Pronunciation of “SUS” in “Stainless Steel SUS 304”

How do engineers and the like who are native speakers of English pronounce “SUS” (stainless steel)?

Like the verb “suss” (ie as an acronym)?

Like “SOS” (mayday) but with “U” (ie as an initialism)?

This is incredibly niche in terms of usage. One company might use it as an acronym while another will use it as an initialism. The term SUS (Steel Use Stainless) is only used in Japan Industrial Standard (JIS) and there are talks about it being phased out.

Acronym is when the initials are pronounced as a word. Some examples:

• NATO (Nay-Toe)
• NASA (Nah-Sah)
• GUI (Gooey)
• FIFA (Fee-Fa)
• IRRI (Eery)
• AWOL (Aye-Wall)

Initialism is when the initials are pronounced:

• CEO (See, Ee, Oh)
• IRS (Eye, Ar, Ess)
• TV (Tee, Vee)
• CIA (See, Eye, Aye)
• NSA (En, Ess, Aye)

To answer you question, though (with knowledge that this might be a unique occurrence and that it might differ from place to place), the most logical pronunciation (as an English native speaker) is:

suss.

This would be in favor as it is one syllable as oppose to three in the initialism use.

There are various other standards for steel grades.

The Society of Automotive Engineers (SAE) standard is the most accepted form of defining steel grade. SAE also maintains the UNS standardization. SAE is most common used globally, followed by the British Standards Institution (BSI).

ISO (ISO/TS 4949:2003) standard has been widely adopted as another form of defining stainless steel grades that do not use the US or British standards.

ISO/TS 4949:2003 sets out rules for the designation of internationally standardized steel grades by means of symbolic letters and numbers to express application and principal characteristics (e.g. mechanical, physical, chemical) so as to provide an abbreviated identification of steel grades.

The AISI standardized system, which is pronounced "I-see", from the American Iron and Steel Institute, has also been deprecated and authority given to SAE.