How do logos and certification help consumers to buy standardized products? Suggest two other ways by which consumers can be protected?

Logos and certifications on a product suggests that it meets the standards of national or international standardisation institutions. Like the ISI,AGMARK etc show that the product the consumer buys, is of the rising standard it should meet. Other than these, there are more ways consumers can be protected like creating awareness among people to make them become better consumers and the acts passed down by the government like the RTI, COPRA etc also help consumers to protect themselves from unjust practices of the market.