Asbestos Maintenance Worker Refresher Go To Meetings Webinar. Student must have cell phone, tablet, or computer to attend. This Asbestos Operations and Maintenance Refersher training is an annual refresher course for individuals who perform operations, maintenance and repair activities which may disturb minor quantities of ACM, PACM or asbestos material. This course is designed primarily for custodial and maintenance personnel and individuals in the building trades. Operation and Maintenance certification permits the holder to perform OSHA Class III and IV asbestos work only on minor asbestos projects.