. 3.14.4.4.5 Use of metal floor ducts to enclose wiring

Metal floor ducts may be used only for supplying ceiling outlets for extensions to the area below the floor of the hazardous area, but such ducts shall have no connections leading into or through the hazardous area above the floor unless suitable seals are provided in accordance with Clause 3.8.14.

3.14.5 Flammable medical agents

The criteria for the minimizing of combustion hazards arising from medical use of flammable anaesthetic agents shall be as set out in AS 1169.

3.14.6 Laboratory fume cupboards

The criteria for the installation of fume cupboards in laboratories shall be as set out in AS/NZS 2243.8.

3.14.7 Secondary batteries in buildings

Secondary batteries in buildings shall be installed, tested, maintained and replaced in accordance with AS 2676.1, AS 2676.2, AS 3011.1 and AS 3011.2.