Carpets, formaldehyde release rate

Unwashed new clothing samples (Table IIC), fiberglass insulation products with formaldehyde resins (Table IID), paper products (Table HE), fabrics (cotton, nylon, olefin, and blended) (Table HF), and carpets (Table HG), had substantially 3 to > 100 fold) lower formaldehyde release rate coefficients, as measured by this method, than did pressed wood products or urea formaldehyde foams (1, 15). 

Formaldehyde release rates were measured using multiple consumer products in a dynamic chamber. Particle board and plywood had high formaldehyde specific release rate coefficients. Combined plywood and particle board had a release rate 68% of the sum of the two products and 91% of the particle board release (Table V). When particle board was combined with insulation, the combined release rate was 71% of the sum of the separate release rates and 73% of the particle board release. Particle board and carpet combinations gave similar results. 

A new office building has synthetic carpet laid in all its offices. Formaldehyde (HCHO) is released from the carpet at a rate of approximately 10 /xg/hr in an office, and one worker in this 72 ft2 office with an 8-ft ceiling complains of feeling nauseous from the chemical. Ambient air concentration of formaldehyde is 5 ppb. What ventilation rate is needed in this office to decrease the formaldehyde concentration to 0.1 ppb, assuming a density of air at room temperature of approximately 1.2 kg/m3 ... 

Formaldehyde (CH2O) release was measured for seven types of consumer products pressed wood, urea formaldehyde foam materials, clothes, insulation, paper, fabric, and carpet. A modified Japanese Industrial Standard (JIS) desiccator test was used to measure release rate coefficients and to rank 53 products. Ten pressed wood products and five urea formaldehyde foam products showed the highest CH2O releases (1-34 mg m 2.day"b The remainder, representing all product types, had lower releases ranging from 680 yg m 2.day to nondetectable levels. In other studies, CH2O release was measured in a ventilated chamber for single samples of particle board, plywood, insulation, and carpet. 

A good correlation was noted between release rate coefficients at loadings of 1.4-2.8 m2 of product surface area/m of chamber volume and formaldehyde extractable into toluene (Table V r = 0.999 p = < 0.001). Total extractable formaldehyde was quite low in both carpet and fiberglass insulation (0.5-1.6 mg/100 g of material) relative to that in plywood or particle board (22-55 mg/100 g of material) (Table V) (12). 

The relative ranking for each type of product on the basis of rate of release of formaldehyde per unit surface area was pressed wood products z formaldehyde foam clothes z insulation products z paper products > fabric > carpet. Considering the surface area of each type of product likely to be present in houses and the relative release rate coefficients. 

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