bids are invited for calcium carbonate 20g crm in accordance with iso 17034 certificate. , fluoride standard solution– 1000 ppm, 500ml crm in accordance with iso 17034 certificate , sodium chloride 45g crm in accordance with iso 17034 certificate , sodium carbonate 45g crm in accordance with iso 17034 certificate , potassium dichromate 45g crm in accordance with iso 17034 certificate , buffer solution ph 4 - 500ml crm in accordance with iso 17034 certificate , buffer solution ph 7 - 500ml crm in accordance with iso 17034 certificate , buffer solution ph 10 - 500ml crm in accordance with iso 17034 certificate , turbidity standard solution 1000ntu– 500ml. crm in accordance with iso 17034 certificate , potassium hydrogen phthalate 45g crm in accordance with iso 17034 certificate , boron standard solution 1000ppm-100ml. crm in accordance with iso 17034 certificate , nitrite standard solution 1000ppm- 500ml. crm in accordance with iso 17034 certificate , silicon standard solution 1000ppm-500ml. crm in accordance with iso 17034 certificate , phosphate standard solution 1000ppm-100ml crm in accordance with iso 17034 certificate , potassium hydrogen diiodate standard– 1000 ml crm in accordance with iso 17034 certificate , bod standard solution– 500ml crm in accordance with iso 17034 certificate , ammonium standard solution 1000ppm– 100 ml crm in accordance with iso 17034 certificate , ammonia ph adjusting isa– 475ml(951211)