It depends whether there is a posibility of disturbance. If not then the face masks are redundant but if, as I suspect there might, be a chance of disturbance the issuing of face masks alone is not appropriate. Fibres can be carried on the clothing and spread e.g. home for washing. For me if they are advising control measures it must be the full suite of asbestos controls and not just immediate protection of the breathing zone during point of exposure.

If the material has been identified as high risk, immediate action, then it is not only whether the workers intend to disturb the material, but whether it is possible to. Previous posters advice is good. Get advice from your asbestos surveyor, but it does rather sound like remedial action is required. If this is the case then potentially every entry to the plant room by your operators may result in exposure which is reportable under RIDDOR.

Hi there I personnally would ask to their Asbestos Management Plan before I allowed any of my staff to enter this plant room. The plan should detail that actions that should be or should have been undertaken following the asbestos survey. If the cleint is stating it is high risk and immediate action required, this action could possibly be removal by licensed asbestos contractor and air clearance certficates required prior to entering the area. If the client is asking you to wear FFP3 masks, this may indiacte they beleive the fibres are airborne. Like KevKel said the fibres wont just be inhaled they will also be on clothing etc. I think the first step would be to request sight of the asbestos management plan to undertand exactly what you are dealing with here.