DPD-based colorimetric quantification of free available chlorine (FAC) in floatation tank conditions
Notice bibliographique
Résumé

 Background: Floatation tanks are quickly gaining traction as a form of relaxation, with numerous spas emerging in the Lower Mainland and beyond. The tanks are filled with a solution of magnesium sulphate, recycled between client uses. Thus, there exists a potential for microbiological contamination and subsequently, disease transmission. Health inspectors in BC may be involved the approval and inspection process for floatation tank spas; therefore, it is important to ensure that floatation tank environments are not a vehicle for disease. As a preventative measure, guidelines are in place for the halogenation of tank water at a level of 3-5 ppm free available chlorine (FAC). However, there is no standard method for the accurate and reliable quantification of FAC in high salinity environments. This study characterized the effect of high salinity on FAC readings from the HACH Pocket Colorimeter™, and derived a conversion factor to obtain an accurate reading for inspectors in the field. Methods: Floatation tank environments were simulated using USP-grade Epsom salts, Clorox™ bleach, and a hot water bath set at approximately 34°C (93°F). Assuming an initial concentration of 5.25% sodium hypochlorite, the bleach was serially diluted to obtain concentrations from 1-8 ppm. The final dilution step involved the addition of either 34°C water or an Epsom salt solution (MgSO4) at a specific density of 1.220 to create two solutions with identical amounts of bleach - one with and one without salt. The solutions were tested for chlorine two minutes later through the addition of DPD - a colorimetric dye that results with FAC - and measuring the colour intensity using the Pocket Colorimeter II. A percentage recovery was derived using the ratio between measured FAC with and without salt, Results: There was a statistically significant difference (p=0.05) between measured chlorine levels with and without salt as determined by a paired t-test. Further analysis via ANOVA and a post-hoc multiple comparison test (Scheffe's) indicated a dose-response relationship - increasing the amount of hypochlorite in an Epsom solution results in a statistically significant increase in measured FAC between the following groups: 1-2 ppm, 3-5 ppm, and 6-8 ppm of added hypochlorite. Linear regression revealed a strong correlation (0.97) between measured chlorine with and without salt. Conclusions: The HACH Pocket Colorimeter II™ can be used to estimate the amount of FAC in a floatation tank solution using a conversion factor of 0.79; to obtain an accurate measurement, divide the FAC reading in salt by 0.79
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,002 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,001 | 0,000 |
| Communication savante | 0,000 | 0,001 |
| Science ouverte | 0,001 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,009 | 0,001 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».