So Singapore has a law on joss sticks

Environmental Public Health Act
(Chapter 95, Section 113)

Environmental Public Health (Burning of Joss Sticks and Candles) Regulations

Prohibition of burning of joss sticks or candles exceeding certain height or cross section

2. No person shall set or keep alight, or cause or permit to be set or kept alight —
(a) any joss stick which has —
(i) a total height exceeding 2,000 mm; or
(ii) a cross section with a length or diameter at its widest exceeding 75 mm; or
(b) any candle which has a total height exceeding 600 mm.

Restriction of burning of joss sticks or candles exceeding certain height or cross section

3.—(1) Except as provided in paragraph (2), no person shall set or keep alight, or cause or permit to be set or kept alight —
(a) any joss stick which has —
(i) a total height exceeding 700 mm but not exceeding 2,000 mm;
(ii) a cross section with a length or diameter at its widest exceeding 50 mm but not exceeding 75 mm; or
(b) any candle which has a total height exceeding 500 mm but not exceeding 600 mm.

(2) Any owner or occupier of any of the premises specified in paragraph (3) may, in or on those premises, set or keep alight, or cause or permit to be set or kept alight not more than —
(a) 6 joss sticks as described in paragraph (1)(a); and
(b) 2 candles as described in paragraph (1)(b).

(3) The premises referred to in paragraph (2) are —
(a) the enclosed part of any building;
(b) any temple or other place of worship; and
(c) any other premises which is situated at least 30 metres away from any building.

(4) For the purposes of this regulation —
“a cross section with a length or diameter at its widest”, in relation to any joss stick, means the distance between the farthest points on the largest cross-sectional area of the joss stick;
“enclosed part of any building” means any part of a building that has a ceiling or roof, and is, except for doors and passageways, completely enclosed by walls or windows.

Penalty

4. Any person who contravenes regulation 2 or 3(1) shall be guilty of an offence and shall be liable on conviction to a fine not exceeding $2,000.