shvet
Petroleum
- Aug 14, 2015
- 692
Hello, forum
Please help me in understanding of this issue. One often sees voids in tables. This situation mostly concerns US-issued literature. For example see the extract from NFPA
See - Ester of Acetic Acid and tBuOH has not Zone Group and MESG both while Acrolein has Zone Group and has not MESG.
In the same situation some sources contains dashes and voids both - some positions in a table are fiiled with dashes, some - voids. I have checked several resources - authors provided no legend or logic, so a logic is not obvious.
What does it mean? When a table contains dashes and voids both what a dash mean and what a void? Why not just to specify "n/a" (not available, not applicable) or "n/n" "not known"? Why NFPA did not specified dashes instead of voids - it is more convenient as a reader loses a row less easier. Can anyone please describe this US practice?
Hope my idea is clear.
Please help me in understanding of this issue. One often sees voids in tables. This situation mostly concerns US-issued literature. For example see the extract from NFPA
See - Ester of Acetic Acid and tBuOH has not Zone Group and MESG both while Acrolein has Zone Group and has not MESG.
In the same situation some sources contains dashes and voids both - some positions in a table are fiiled with dashes, some - voids. I have checked several resources - authors provided no legend or logic, so a logic is not obvious.
What does it mean? When a table contains dashes and voids both what a dash mean and what a void? Why not just to specify "n/a" (not available, not applicable) or "n/n" "not known"? Why NFPA did not specified dashes instead of voids - it is more convenient as a reader loses a row less easier. Can anyone please describe this US practice?
Hope my idea is clear.