A BRIEF LESSON IN THE ECONOMICS OF FURNITURE STRIPPING

After years of study and testing, the Occupational Safety and Health Administration of the Federal Government (OSHA) has ordered that the allowable quantity of methylene chloride in the air we breathe be drastically reduced to a threshold limit value (TLV) averaging 25 parts per million (ppm) or less over an 8 hour work day. This order has resulted in a significant increase in the cost of stripping furniture with methylene chloride.

This order applies to shops having employees. If it is a one man or family operated shop, the order does not apply. This is not to say that OSHA is not concerned about family health; it is just that family or one-man shops aren't covered by the rule.

A shop with employees must install ventilating systems designed to maintain methylene chloride levels in the workplace at 25 ppm or less. Very few, if any, existing shops are capable of achieving this goal. Reduction of methylene chloride in the breathing zone to less than 25 ppm will require a properly designed stripping tray ducted to an exhaust fan drawing as much as 4000 to 5000 cubic feet of air per minute (CFM), In addition, water washing booths (if used) will need to be redesigned with proper ventilation. If sneeze curtains are employed, compliance may be achieved with an exhaust fan drawing as little as 2000 CFM.

Drying furniture is a significant source of methylene chloride vapors. Ideally a separate drying room with area ventilation should be installed. Combining these ventilation needs with a properly designed spray booth (if one is used) yields a total of approximately 13,000 CFM of air, which will need to be exhausted.

In the south, with mild winters, an open garage door will be sufficient to allow replacement of the air being removed. However, in the north during winter, the open door is not practical. A heated source of replacement air must be installed to ensure a habitable workplace. This will be expensive in two ways. The initial capital cost is high and the continuing cost of heating oil or gas will be high.

A study was performed in a shop located in Syracuse, NY where the average outside air temperature from December through February is 25 F and there are approximately 7000 heating degree-days per year. The shop has an efficient spray booth exhausting 6100 CFM. The heating costs were first determined using the cost with only the spray booth ventilating as a baseline. The annual heating cost at the prevailing cost of fuel was calculated to be $2819 per year. When a properly ventilated stripping tray, water rinse booth and a drying room are added the heating cost jumps to $6829 per year.

An additional increase in operating costs was discovered during a four hour experiment performed at a shop using a methylene chloride stripper on a wash tray with integral ventilation compliant with the OSHA regulation, it was found that consumption of stripping solvent doubled over that which would be used in the normal inadequately ventilated wash tray. Obviously, this will result in a doubling of the solvent cost to strip a piece of furniture.

For those of you in the south or in the north and willing and able to pass on these operating cost increases to your customers, Seneca Research offers the Millennium Model 2000™ stripping trays.

There are other options. The shop owner who is flexible and willing to throw off the ingrained pattern of operations developed over the years can still function in an economic manner. Other stripping solvents and systems are available and Seneca Research can supply them.