A slash (/) is used:
- to replace per in expressions of rate or concentration
120 km/h 4 t/ha 3 g/mL
- to replace for in expressions of rate or concentration
wt/wt wt/vol
1/4 y = 3.5/(a + b)
- in the expression and/or; however, this is awkward and ambiguous, and should be avoided if possible. In most cases where a writer has used and/or, it is possible to use and with no loss of meaning:
Environmental reporting can occur at the local, regional, state and territory and/or national levels.
becomes
Environmental reporting can occur at the local, regional, state and territory, and national levels.
- in URLs to mark the end of the protocol (usually 2 slashes are used)
- in URLs to indicate a directory
/a [closing tag of a hyperlink] /font [closing tag of a font element] /p [closing tag of a paragraph element]
Do not use a slash to indicate a ratio or spans of years:
1:3 not 1/3
2010–12 not 2010/12
Slashes are sometimes used to indicate a financial year. An en dash is recommended instead:
2003–04 financial year not 2003/04 financial year
Avoid using a slash to combine terms, such as administrator/supervisor or general practitioner/specialist. Readers have to work hard to decide what the slash means (and or or), and this can sometimes be critical to the meaning. Instead, give the alternatives in full, recasting the sentence, if necessary:
The administrator/supervisor should be informed.
becomes
The administrator and supervisor should be informed.
or
The administrator or supervisor should be informed.
or
It may be necessary to consult either the administrator or the supervisor, or, in some circumstances, both.
The phase I/phase II trials showed …
becomes
The phase I and phase II trials both showed …
Sometimes a slash is used (incorrectly) to replace an en dash:
The doctor/patient relationship
means
The doctor–patient relationship
but is better written as
The relationship between the patient and the doctor
Similarly:
cost–benefit ratio not cost/benefit ratio
dose–response study not dose/response study
To refer to the plural as an alternative to the singular, use parentheses around the s, rather than using a slash:
representative(s) not representative/s
