Special Mark Buoy

Introduction :

Special Mark Buoy is used to indicate a special area or feature whose nature may be apparent from reference to a chart or other nautical publication. It is not generally intended to mark channels or obstructions where other marks are more suitable.

Special mark buoy can be used to show the following:

– Ocean Data Acquisition Systems (ODAS) marks
– Traffic separation marks where use of conventional channel marking may cause confusion.
– Spoil Ground marks
– Military exercise zone marks
– Cable or pipeline marks
– Recreation zone marks
– Boundaries of anchorage areas
– Structures such as offshore renewable energy installations
– Aquacultures.

Description :

Special Mark	Special Mark Buoy
Colour	Yellow
Buoy Shape	Optional but not conflicting with navigational marks
Topmark (if any)	Single yellow ‘X’ shape (St Andrew’s Cross)
Light Colour (when fitted)	Yellow
Light Rhythm (when fitted)	Any other than those described in cardinal, isolated danger and safe water marks

Specification :

Model	Diameter (mm)	Buoying Depth (mm)	Freeboard (mm)	Focal Plane Height (mm)	Net Weight (kg)	Height (mm)	Reserve Buoyancy (kg)
SM800	800	2-10	45	1580	195	2628	230
SM1200	1200	3-15	510	2040	550	3380	570
SM1500	1500	4-20	632	2524	681	4300	1012
SM1800	1800	6-30	722	3031	1686	5134	1546
SM2100	2100	8-40	800	3518	1900	5757	2450
SM2400	2400	10-50	920	4040	2973	6930	4015
SM3050	3050	15-60	1114	5164	3490	9610	7646
SM3500	3500	20-70	1240	6090	3863	8520	11380

Hall Thickness		Mooring Chain		Sinker Specification		The Maximum swaying angle≤15°
Buoy (m)	Thickness (mm)	Buoy (m)	Mooring Chain (mm)	Buoy (m)	Sinker (t)
1.2	10	1.2	17.5	1.2	0.5-1
1.5	10	1.5	22	1.5	1-1.5	Sunproof grade:8
1.8	15	1.8	28	1.8	2-3
2.4	15	2.4	32	2.4	3-6
3	15	3	38	3	5-8