I interpreted this section that each manifold should have (2) headers and that each header shall have no fewer than (2) connections thus the smallest manifold  header bar set would be 2X2. 

In the last few weeks I have run into two different Architects that are challenging my interpretation and believe a total of (2) connections is sufficient thus 1X1 would be acceptable.

I am interested in how others interpret this section and what they see enforced as the minimum number of cylinder connections.

Thanks

5.1.3.5.12.4 The manifolds in this category shall consist of the

following:

(1) Two equal headers in accordance with 5.1.3.5.10, each

with a sufficient number of gas cylinder connections for

one average day’s supply, but not fewer than two connections,

and with the headers connected to the final line

pressure regulator assembly in such a manner that either

header can supply the system