How soon must a NOTICE OF EXPIRATION be relayed to the correct parties?

The correct choice indicates that a NOTICE OF EXPIRATION must be communicated to the relevant parties within a timeframe of 30 days. This timeframe is important because it ensures that all parties involved are given ample notice regarding the impending expiration, allowing them sufficient time to make necessary arrangements, whether that involves renewal or replacement. Proper notification is crucial in maintaining compliance with regulations concerning extinguishers, as it helps prevent lapses in safety measures. Following this guideline ensures that emergency equipment is on hand and fully operational when needed, thereby adhering to safety standards laid out in extinguishing statutes and rules.