A Methods Manual for the Collection, Preparation and Analysis of ...

SECTION 3: LABORATORY PROCEDURESTo facilitate the reading of this document references have been kept to a minimum. Howeverit should be mentioned that the methods described below have been based on several keydocuments including: Kelly et al. (1998), CEN (2004), DARES (2004) and Taylor et al.(2005).Health and safety of laboratory staff (general comments)The specific health and safety risks involved in each of the diatom preparationmethods will be dealt with below. However, several general rules apply for safelaboratory practice: Always work in a well ventilated room. If a reaction or procedure results in the production of vapors, fumes or smokeALWAYS work in a fume cabinet. Proper care and attention should be paid to the storage and handling ofdangerous chemicals. Do NOT dispose of hazardous chemicals or any other chemical compounds intothe municipal sewage system. Avoid the use of dangerous chemicals if other less dangerous chemicals may besubstituted. Work areas in the laboratory should be adequately delineated and carry theappropriate warning and advisory signs1. Preparation1.1 ToolkitBeakers (easy to clean) - (50, 100, 250 ml)Watch glasses to cover beakers (prevent cross-contamination between samples)Test tubesPasteur pipettes (a cheap alternative is drinking straws)/Micro- Pipette with disposabletipsHot Plate for heating diatom material (inside a fume cabinet)Vortex mixer (optional)Separate hot-plate/slide dying bench for curing slides (inside a fume cabinet)Reagents (clearly marked and correctly stored)Waste bottles for disposal of hazardous compounds.26