(1) For the purpose of preserving order in relation to traffic when there is an event attracting a large assembly of persons or when there is traffic congestion or a fire, flood or similar occurrence, a member of the Garda Síochána in uniform may do all or any of the following things: divert, regulate and control traffic and regulate and control the parking of vehicles.
(2) The powers conferred by subsection (1) of this section shall, in particular, include power to do all or any of the following things by oral or manual direction or by the use of portable signs of such size, form and colour and having such significance as may be prescribed:
(a) prohibit the passage of traffic;
(b) indicate the direction in which traffic is to proceed;
(c) prohibit the parking of vehicles;
(d) indicate places for the parking of vehicles or as standsfor public service vehicles and regulate their use;
(e) make any other prohibitions or indications which he considers necessary for preventing obstruction
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