25 does not specificaly seem to address wax heads
from 13::
6.2.6 Special Coatings.
6.2.6.1* Corrosion Resistant.
6.2.6.1.1 Listed corrosion-resistant sprinklers shall be installed in locations where chemicals, moisture, or other corrosive vapors sufficient to cause corrosion of such devices exist.
6.2.6.1.2* Unless the requirements of 6.2.6.1.3 are met, corrosion-resistant coatings shall be applied only by the manufacturer of the sprinkler and in accordance with the requirements of 6.2.6.1.3.
6.2.6.1.3 Any damage to the protective coating occurring at the time of installation shall be repaired at once using only the coating of the manufacturer of the sprinkler in the approved manner so that no part of the sprinkler will be exposed after installation has been completed.
are they dry heads or wet heads???
5.3 Testing.
5.3.1* Sprinklers.
5.3.1.1* Where required by this section, sample sprinklers shall be submitted to a recognized testing laboratory acceptable to the authority having jurisdiction for field service testing.
5.3.1.1.1 Where sprinklers have been in service for 50 years, they shall be replaced or representative samples from one or more sample areas shall be tested. Test procedures shall be repeated at 10-year intervals.
5.3.1.1.1.1 Sprinklers manufactured prior to 1920 shall be replaced.
5.3.1.1.1.2 Sprinklers manufactured using fast-response elements that have been in service for 20 years shall be replaced, or representative samples shall be tested. They shall be retested at 10-year intervals.
5.3.1.1.1.3* Representative samples of solder-type sprinklers with a temperature classification of extra high 325°F (163°C) or greater that are exposed to semicontinuous to continuous maximum allowable ambient temperature conditions shall be tested at 5-year intervals.
5.3.1.1.1.4 Where sprinklers have been in service for 75 years, they shall be replaced or representative samples from one or more sample areas shall be submitted to a recognized testing laboratory acceptable to the authority having jurisdiction for field service testing. Test procedures shall be repeated at 5-year intervals.
5.3.1.1.1.5* Dry sprinklers that have been in service for 10 years shall be replaced, or representative samples shall be tested. They shall be retested at 10-year intervals.
5.3.1.1.2* Where sprinklers are subjected to harsh environments, including corrosive atmospheres and corrosive water supplies, on a 5-year basis, sprinklers shall either be replaced or representative sprinkler samples shall be tested.
5.3.1.1.3 Where historical data indicate, longer intervals between testing shall be permitted.
5.3.1.2* A representative sample of sprinklers for testing per 5.3.1.1.1 shall consist of a minimum of not less than four sprinklers or 1 percent of the number of sprinklers per individual sprinkler sample, whichever is greater.
5.3.1.3 Where one sprinkler within a representative sample fails to meet the test requirement, all sprinklers within the area represented by that sample shall be replaced.
5.3.1.3.1 Manufacturers shall be permitted to make modifications to their own sprinklers in the field with listed devices that restore the original performance as intended by the listing, where acceptable to the authority having jurisdiction.