3T Method - Mobile Access Tower Technical Update (Additional Components)

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This will depend upon the final deck height of your Tower, whether the Tower is single or double width, and of course your manufacturer's original spec.

In our experiments, using a double width Boss 1450 Ladderspan Tower, we found significant changes to the quantities of decks and handrails required compared to the pre-WAHR kit list.

In the following table the pre-WAHR spec is shown in brackets, and the shaded columns (9.2m - 11.2m inclusive) are for indoor use only. Notice how the extra decks and braces required for the 3T Method are sometimes included in the pre-WAHR spec already due to the requirements of BS1139, though not always in the correct "mix":

Deck Height>>	1.2m	2.2m	3.2m	4.2m	5.2m	6.2m	7.2m	8.2m
Fixed Deck	1 (1)	1 (1)	2 (1)	2 (1)	2 (2)	2 (2)	3 (2)	3 (2)
Trap Door Deck	1 (1)	1 (1)	2 (2)	2 (2)	2 (2)	2 (2)	3 (3)	3 (3)
Horizontal Brace	6 (6)	6 (6)	10 (8)	10 (8)	10 (10)	10 (10)	14 (11)	14 (11)
Diagonal Brace Starting Position*	1 (Odd)	2 (Even)	1 (Odd)	2 (Even)	1 (Odd)	2 (Even)	1 (Odd)	2 (Even)

Deck Height>>	9.2	10.2	11.2	12.2
Fixed Deck	3 (2)	3 (2)	4 (2)	4 (2)
Trap Door Deck	3 (4)	3 (4)	4 (5)	4 (6)
Horizontal Brace	14 (12)	14 (12)	18 (14)	18 (14)
Diagonal Brace Starting Position*	1 (Odd)	2 (Even)	1 (Odd)	2 (Even)

* see 'Diagonal Braces' for explanation of this

Again, we strongly recommend that you contact your manufacturer for updated assembly instructions/kit lists as soon as possible

Choice of Base Frames >> Positioning of Temporary Handrails >> Additional Components >> Diagonal Bracing >> Fitting Toeboards To Intermediate Deck Levels >> The 3T Method