Guidance for Using Masks in MBL Work Areas

Updated 4/29/21

With narrow exceptions, a face mask covering the mouth and nose must be worn indoors and outdoors when within 6 feet of others.  A face mask must:

  • Fit snugly around the nose and chin with no large gaps around the side of the face
  • Be secured with ties, ear loops, or headbands
  • Cloth masks must be made of multiple layers of tightly woven fabric that does not let light pass through when held up to a light source.
  • Not include exhalation valves or vents.
  • When working with hazardous materials, disposable masks should be used.  Disposable masks are available for purchase in the MBL Stockroom.

Individuals can remove face coverings if they are in a private room/office alone with the door shut or while eating indoors (including designated breakrooms) or in outdoor tent spaces with at least 8 feet of social distance.

When putting on and taking off a mask, do not touch the front of it.  You should only handle the ties or ear straps.  Also, you should be careful not to touch your eyes, nose, and mouth when removing your mask.  Immediately wash your hands or use hand sanitizer after touching the mask.

Cloth masks should be washed regularly using warm water and regular laundry detergent in a washing machine, or hand washed with soap or hand wash detergent.  After lathering, the mask should sit in hot water for 30 minutes.

If you have any questions or concerns, please contact Eric Jensen (EHS Manager) at 508-289-7424 or by email at

MBL-branded masks can be purchased through the Gift Shop.

See links below for additional information on how to properly wear a cloth face covering or mask.

Advisory Regarding Face Coverings and Cloth Masks (MA Department of Public Health)