Disposable Nitrile Glove Resistance to Limonene: Dextrous Robot Hand Versus ASTM F739 Comparison.

The current technique to assess glove resistance to chemicals for worker protection relies on challenging a flat, 2.54 cm diameter glove piece at or near room temperature. This does not simulate a donned whole glove near the skin temperature subjected to work activity forces. Four different types of disposable nonpowdered unlined/unsupported nitrile gloves in triplicate were measured for thickness, porosity, and for the acrylonitrile content (A) of the challenge and collection sides. Limonene permeation at 35 °C through a whole glove on a clenching and nonclenching dextrous robot hand and with the standard ASTM F739 technique were facilitated by taking samples from the collection sides for GC-MS analysis. The standardized breakthrough time (SBT) when permeation reached 100 ng/cm2/min and the steady state permeation rate (SSPR) depended on A, thickness, and porosity. Only the thinnest glove (Lavender) showed statistically significant (p ≤ 0.05) increased average SSPR for the clenching hand relative to the nonclenching hand and for the ASTM technique. The ASTM test data for the three thickest gloves were not statistically different from those of the robot hand, but differed from the manufacturer's. More research with different chemicals and higher clenching forces is needed. Clenching forces can enhance the permeation. Workers wearing ultrathin disposable nitrile gloves have a higher potential for chemical penetration/permeation. Company glove permeation data obtained near room temperature may have a longer SBT and lower SSPR than in practice. Double gloving may be advisible in emergencies and for unknown chemicals when no appropriate thicker Chemical Protective glove is available.

Whole glove permeation of cyclohexanol through disposable nitrile gloves on a dextrous robot hand and comparison with the modified closed-loop ASTM F739 method 1. No fist clenching.

The aim was to develop a whole glove permeation method for cyclohexanol to generate permeation parameter data for a non-moving dextrous robot hand (normalized breakthrough time tb, standardized breakthrough time ts, steady state permeation rate Ps, and diffusion coefficient D). Four types of disposable powderless, unsupported, and unlined nitrile gloves from the same producer were investigated: Safeskin Blue and Kimtech Science Blue, Purple, and Sterling. The whole glove method developed involved a peristaltic pump for water circulation through chemically resistant Viton tubing to continually wash the inner surface of the test glove via holes in the tubing, a dextrous robot hand operated by a microprocessor, a chemically protective nitrile glove to protect the robot hand, an incubator to maintain 35°C temperature, and a hot plate to maintain 35°C at the sampling point of the circulating water. Aliquots of 1.0 mL were sampled at regular time intervals for the first 60 min followed by removal of 0.5 mL aliquots every hour to 8 hr. Quantification was by the internal standard method after gas chromatography-selective ion electron impact mass spectrometry using a non-polar capillary column. The individual glove values of tb and ts differed for the ASTM closed loop method except for Safeskin Blue, but did not for the whole glove method. Most of the kinetic parameters agreed within an order of magnitude for the two techniques. The order of most protective to least protective glove was Blue and Safeskin, then Purple followed by Sterling for the whole gloves. The analogous order for the modified F739 ASTM closed loop method was: Safeskin, Blue, Purple, and Sterling, almost the same as for the whole glove. The Sterling glove was "not recommended" from the modified ASTM data, and was "poor" from the whole glove data.

Whole glove permeation of cyclohexanol through disposable nitrile gloves on a dextrous robot hand: Fist clenching vs. non-clenching.

The differences in permeation parameters when a gloved dextrous robot hand clenched and did not were investigated with the dynamic permeation system described in the companion paper. Increased permeation through the gloves of the present study for cyclohexanol when the gloved hand clenched depended on glove thickness and porosity for cyclohexanol permeation. The Sterling glove, the thinnest and most porous, was the least protective. Hand clenching promoted more permeation for the Sterling glove in terms of breakthrough times, steady state permeation rate, and diffusion coefficient. The Safeskin glove showed increased permeation only for the steady state permeation rate but not breakthrough times or diffusion coefficient. The Blue and Purple gloves showed no differences when the hand was clenching or not. The correlational analysis supported differences between the clenching and non-clenching situations, and the risk assessment considered the worst and best scenarios relative to one and two hydrated hands that were and were not protected by specific gloves.