Refinishing can give a tub new life however exposure to the hazardous chemical
methylene chloride used in the process can end a life. Workers can be exposed
to methylene chloride - a colorless solvent - by inhaling it or absorbing it
through their skin - and the results can be deadly. According to NIOSH, since
2000 at least 14 worker deaths have been linked to the use of stripping
products containing methylene chloride in bathtub refinishing. Exposure to as
little as 6 ounces (177.4 mL) of a methylene-chloride based product has been
enough to cause death. OSHA and NIOSH recently issued a hazard alert to warn
bathroom refinishers of the dangers associated with methylene chloride.
Although the solvent has a sweet smell, the odor is noticeable only at levels
above OSHA's permissible exposure limits and the ACGIH® Threshold Limit Value
(TLV®), so by the time workers smell it they have already been overexposed. In
addition, workers can quickly become desensitized to the odor and may be
overexposed even if they can no longer smell it.

Health effects

Exposure to methylene chloride can cause dizziness, fatigue, headaches, nausea
and eye, nose and throat irritation. Higher exposures can stop breathing, and
cause coma and sudden death. Once in the body, methylene chloride forms carbon
monoxide. Carbon monoxide reduces the oxygen-carrying capacity of the blood,
eventually depriving the body of oxygen. Workers with pre-existing heart
conditions may be more susceptible to the effects of carbon monoxide. Long-term
exposure to methylene chloride may cause cancer.

Methylene chloride is highly volatile, easily entering the air, and the vapor
can rapidly accumulate in the air of small, enclosed spaces, like a bathroom.
It can even displace oxygen in the air, leaving an insufficient amount for
breathing.

Worker protection

• Use products that do not contain methylene chloride or use products with a minimal amount of the solvent.


• Consider alternative methods such as sanding to remove old finishes; take precautions to minimize or reduce inhalation of particulate produced by sanding.


• If products containing methylene chloride are used, the workplace air must be tested for methylene chloride. Airborne levels must be kept below applicable occupational exposure guidelines - permissible exposure limits (PELs) or threshold limit values (TLVs).

Workers must be trained on the hazards of working with products containing
methylene chloride and what precautions to take, for example:

• avoid spraying methylene chloride-based products, and leave the room immediately after application to minimize exposure;


• ensure adequate ventilation; ventilating with a bathroom fan is not sufficient


• wear appropriate personal protective equipment, such as respirators, gloves and eye protection; and


• use long-handled tools to avoid leaning into bathtubs.

These products will contain additional ingredients which may present additional
hazards. Consult the Safety Data Sheet for information on all of the hazards
and control measures relevant to the product.

More information:

AplusA-online.de - Source: Canadian Centre for Occupational Health and Safety