Risk assessment COSHH risk assessment - University of Oxford COSHH Assessment Form Description of procedure Determination of bacterial antimicrobial susceptibilities by disk diffusion Substances used 1. Cultured bacteria 2. Antimicrobial impregnated disks Quantities of chemicals used 5ml of bacterial suspensions Frequency of SOP use Hazards identified 1. Autoclaved liquid 2. Potentially infectious material in sample Potentially pathogenic bacteria Could a less hazardous substance be used instead? No What measures have you to control risk? 1. Training in good laboratory practices (GLP) 2. Appropriate PPE (lab coat, gloves, eye protection) 3. Use of biosafety cabinet for reading of plates / follow-up of BSL-3 organisms (e.g. B. pseudomallei) Checks on control measures Observation and supervision by senior staff Is health surveillance required? No Training requirements 1. GLP 2. Specific training in this SOP Emergency procedures 1. Report all incidents to Safety Adviser 2. Use eyewash for splashes 3. Clean up spills using 1% Virkon or chemical spill kit Waste disposal procedures 1. Sharps discarded into appropriate rigid containers for incineration 2. Infectious waste discarded into autoclave bags or 1% Virkon solution prior to autoclaving and subsequent incineration 3. Chemical waste disposed of according to manufacturer’s instructions
Appendix 1: Antimicrobial disk testing panels and interpretations Staphylococcus spp. Drug Details Zone (mm) / MIC (µg/ml) Comment Code µg S I R Plate 1 Cefoxitin Report as oxacillin S. aureus FOX 30 ≥22 - ≤21 CoNS FOX 30 ≥25 - ≤24 Ciprofloxacin CIP 5 ≥21 16-20 ≤15 Erythromycin E 15 ≥23 14-22 ≤13 Gentamicin CN 10 ≥15 13-14 ≤12 Penicillin P 10 ≥29 - ≤28 Co-trimoxazole SXT 25 ≥16 11-15 ≤10 Plate 2 Only set up if ≥3 drugs on plate 1 are resistant (or if cefoxitin resistant) Drug Details Zone (mm) / MIC (µg/ml) Comment Code µg S I R Chloramphenicol C 30 ≥18 13-17 ≤12 Clindamycin DA 2 ≥21 15-20 ≤14 Rifampicin RD 5 ≥20 17-19 ≤16 Do not report Tetracycline TE 30 ≥19 15-18 ≤14 Do not report Vancomycin
S. aureus VA 30 ≥7 - - VA Etest ≤2 4-8 ≥16 CoNS VA Etest ≤4 8-16 ≥32 Streptococcus pneumoniae Drug Details Zone diameter (mm) Comment Code µg S I R Plate 1 Chloramphenicol C 30 ≥21 - ≤20 Clindamycin DA 2 ≥19 16-18 ≤15 Do not report Erythromycin E 15 ≥21 16-20 ≤15 Oxacillin OX 1 ≥20 - - See below Co-trimoxazole SXT 25 ≥19 16-18 ≤15 Tetracycline TE 30 ≥28 25-27 ≤24 Do not report Plate 2 Only set up PG and TX Etests if oxacillin zone <20mm (can put both on same agar plate) Drug Details MIC (µg/ml) Comment Code µg S I R Ceftriaxone Meningitis TX Etest ≤0.5 1 ≥2 Non-meningitis TX ≤1 2 ≥4 Penicillin Meningitis PG ≤0.06 - ≥0.12 Non-meningitis PG Etest ≤2 4 ≥8
Alpha- and Beta-haemolytic streptococci Drug Details Zone (mm) / MIC (µg/ml) Comment Code µg S I R Ceftriaxone CRO 30 ≥27 25-26 ≤24 Beta-haem CRO 30 ≥24 - - Chloramphenicol C 30 ≥21 18-20 ≤17 Clindamycin DA 2 ≥19 16-18 ≤15 Do not report Erythromycin E 15 ≥ 21 16-20 ≤15 Penicillin Only do PG Etest if significant blood culture isolate PG Etest ≤0.12 0.25-2 ≥4 Beta-haem P 10 ≥24 - - Enterococcus spp. Drug Details Zone diameter (mm) Comment Code µg S I R Ampicillin AMP 10 ≥17 - ≤16 Chloramphenicol C 30 ≥18 13-17 ≤12 Ciprofloxacin CIP 5 ≥21 16-20 ≤15 Vancomycin VA 30 ≥17 15-16 ≤14
Enterobacteriaceae (coliforms) Drug Details Zone diameter (mm) Comment Code µg S I R Plate 1 Ampicillin AMP 10 ≥17 14-16 ≤13 Cefpodoxime* CPD 10 ≥21 18-20 ≤17 Do not report Ciprofloxacin CIP 5 ≥21 16-20 ≤15 Gentamicin CN 10 ≥15 13-14 ≤12 Co-trimoxazole SXT 25 ≥16 11-15 ≤10 Imipenem IPM 10 ≥23 20-22 ≤19 2 Set up on all isolates Drug Details Zone diameter (mm) Comment Code µg S I R Co-amoxiclav AMC 30 ≥18 14-17 ≤13 Ceftazidime* CAZ 30 ≥21 18-20 ≤17 Do not report Ceftriaxone* CRO 30 ≥23 20-22 ≤19 Chloramphenicol C 30 ≥18 13-17 ≤12 Do not report if Nitrofurantoin F 300 ≥17 15-16 ≤14 *Do ESBL tests on the following organisms: E. coli and Klebsiella spp. that have cefpodoxime ≤ 17 mm OR ceftriaxone zones ≤ 25 mm OR
Shigella spp. Drug Details Zone diameter (mm) Comment Code µg S I R Ciprofloxacin CIP 5 ≥21 16-20 ≤15 Acinetobacter spp. Drug Details Zone diameter (mm) Comment Code µg S I R Ceftazidime CAZ 30 ≥18 15-17 ≤14 Ceftriaxone CRO 30 ≥21 14-20 ≤13 Ciprofloxacin CIP 5 ≥21 16-20 ≤15 Co-trimoxazole SXT 25 ≥16 11-15 ≤10 Gentamicin CN 10 ≥15 13-14 ≤12 Imipenem IPM 10 ≥16 14-15 ≤13 Burkholderia cepacia Drug Details Zone diameter (mm) Comment Code µg S I R Ceftazidime CAZ 30 ≥21 18-20 ≤17 Co-trimoxazole SXT 25 ≥16 11-15 ≤10 Burkholderia pseudomallei
Co-trimoxazole SXT 25 ≥13 11-12 ≤10 Neisseria meningitidis Drug Details Zone (mm) / MIC (µg/ml) Comment Code µg S I R Ceftriaxone CRO 30 ≥34 - - Chloramphenicol C 30 ≥26 20-25 ≤19 Ciprofloxacin CIP 5 ≥35 33-34 ≤32 Penicillin PG ≤0.06 0.12-0.25 ≥0.5 Neisseria gonorrhoeae Drug Details Zone diameter (mm) Comment Code µg S I R Ciprofloxacin CIP 5 ≥41 28-40 ≤27 Ceftriaxone CRO 30 ≥35 - - Penicillin P 10 ≥47 27-46 ≤26 Tetracycline TE 30 ≥38 31-37 ≤30 Do not report Appendix 2: Antimicrobial disk QC templates
SXT 25 - - 23-29 24-32 - - TE 30 - - - - 24-30 - - VA 30 - - - - 17-21 - - ESBL disk / Mueller-Hinton agar (MH) QC sheet QC strain: E. coli ATCC 25922; K. pneumoniae ATCC 700603 Date MH prepared: Date zones measured: QC performed by: Disk details Zone diameter (mm) Zone diameter (mm) E. coli ATCC K. pneumoniae ATCC 700603 Code µg Expected Measured Expected Measured CAZ 30 25-32 10-18 CAZ/CLAV 30/10 2mm increase from CAZ alone ≥ 5mm increase from CAZ alone CPD 30 Not defined by CLSI* Not defined by CLSI* CPD/CLAV 30/10 Not defined by CLSI* Not defined by CLSI* CTX 30 29-35 17-25 CTX/CLAV 30/10 2mm increase from CTX alone ≥ 3mm increase from CTX *CLSI protocol uses CPD10 disk