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Rule 15 Coating processes, including spray painting

http://www.gw.govt.nz/rule-15-coating-processes-including-spray-painting

Rule 15 Coating processes, including spray painting

Updated 3 July 2015 12:55pm

The discharge of contaminants into air in connection with coating processes (including spray painting) involving:

(1)the spray application of coating materials (including paint, paint solvents, varnish, lacquer, dyes, metal oxide coatings, adhesive coatings, elastomer coatings, stains, and polishes) at a rate of consumption not exceeding 30 litres (or 30 kg) per day and also not exceeding 3 litres (or 3 kg) per hour on a coating premises;

(2)the spray application of coating materials (including paint, paint solvents, varnish, lacquer, dyes, metal oxide coatings, adhesive coatings, elastomer coatings, stains, and polishes) at any rate of consumption where the application is from a mobile source;

(3)the stoving of enamel or baking and drying of any other coating material where the rate of heat input into the process is less than 500 kW (measured by the higher heating value of the input fuel); or where 500 kW or less of electrical energy is used; and/or

(4) materials that do not contain di-isocyanates or organic plasticisers;

is a Permitted Activity, provided the activity complies with the conditions below.

Conditions

The person responsible for the activity shall ensure that:

(i)there is no discharge of particulates of a concentration greater than 250 mg/m (at STP), measured at the point of discharge;

(ii)no contaminant is discharged from the process, that is noxious, dangerous, offensive or objectionable, at or beyond the boundary of the property;

(iii)for coating processes undertaken indoors, the discharge of contaminants to air is vented with an unimpeded vertical flow, through a chimney(s) or vent(s) which terminates at least three metres above the level of any adjacent area to which there is general access (i.e., ground level, roof areas or adjacent openable windows) and as far as practicable from the boundary of any residential property.

Note: The painting of roadways (road marking) and bridges is a permitted activity covered by Rule 22.

Explanation:Rule 15 relates to the discharge of contaminants to air resulting from coating processes, including spray painting, subject to compliance with the specified conditions. This Rule applies regardless of whether or not the coating process is undertaken as part of a industrial or trade process. Coating processes include the spraying of paints and lacquers, and coating with electrostatic powders. Rule 15 does not apply to discharges to air associated with the application of substances containing di-isocyanates or organic plasticisers. These discharges are either permitted under Rule 14, subject to conditions; otherwise they are discretionary activities under Rule 23. Rule 15 does not cover the painting of roadways (road marking) and bridges, which are permitted activities (Rule 22).

Spray coating processes include processes involving the spray application of paints, paint solvents, varnish, lacquer, dyes, metal oxide coatings, adhesive coatings, elastomer coatings and stains and polishes. For the application phase of the coating process, this rule only relates to the application of these substances by methods involving spraying. Application of paints by paint brushes is a permitted activity regardless of the size of the area being painted, because this activity does not result in the discharge of contaminants to air of any consequence. Thirty litres of paint, if applied by an airless spray unit (no atomising air), can cover approximately 480 m-540 m. An air assisted spray unit can cover approximately 300 m. The spraying of paints or lacquers in suspension can result in problems of over-spray and dust, and solvent fumes.

Electrostatic powder coating is a process whereby dry particles are charged electrostatically to a high voltage and then deposited upon the surface of an earthed object. The primary difference with other forms of spray painting is that powders are applied as fine particles in a dry condition, whereas paint is sprayed as a suspension in a solvent base. While electrostatic powder coating does not cause the same types of problems as spraying, it does result in the discharge of fine powders, which can be injurious to humans if inhaled. Wet paint can be applied electrostatically, through some over-spraying still occurs. Electrostatic coating can also give rise to dust explosions.

Stoving, baking or drying of enamel or other coating material is necessary to ensure that the enamel, paints or lacquers are hardened and fixed to the surface of an object. Stoving, baking and drying of enamel or other substances typically occurs in the ceramics and metal production/finishing industries, such as in the finishing of stoves.

Processes involving the application of 30 litres (or 30 kg) or more of coating materials per day and/or 3 litres (or 3 kg) or more per hour, and stoving, baking or drying related to any coating process where 500 kW or more of heat is released, are discretionary activities under Rule 23.

The conditions in Rule 15 require that there is no discharge of particulates of a concentration greater than 250 mg/m 3 (at STP), measured at the point of discharge, and that there are no noxious, dangerous, offensive, or objectionable discharges of contaminants beyond the boundary of the property. Condition (iii) is aimed at ensuring against fugitive emissions and minimising the adverse effects from downwash.