LAB REPORT

Lab report

Lab Report

Introduction

Physically, there is no difference between sound and noise. Sound is a sensory perception and noise corresponds to undesired sound. By extension, noise is any unwarranted disturbance within a useful frequency band (Carpenedo & Needham, 2007: 1141). Noise is present in every human activity, and when assessing its impact on human well-being it is usually classified either as occupational noise (i.e. noise in the workplace), or as environmental noise, which includes noise in all other settings, whether at the community, residential, or domestic level.

In UK, 4-5 million people (12-15% of the workforce) are exposed to noise levels defined as hazardous by WHO (WHO, 2001). The situation is improving in developed countries, as more widespread appreciation of the hazard has led to the introduction of protective measures. Data for developing countries are scarce, but available evidence suggests that average noise levels are well above the occupational level recommended in many developed nations (Suter, 2000; WHO/FIOH, 2001). Occupational noise is a widespread risk factor, with a strong evidence base linking it to an important health outcome (hearing loss) (Christ, 2006: 78). It is also distinct from environmental noise, in that it is by definition associated with the workplace, and is therefore the responsibility of employers as well as individuals (Gupta & Mittal, 2009: 158).

Methods

Participants and Setting

Participants were enrolled at the therapeutic workplace at the Center for Learning and Health located in Leeds Metropolitan University, Maryland. The therapeutic workplace program consists of pharmacological and behavioral treatment for drug addiction and provisions of employment training. Participants had the opportunity to attend the program for approximately four hours per weekday, divided into two-hour shifts (a.m. and p.m.), and engage in computerized training and education delivered on-site. The therapeutic workplace is divided into three classrooms, and all participants in the current study worked in the same classroom. All participant computer workstations had a computer on a desk (Packard, 1970: 13). During the study, all participants worked at training programs designed to improve typing and keypad skills (Silverman, 2004; Silverman et al., 2007). The ambient sound level in the classroom was approximately 43 dB.

Procedures

Automated sound level measurement. A Smart Sensor Digital Sound Level Meter Model AR834 from Intell Instruments was used to measure sound levels. The sound meter was located in the middle of the classroom in the middle of the classroom (see Figure 1). The sound meter was connected to a personal computer, and a graphic user interface program included with the sound meter displayed sound levels in dB via text and a line graph on the computer screen.

Figure 1: sound meter was located in the middle of the classroom in the middle of the classroom

A noise violation was defined as any auditory stimulus that exceeded 55 dB, based on criteria established in (Pawlaczyk-Luszczynska, Szymczak, Dudarewicz, Sliwinska-Kowalska 2006: 185) as appropriate sound levels for activities. This definition of a noise violation differs from the Carpenedo and colleagues' (2007), definition of a library mode violation, as staff was responsible for detecting violations in ...