What is expiration date of first alert fire extinguishers mfg in 1990?

Answer 1

If properly inspected and maintained, a portable fire extinguisher should not expire. However, it may become obsolete or may outlive various regulations, depending upon whether it is being used commercially.

For example, fire extinguisher technicians will generally not approve an extinguisher that is more than about 7 years old unless it is a type that can be dismantled, emptied, cleaned, inspected, tested and recharged for re-certification.