Partial cooling of the upper body with a water-cooled vest in an environment exceeding body temperature.

Objectives: To evaluate the efficacy of water-cooled clothing that continuously cools restricted body areas to suppress body temperature increase as an anti-heatstroke measure for workers in hot environments that exceed body temperature.

Methods: Ten healthy men were placed in Room A (air temperature: 25°C, relative humidity: 50%) for 15 min. They were then transferred to Room B (air temperature: 40°C, relative humidity: 50%), where they rested for 10 min, then put on cooling clothing, and again rested for 15 min (the control group rested for 25 min).

A fan-attached jacket worn in an environment exceeding body temperature suppresses an increase in core temperature.

We examined whether blowing hot air above body temperature under work clothing may suppress core temperature. Nine Japanese men engaged in two 30-min bicycle ergometer sessions at a workload of 40% VOmax at 40 °C and 50% relative humidity. The experiment was conducted without wearing any cooling apparatus (CON), wearing a cooling vest that circulated 10.

Efficacy of ice slurry and carbohydrate-electrolyte solutions for firefighters.

Objectives: To examine the thermoregulatory and fluid-electrolyte responses of firefighters ingesting ice slurry and carbohydrate-electrolyte solutions before and after firefighting operations.

Methods: Twelve volunteer firefighters put on fireproof clothing and ingested 5 g/kg of beverage in an anteroom at 25°C and 50% relative humidity (RH; pre-ingestion), and then performed 30 minutes of exercise on a cycle ergometer (at 125 W for 10 minutes and then 75 W for 20 minutes) in a room at 35℃ and 50% RH. The participants then returned to the anteroom, removed their fireproof clothing, ingested 20 g/kg of beverage (post-ingestion), and rested for 90 minutes.

Development of a method for estimating oesophageal temperature by multi-locational temperature measurement inside the external auditory canal.

We aimed to develop a practical method to estimate oesophageal temperature by measuring multi-locational auditory canal temperatures. This method can be applied to prevent heatstroke by simultaneously and continuously monitoring the core temperatures of people working under hot environments. We asked 11 healthy male volunteers to exercise, generating 80 W for 45 min in a climatic chamber set at 24, 32 and 40 °C, at 50% relative humidity.

Assessment of exposure to voices and noise via earphones in manufacturing industry workers in Japan.

Objectives: There is concern that sound via earphones and headphones attached to headsets used in workplaces may be a risk factor for noise-induced hearing loss (NIHL). Although there are some previous studies investigating exposure to noise from headphones, almost none have assessed the risks to workers who use earphones. We assessed exposure to noise among workers who regularly wear earphones in noisy workplaces.

Urinary 1-hydroxypyrene levels among office workers living in industrial areas.

We examined exposure to polycyclic aromatic hydrocarbons (PAHs) among non-smoking office workers in 2 countries living in the vicinity of a coke-oven factory by measuring their levels of urinary 1-OHP, a known metabolite of PAHs. Subjects included 10 non-smoking office workers in Kitakyushu city (Japan) and 20 workers in Thai Nguyen city (Vietnam). Measurement was optimized by using the high-performance liquid chromatography (HPLC) method developed by Jongeneelen et al.

Urinary 1-hydroxypyrene and 8-hydroxydeoxyguanosine levels among coke-oven workers for 2 consecutive days.

Objectives: This study evaluated the levels of exposure to polycyclic aromatic hydrocarbons (PAHs) and their relationship with oxidative DNA damage among Vietnamese coke-oven workers.

Methods: We collected urine from 36 coke-oven workers (exposed group) at the beginning and end of the shift on 2 consecutive days. We also collected urine from 78 medical staff (control group).

Urine temperature as an index for the core temperature of industrial workers in hot or cold environments.

Workers working in hot or cold environments are at risk for heat stroke and hypothermia. In Japan, 1718 people including 47 workers died of heat stroke in 2010 (Ministry of Health Labour and Welfare, Japan 2011). While the American Conference of Governmental Industrial Hygienists (ACGIH) recommendation lists the abnormal core temperature of workers as a criterion for halting work, no method has been established for reliably measuring core temperatures at workplaces.

Improvements in sound attenuation performance with earplugs following checklist-based self-practice.

The hearing protectors most often used in noisy workplaces are earplugs. The sound attenuation performance of earplugs depends in part on the user's skill and knowledge. This study sought to clarify whether individual training and self-practice based on a checklist can improve sound attenuation.

[Assessment of telephone operators' exposure to sound through headphones].

We estimated the level of noise that telephone operators were exposed to through headphones by a two-step method using an artificial ear technique and a manikin technique. In the artificial ear technique, the sound pressure level (Leq) of the total work hours was 81.5 dB, whereas the Leq of the total duration of phone calls was 89.

Temporary threshold shifts at 1500 and 2000 Hz induced by loud voice signals communicated through earphones in the pinball industry.

To assess the risk of hearing loss among workers using earphones as communication devices at noisy worksites, we compared temporary threshold shifts (TTS) between ears on which workers wore earphones and ears on which no earphones were worn. We measured ambient noise and personal noise exposure as well as noise generated by and passed through earphones by applying frequency analysis at three pinball facilities during their hours of actual operation. We assessed hearing levels before and after a work shift (prework and postwork) of 54 workers by pure tone audiometry at six frequencies.

[Development of a computerized sound attenuation measurement system of hearing protectors based on Japanese Industrial Standard(JIS)].

Sound attenuation measurement of hearing protectors is done in accordance with JIS T 8161 in Japan. In the JIS T 8161 it is stated that more than three non-coherent sets which include a noise generator, one-third octave band-pass filter, amplifier, calibrated attenuator and signal interrupter are required. To realize this measurement system, various expenses and a large space are required.

[Development of a hospital information system simulator for education].

When teaching students the hospital information system, it is impossible to use an actual hospital information system because of security reasons. To overcome this problem, a simulator of the hospital information system for student education has been developed. The purpose of this system is to help students understanding a hospital information system from actual experience.

Noise attenuation characteristics of a foam type earplug measured using a dummy head.

The attenuation characteristics of the earplug using a dummy head (KEMAR; Knowles Electronics Manikin for Acoustic Research) were measured, when it was exposed to pure tones or broadband noises at three different sound pressure levels (SPLs) of 70, 80 and 90 dB SPL in the 'wide frequency range from 250 to 20 k Hz. We ascertained the satisfactory capacity of noise attenuation except for from 10 k to 14 k Hz. The noise attenuation level increased with frequency until 2 k Hz, became almost constant until 8 k Hz, then decreased at around 10 k to 14 k Hz, and recovered in the range from 16 k to 20 k Hz.