depends on the grounds but generally just no militrary style camo clothing and no sleeveless vests torn clothing etc . just clean casual
These are the official rules from cpsa booklet
18.3 DRESS STANDARDS At all CPSA events described above, competitors’ clothing will be expected to be in a tidy and clean condition and should not contain any messages, images or slogans that may reasonably cause offence to others. Offensive messages or images of a sexual or racial nature are specifically forbidden, as well as any that break accepted standards of decency and good taste. The byword for the standard to be achieved will be: ‘smart/casual’. Listed below are specific examples of personal appearance or garments that will be considered unacceptable under this Code: a) Nakedness of the trunk or limbs other than lower arms or legs. B) Wearing of shooting vests over naked flesh. c) Shirts or tops that have sleeves that when measured from the armpit seam are less than 10cm long (other than shooting vests). d) Cut-off jeans or trousers or any type of shorts other than tailored *shorts. e) Torn, slashed or shredded shirts, jeans, trousers or skirts. f) Military or camouflaged wear, balaclava helmets or camouflage paint. g) Any excessively worn, dirty or dishevelled clothing or footwear. h) Any other garments or personal appearances that go against the spirit of this Code or that seek to exploit any possible loophole within it, at the discretion of the persons named in paragraph 18.2 above.
id say you should go to a clay ground wearing them and see . 
