scope:

This specification relates to high quality black natural rubber compound mixes designated NR MD intended primarily for the manufacture of respirators and their components.

The designation 'type MD' indicates that the materials when correctly vulcanized are suitable for use in certain applications involving contact with the human skin. The choice of ingredients used in the manufacture is therefore controlled and special processing precautions are specified.

NOTE: The new designation of the compound mixes covered by this specification and their relationship to the previous grades are shown in the Annex.