وفقا لمفتش السلامة، مطفأة الحريق منتهية الصلاحية.

وفقًا لـ is a very common formal expression meaning according to or in accordance with.

So:

• وفقًا لمفتش السلامة = according to the safety inspector

The لِـ is part of this fixed expression. You normally say:

• وفقًا لِ... = according to ...
• طبقًا لِ... = according to ...
• استنادًا إلى ... = based on ...

So لمفتش is not random here; it is required by وفقًا.

If fully vocalized, this part is often written as وفقًا لمفتشِ السلامةِ.

Because مفتش السلامة is an iḍāfa construction, often called a genitive or annexation construction.

Structure:

• مفتش = inspector
• السلامة = safety
• مفتش السلامة = safety inspector

In an iḍāfa:

• the first noun usually does not take الـ
• the whole phrase becomes definite if the second noun is definite

So:

• مفتش سلامة = a safety inspector
• مفتش السلامة = the safety inspector

That is why the English translation uses the.

Yes. مطفأة الحريق is also an iḍāfa.

Breakdown:

• مطفأة = extinguisher
• الحريق = the fire
• مطفأة الحريق = fire extinguisher

Literally it is something like the extinguisher of the fire, but in natural English we say the fire extinguisher.

Just as with مفتش السلامة, the phrase is definite because the second noun is definite:

• مطفأة حريق = a fire extinguisher
• مطفأة الحريق = the fire extinguisher

Because Arabic often uses a nominal sentence in the present tense, with no separate word for is/are.

So:

• مطفأة الحريق منتهية الصلاحية
• literally: the fire extinguisher expired/out of date
• natural English: the fire extinguisher is expired

In present-time statements, Arabic usually leaves out the equivalent of is.

Compare:

• الجو جميل = the weather is nice
• المدير مشغول = the manager is busy
• مطفأة الحريق منتهية الصلاحية = the fire extinguisher is expired

If you wanted past tense, then Arabic would use a verb such as كانت:

• كانت مطفأة الحريق منتهية الصلاحية = the fire extinguisher was expired

Because it agrees with مطفأة, and مطفأة is a feminine noun.

So:

• masculine: منتهي
• feminine: منتهية

Since the subject is مطفأة الحريق, the predicate appears in the feminine singular form:

• مطفأة الحريق منتهية الصلاحية

This kind of agreement is very common in Arabic. Adjectives and predicate adjectives usually match the noun in gender and number.

Idiomatic meaning:

• منتهية الصلاحية = expired, out of date, no longer valid for use

Literal idea:

• منتهية comes from a verb meaning to end or to come to an end
• الصلاحية means validity, fitness for use, or period of usability

So the phrase suggests that the item’s valid usable period has ended.

This expression is very common for:

• food
• medicine
• official documents
• equipment that has a validity or inspection period

So in this sentence, it means the fire extinguisher is no longer within its valid service period.

This is part of a set expression. منتهية الصلاحية is commonly treated like a fixed phrase meaning expired.

You can think of it as a compact construction meaning:

• of expired validity
• or more naturally, with its period of validity ended

In practice, learners should recognize منتهي/منتهية الصلاحية as one unit of meaning.

Examples:

• دواء منتهي الصلاحية = expired medicine
• بطاقة منتهية الصلاحية = an expired card
• مطفأة الحريق منتهية الصلاحية = the fire extinguisher is expired

A fully vocalized version would be:

وفقًا لمفتشِ السلامةِ، مطفأةُ الحريقِ منتهيةُ الصلاحيةِ.

A quick case breakdown:

• وفقًا: accusative adverbial form in this fixed expression
• لمفتشِ: genitive because of the preposition لِـ
• السلامةِ: genitive as the second term of iḍāfa
• مطفأةُ: nominative, because it is the subject of the nominal sentence
• الحريقِ: genitive as the second term of iḍāfa
• منتهيةُ: nominative, because it is the predicate
• الصلاحيةِ: genitive within the construction منتهية الصلاحية

In normal everyday writing, these short vowels are usually omitted.

Yes, it is fairly formal and very natural in Modern Standard Arabic.

A few features that make it feel formal:

• وفقًا لـ is a formal reporting expression
• مطفأة الحريق is a standard MSA term
• منتهية الصلاحية is a formal, official-sounding phrase

In spoken Arabic, people might use different wording depending on the dialect. For example, a colloquial equivalent in some varieties might use a more everyday word for fire extinguisher, such as طفاية حريق instead of مطفأة الحريق.

So this sentence is excellent MSA, especially for reports, inspections, or official communication.

Yes. Arabic allows some flexibility.

The given sentence starts with the source of information:

• وفقًا لمفتش السلامة، مطفأة الحريق منتهية الصلاحية.
• According to the safety inspector, the fire extinguisher is expired.

You could also say:

• مطفأة الحريق منتهية الصلاحية، وفقًا لمفتش السلامة.

Both are understandable. The original version sounds especially natural if you want to foreground whose judgment this is.

Starting with وفقًا لمفتش السلامة sets the frame first, which is common in formal Arabic.