Service Life of Fire Apparatus
The apparatus can remain in service for up to thirty years as a second line pumper providing it meets the annual pump testing requirements.
Annex D of NFPA 1901 and now in NFPA 1906 gives guidance on when fire apparatus should be placed in reserve status. It states, "Because the changes, upgrades, and fine tuning to NFPA 1901 since 1991 have been truly significant, especially in the area of safety, fire departments should seriously consider the value (or risk) to fire fighters of keeping pre-1991 editions of NFPA 1901 fire apparatus in first-line service."
The annex provides more detailed information on the rationale and the various safety factors incorporated. So essentially, if your fire apparatus was not constructed to these standards, then there is reduced safety for your fire service members. A risk benefit analysis should be undertaken and a replacement schedule identified.
Now what does this mean regarding fire apparatus specified to the ULC standard? As the ULC S-515 Edition was first produced in 1988, it would therefore not include the safety features incorporated in the NFPA 1901 1991 edition. Only subsequent amendments would have addressed these. Vehicle manufacturers would, however, have considered many of these improvements regardless of what was specified in the ULC standard. So any apparatus specified to the ULC standard should be compared to the safety components introduced in the NFPA edition starting in 1991 and retirement considerations should be based on this.
Information on the Fire Underwriters Survey can be found here.