1.0

PURPOSE

The purpose of this survey is to reflect the findings of a Conveyor System Noise Level survey conducted on the 17 August 2001 at PORTNET Richards Bay.

2.0

INTRODUCTION

Conveyor and Piping Systems cc produce conveyor systems utilising work rolls composed of two different material; i.e. Steel-based and Titanium-enriched Polyvinyl Chloride based.  Besides the increased strength offered by titanium, the product is resistant to Ultra-violet radiation and is anti-static.  This makes it ideal for use in environments where static charge is forbidden.  There is also speculation that the Titanium-enriched PVC should produce lower noise levels during operation as compared to the conventional Steel-based rolls.

Mr. Diethard Mathy, on behalf of Conveyor and Piping Systems cc, requested POLYTECH (PTY) LTD to conduct an investigation to compare the noise levels produced by both systems during operation at PORTNET, Richards Bay.  Subsequently, a consultant from POLYTECH (PTY) LTD visited the site during 17 August 2001, to perform the applicable noise level measurements.

3.0

HEALTH HAZARDS ASSOCIATED WITH EXPOSURE TO NOISE

Noise or unwanted sound is one of the most widely and frequently experienced problems of the industrial working environment.  It can annoy, interfere with communication, cause fatigue, and reduce work efficiency.  Of major concern, however is that intense noise or long periods in a noisy environment can cause a permanent reduction of hearing sensitivity through damage to the sensory organs of the inner ear.  This type of noise induced hearing damage or loss can seriously affect speech recognition and may be irreparable.

The risk of hearing damage escalates with increasing levels and time period of noise exposure.  It also depends on the characteristic of the offending sound, such as its frequency and whether it is impulsive or continuous.  In addition, some individuals are more susceptible to the harmful effects of noise than others.

4.0

SURVEY METHODOLOGY

The Method followed during this survey is described in SABS 083:1996.  "The Measurement and Assessment of Occupational Noise for Hearing Conservation Purposes".  The noise level was measured by means of a Quest, Type 1 (IBC spec. 651/804, Model 1800 impulse, precision integrating sound level meter, calibrated before and checked after measurements, with a Quest CA22 (IEC spec. 942) sound level calibrator. No background noise correction were made as the differnce between the measured signal and any background influences was greater than 10dB.

5.0

RESULTS

The results of the Noise Level Measurements performed at PORTNET Richards Bay on 17 August 2001 ate indicated in table 5.1

TABLE 5.1:  CONVEYOR SYSTEM NOISE MEASUREMENT RESULTS CONDUCTED AT PORTNET RICHARDS BAY, 17 AUGUST 2001

Work Roll

Type

Position/Location

(1 metre from conveyor belt)

Noise Level

dB(A)

Comments

No Load.  Measurement approximately 90m from N2 drive motor.

Titanium-enriched PVC

K24 Conveyor

75.5#

No Load. Measurement approximately 100m from Plough.  No significant additional noise sources.

Note:

dB(A)

=    Decibel,  A band frequency 

*

=    Noise level equal to or exceeding the South African statutory limit of 85dB(A) (thus excessive)

#

=    Same circumstance noise levels, for the basis of comparison